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Market and Underground Activities in a Two-Sector Dynamic Equilibrium Model∗ Francesco Busato† Columbia University Bruno Chiarini University of Naples This version: May 24, 2002 Abstract In this paper a two sector dynamic general equilibrium model is developed in order to evaluate the implications of the underground economy from a business cycle perspective. There are three main results. First, introducing an underground sector improves the fit of the model to the data, especially along several important labor market dimensions. Second, the model produces substantial internal propagation of temporary shocks. Third, it is shown that underground activities offer risk sharing opportunities by allowing households to smooth income through a proper labor allocation between the two sectors. Journal of Economic Literature Classification Numbers: E320, E260, J22, H200. Keywords: Two-sector Dynamic General Equilibrium Model, Underground Economy, Propagation of Shocks, Taxation. ∗ We have benefited from the comments and suggestions of John Donaldson. We thank also Paolo Siconolfi, Edmund Phelps, Domenico Tosato and the participants in the seminars at various Universities. We also thank David Giles and Stefano Pisani for providing useful information on the underground data, Francesca Caponi for the comments and the information concerning the legal and fiscal aspects involved in the calibration, and Glenn Williams for the research assistance. Chiarini acknowledges financial support from the Ateneo Research fund of the University of Rome, La Sapienza, Dinamiche dell’integrazione europea e scelta di politica economica. All errors are ours. † Department of Economics, Columbia University, Mail Code 3308, 420 W 118th st, New York, NY 10027. E-mail: [email protected]. Fax number: +1-212- 854-8059 or +39-06-86216758. 1 Introduction In this paper we present a dynamic general equilibrium model that includes an explicit modelling of the ”underground economy”. Shadow, non-market or underground activities are a fact in many countries, and there are significant indications that this phenomenon is large and increasing.1 The estimated average size of underground sector (as a percentage of total GDP) over 1996-97 in developing countries is 39 percent, on transition countries 23 percent, and in OECD countries about 17 percent.2 Table 1, drawn from a recent survey by Schneider and Enste (2000), shows that the size of underground economic activity is quite large and increasing in many European countries. Table 1 Even though the precise definition of the phenomenon often varies depending on the chosen method of measurement, it is worth noticing that different measurement techniques provide similar approximate magnitudes of the size and development of the underground economy across countries.3 Since these unreported activities make a sizeable contribution to national production and income, we will argue that it is difficult to understand the business cycles without some knowledge of the fluctuations of this relevant component of the aggregate economy. In fact, 1 There is no universal agreement on what defines the underground economy. Most recent studies use one of more of the following definitions: (a) unrecorded economy (failing to fully or properly record economic activity, such as hiring workers off-the-book); (b) unreported economy (legal activity meant to evade the tax code); (c) illegal economy (trading in illegal goods and services). Obviously, the difficulty in defining the sector extends to the estimation of its size. We are concerned with the size of the underground economy as encompassing those activities which are otherwise legal but go unreported or unrecorded. 2 Note that there exist several synonyms for describing what underground activities are: underground or non-market activities, shadow or hidden economy. On the other hand we denote official activities as the official sector, or as market activities. 3 There exist several methods of estimating the size of the underground economy. A detailed survey of the most widely methods used to measure the hidden activity are discussed in Schneider and Enste 2000. See also Feige (1989) and Thomas (1992; 1999) among others. 1 what is most interesting from the business cycle perspective is that the estimated data reveals that the non-market produced GDP presents cyclical features significantly different from those of the market sector. Figure 1 encapsulates the graphs of the Hodrick-Prescott filtered series for the market and the underground components of GDP for Italy, New Zealand, the United States and the United Kingdom. A casual glance at these graphs suggests that official and underground activities give rise to two distinct cycles. This stylized fact seems peculiar to underground activities, and robust across counties: although the figures are based on different data sets and different estimation methods, they all emphasize the countercyclical nature of underground production. Figure 1 This is an interesting and striking feature suggesting that standard models omit important aspects of the real world. For example, in models with underground sectors, firms and consumers may be more willing to shift resources out of market activity in response to productivity and policy disturbances than in models without such sector. Intuitively, in an underground model, although these shocks may not affect total hours worked, they may affect how hours are allocated between the market and underground sectors. Institutional features, furthermore, can have significant effects: the structure of the parameters that drive the agent’s willingness to shift resources between sectors, such as the burden of tax and social security contributions, is relevant for determining aggregate fluctuations. In this model, firms and households, like their real world counterparts, are affected by work and revenue incentives, and undertake intra-temporal allocations of their resources in addition to intertemporal substitutions. Augmenting the standard stochastic growth model with this sector, can therefore go quite far in accounting for aggregate fluctuations in countries with reasonably sized non-market activities. In this paper we aim to replicate these features, and to show that this model formulation provides a new degree of freedom for enriching 2 the analysis of important macroeconomic phenomena, thereby producing a better understanding of business cycle dynamics, as well as presenting important policy implications. While this analysis is mostly directed to European countries like Belgium, Portugal, Spain, Greece and Denmark, as Table 1 confirms, we specifically seek to match the Italian stylized facts, because Italy present a larger underground sector, and it allows to better appreciate its impact on the economy. We focus on three major issues. First, we review some basic business cycle facts for the Italian economy and show how the introduction of an underground sector into a dynamic general equilibrium model can not only account for these facts, but also resolve some heretofore unsatisfactory results such as the employment volatility puzzle and productivity puzzle generated by standard Real Business Cycle (RBC) models.4 Second, we show how this model, augmented to include this second sector, improves the internal propagation of stochastic disturbances. Third, we assess the implication sectoral and aggregate shocks in terms of resource reallocation between the market and the underground sector. We show how underground activities help to mitigate recessions and the cost of high tax burden by allowing the household to smooth consumption through a proper labor allocation between the two sectors.5 The paper is structured as follows: Section 2 presents the structure of the model, and characterize the equilibrium for this economy, while Section 3 compare our model with home production class of models. Then Section 4 discusses calibration, and Section 5 present numerical simulation results, together with impulse response functions analysis. Section 6 offers concluding comments. 4 Although previous papers (e.g. Baxter and King, 1993 and Braun, 1994) have shown that including distortionary taxation improves the ability of the standard RBC models to match some key observations, the economic mechanism and the driving forces in a model with underground economy turn out to be quite different. 5 These results imply that the Real Business Cycle contributions that include only tax disturbances may lead to misleading predictions when underground activities are neglected. 3 2 Structure of the Model. There are three agents in the model: the firm, the consumer-workerinvestor, and the government. In addition there are two sectors: the market and the underground sector. Finally, there is a homogenous consumption good. Each firm produces final output by using two different technologies, one associated with the market, and the other with the non-market sector. We could imagine that the same firm produces in the market economy in the day, while in the underground economy by night. Following Prescott and Mehra (1980), we assume that each firm solves a myopic profit maximization problem, on a period-by-period basis, subject to a technological constraint, and to the possibility that it may be discovered producing in the unofficial economy, convicted of tax evasion and subject to a penalty surcharge. The consumers choose consumption, investment, and hours to work at each date and in each sector (official and unofficial) to maximize the expected discounted value of utility, subject to a sequence of budget constraints, a proportional tax rate on the market wage, and the law of motion for capital stock. Finally, government levies proportional taxes on revenues and incomes, and balances its budget at each point in time. We assume that government expenditure on goods and services does not contribute to either production or to household utility. 2.1 The Firms. Suppose there exists a continuum of firms, uniformly distributed over a unit interval. Each firm i ∈ [0, 1] produces a homogenous good with two different technologies, one used in market sector, and the other i , used in underground sector. Denote market-produced output as ymt i , and define total production equal non-market-produced output as yut 4 i + yi = yi 6 to ymt ut tot,t . Technologies are specified as follows: ¡ ¢α ¡ i ¢1−α i = Mt kti ymt nmt and i yut = Zt niut . (1) i , is the result of capital, k i , and market labor, The market output, ymt t nimt , applied to a Cobb-Douglas technology. The non-market output, i , is produced with a production function which uses only non-market yut labor, niut . Finally, Mt and Zt denote sectoral stochastic productivity shocks.7 Remark 1 This technology specification is equivalent to a more general set-up where both production functions use capital and labor, for ¡ ¢ ¡ ¢1−α ¡ ¢ ¡ ¢ i = M k i α ni i = Z k i β ni 1−β . From and yut example ymt t t t mt ut ut Uzawa (1965) and Lucas (1988) if β < α we can set the smaller elasticity to zero without loss of any generality. Since underground activities are labor intensive, we can simplify the model, and preserving the main economic intuition, by assuming that underground sector produces using only labor. We anticipate that in a Rational Expectations Equilibrium (REE) firms use both technologies (this claim is formally proved below). We next assume that each firm allocates a share, θti , of the total labor demand, nit , to market production (therefore nimt = θti nit ) and ¢ ¡ the remainder, 1 − θti , to the other sector (and niut = 1 − θti nit ).8 Normalizing Nti to unity, we rewrite (1) as ¡ ¢α ¡ i ¢1−α i θt ymt = Mt kti and ¡ ¢ i yut = Zt 1 − θti . (2) 6 To further clarify the notation, the subscripts m and u refer to the sector from which production originates. 7 Section (5 presents some possible interpretations for a shock on the underground sector productivity. 8 The use of a share for labor is also consistent both with the fact that labor supply per person is approximately stationary in many economies although the real wage grows, and with the utility function, homogenous in consumption, that we adopt to model the household preferences. The aim is, therefore, to analyze the movement of resources between the two sectors, to understand how agents reallocate inputs out of the market and into the underground sectors. 5 It will turn out that the reallocation of hours from market to informal sector rather than exclusively from leisure to labor, increases the volatility of the official labor input for a given technology shock. Lemma 1 characterizes the properties of the aggregate production technology. Lemma 1 (Production Technology) Production function is well behaved. Proof. Appendix A 2.1.1 Firms’ Revenues i , are taxed at the stochastic Market-produced revenues, qtm (1 − tt )ymt corporate rate tt , where qtm denotes the price of market-produced good. The process for tt is specified below, in Section 3.1.4. Firms do not pay i , where q u is the price of taxes on non-market produces revenues, qtu yut t non-market-produced commodity. Firms, however, may be discovered evading, with probability p ∈ (0, 1), and forced to pay the stochastic tax rate, tt , increased by a surcharge factor, s > 1, applied to the standard tax rate. Note that since the market-produced and the nonmarket produced goods are identical, in a REE they must have the same price. Lemma 2 proves formally this claim. Lemma 2 (Price Vector) Denote a price vector for this economy as hqtm , qtu , wt , rt i, where wt denotes labor wage, and rt is price of capital (see below). In a REE we have qtm = qtu ≡ qt . Normalizing commodity price qt to unity, the normalized price vector supporting the equilibrium equals h1, wt∗ , rt∗ i, where wt∗ and rt∗ denote equilibrium prices. Proof. Appendix A Since qt = 1 holds in the equilibrium, we can impose it along the solution. In the first case (firm is discovered,with probability p), revi , are: enues, denoted as yD,t i i i yD,t = (1 − tt )ymt + (1 − stt )yut 6 In the second case (firm is not discovered, with probability 1 − p), revenues equal: i i i yN D,t = (1 − tt )ymt + yut To compute total expected revenues, we apply linear projection, ¢ ¡ i i + (1 − p) yN and we have E yti |It = pyD,t D,t . Simplifying, we finally ¡ i ¢ i i have E yt |It = (1 − tt )ymt + (1 − pstt )yut . 2.1.2 Firms’ Costs The cost of renting capital equals its marginal productivity rt , net of capital depreciation, δ. The cost of market labor is represented by the wage paid for hours worked, augmented by social security stochastic tax rate, tt , which, for simplicity, is assumed equal to social security tax rate.9 We denote the former as wtm = (1+tt )wt , where wt is pre-tax wage, while the cost of non-market labor equals the pre-tax wage, i.e. wtu = wt . Total costs for i − th firm are defined as follows: ¡ ¢ CO θti , kti = (1 + tt )wt θti + wt (1 − θti ) + rt kti . (3) The structure of costs is consistent with the nature of underground activities. Even though it may be feasible, it would be highly unusual to see people working full time in the non-market sector. It is customary that employees work a certain amount of hours under a regular contract (for example, during the day) , while additional hours and extra-hours are done without any formal agreement (for example, by night) . From a firm’s perspective, it means that a worker’s cost is augmented by social security contributions only for the regular working time, while there is no tax wedge on his remaining hidden hours. k 9 Note that this assumption is not strong. Social Security tax rate ranges from 21% to 22%, while Corporate tax rate from 19% to 36%. Even though a complete representation of tax system would require to define a third tax rate for Social Security Contributions, we are convinced that the tax structure we are using is enough rich, and it seems to be a good approximation to actual data. 7 2.1.3 Profit Maximization At each date t, firm i maximizes period expected profits10 ¡ ¢ ¡ ¢ max E yti |It − CO θti , kti , (θti ,kti )≥0 and its behavior is characterized by the following first order necessary and sufficient conditions:11 ¡ ¢α−1 ¡ i ¢1−α θt 0 = (1 − tt )Mt α kti − rt ¡ i ¢α ¡ i ¢−α − (1 − tt ps)Zt − wt tt . 0 = (1 − tt )Mt (1 − α) kt θt 2.1.4 (4) (5) Productivity and Tax Disturbances. Finally, we formalize productivity disturbances and tax rates as a stochastic vector of variables that follow a univariate AR(1) processes in log: At+1 = ΩAt +²t where At is a vector [ln Mt , ln Zt , ln tt , ln τt ]0 containing the productivity shocks, ln Mt , ln Zt , the stochastic corporate tax rate, ln tt , and the stochastic personal income tax rate ln τt . Ω =diag (ρi ) , where i = m, z, t, τ, is a 4 × 4 matrix describing the autoregressive components of the disturbances relative to each of the four shocks. The innovation, ²0t = [εm , εz , εt , ετ ] , is a vector of i.i.d. normal random variables. 10 Note that in this context firms solve a myopic optimization problem. Given the nature of the model, it would be interesting to generalize the firms’ behavior incorporating an inter-temporal optimization problem as in Danthine and Donaldson (2001), for example. 11 i i To derive (4) and (5) compute period expected profits, pyD,t + (1 − p) yN D,t = i i i i p((1 − tt )ymt + (1 − stt )yut ) + (1 − p)((1 − tt )ymt + yut ), and then take derivatives with respect θti and kti . 8 2.2 The Consumer-Worker-Investor. Suppose there exist a continuum of consumers, uniformly distributed over a unit interval, supplying labor to the market and the underground sectors.12 Consumer j ∈ [0, 1] has preference over sequences of consumption and labor, and maximizes expected utility as summa∞ P β t u(cjt , θtj ), where Et rized by the lifetime utility function U0j = E0 t=0 is the mathematical expectations operator conditional on information available at time t, and β is a subjective discount factor. To represent consumer behavior in this environment, we take a cue from Cho and Rogerson’s (1988) and Cho and Cooley (1994) family labor supply model. They distinguish labor supply with regard to an intensive (the hours worked), and an extensive margin (the employment margin). In our model we reinterpret these two dimensions as representing worker’s labor supply in the regular and in the underground sectors. Hence we specify the momentary utility function as follows: u(cjt , θtj ) = (θj )1+γ (cjt )1−q − 1 (1 − θtj )1−η −h t (1 − θtj ) − f , 1−q 1+γ 1−η (6) where cjt denotes consumption profile of consumer j, θtj her market labor supply, and 1 − θtj her non-market labor supply. This function is separable between consumption and labor and allows to study how an household allocates its labor between the market and the underground sectors.13 To have a well behaved utility function, we assume that 12 We imagine that the same employee works some hours under a regular labor contract, and, in addition, some others under a private agreement with the employer. This working time represents consumer’s underground labor supply. 13 This specification is adapted from Cho and Rogerson (1988) and Cho and Cooley (1994). Unlike the extreme cases of indivisible labor, where all the fluctuations occur on the extensive margin, and the divisible labor in which the fluctuations take place on the intensive margin, in this formulation of preferences households may allocate their time along both margins (intensive-hours and extensive-employment margin). Cho and Rogerson achieve this feature by introducing heterogeneity into the opportunity sets of household decision makers, and Cho and Cooley introduce some fixed costs of going to work that are not explicitly modelled. This allow us to capture changes in labor in both the market and the underground sector 9 h, f ≥ 0, γ > −1, η ∈ (0, 1) and that all the parts of the momentary utility function are twice differentiable and well behaved.14 The second (θtj )1+γ j 1+γ (1−θt ), represents the overall disutility of working, while (1−θtj )1−η last term, f 1−η , reflects the idiosyncratic cost of working in term, h the the underground sector. In particular, this cost may be associated with the lack of any social and health insurance in the underground sector. The representative household faces the following budget constraint:15 wt (1 − θtj τt ) + rt ktj = cjt + xjt . (7) where xt denotes investment at time t . Finally, investment increases the capital stock according to the following state equation: j kt+1 = (1 − δ)ktj + xjt (8) where δ denotes the depreciation rate. With the period utility function defined as in equation (6) the value function Jt (ktj , Kt , At ) of the representative agent satisfies: Jt (ktj , Kt , At ) = max j kt+1 ,θtj h n io j , Kt+1 , At+1 ) | It u(cjt , θtj ) + βE Jt+1 (kt+1 subject to budget constraint (7), and the law of motion for the household capital stock (8). Lemma 3 (Existence and Uniqueness of the Policy Function) simultaneously, and it is consistent with the data, where we observe substantial variations in both the markets. 14 To have a well defined dynamic optimization problem, we want the objective function to obey well know conditions (see Stokey and Lucas, 1989). More precisely, we want that (i) the household discount factor (β) ∈ (0, 1), that the objective function is (ii) continuous and (iii) strictly increasing. Note that in this model the third requirements is not as trivial as it could seem. Condition (iii) might not hold for some parameterizations of the model. For this reason, Lemma 3 in Appendix A shows that for the parameterization presented in section 4 condition (iii) holds. 15 More precisely, the right hand side summarizes the expenditure, and it is fairly standard. The left hand side represents the income and equals wt (1 − τt )θtj + wt (1 − θtj ) + Rt ktj . To derive (7), we factorize out wt and we simplify. 10 The policy function for this problem exists, and it is unique. Proof. Appendix A After deriving and manipulating the necessary and sufficient first order conditions, we obtain the Euler equation (9), and the intratemporal consumption-labor allocation, condition (10): 1 = βE(( cjt+1 cjt )−q Rt+1 | It ) 0 = −wt τt (cjt )−q − (θtj )γ + h (9) 2 + γ j 1+γ − f (1 − θtj )−η (10) (θ ) 1+γ t ¡ i ¢α−1 ¡ i ¢1−α where (1+(1−tt+1 )Mt+1 α Kt+1 θt+1 −δ) = (1 + rt+1 − δ) ≡ Rt+1 from firm profit maximization (see section 2.1.3). 2.3 The Government. Finally, the flow government budget constraint is: wt τt θt + (pstt ) yut + tt ymt = Gt (11) where Gt = Ḡ.16 2.4 Equilibrium Equilibrium for our model is described as a Variant on a Recursive Competitive Equilibrium (RCE) of Prescott and Mehra (1980) notion. Since we are not aware of other dynamic general equilibrium models explicitly incorporating an underground sector, we describe the equilibrium in its details. A RCE for the decentralized economy with underground sector consists of: 16 Notice that the Government balances its budget only in expectation, since with probability 1 − p some firms and workers are evading. Hence equation (11) will not be satisfied on a state by state basis. 11 + 1. a set of continuous price functions, w(At , kt , Kt ) : <+ 2 7−→ < , and + + r(At , kt , Kt ) : <2 7−→ < ; + 2. a value function Jt (At , kt , Kt ) : <+ 3 7−→ < ; 3. and policy functions cj (At , kt , Kt ), θj (At , kt , Kt ), and xj (At , kt , Kt ) + all from <+ 3 7−→ < such that: 1. firms are maximizing profits at the prevailing prices, i.e. (4) and (5) are satisfied; 2. cj (kt , Kt , λt ) , θj (kt , Kt , λt ) solve (9) and (10), i.e. consumer-workerinvestors are maximizing utility at the prevailing prices; 3. government balances its budget in expectation, i.e. equation (11) holds on a period by period base; 4. market clearing conditions hold for each market. Specifically, R R for labor service in market sector, θj (At , kt , Kt ) dj = θi (At , kt ) di = θt (At , kt , Kt ) ≡ Θt R R for labor service in underground sector, (1−θj (At , kt , Kt ))dj = (1− θi (At , kt ))di = 1 − θt (At , kt , Kt ) ≡ 1 − Θt R R for consumption cj (At , kt , Kt ) dj = ci (At , kt ) di = ct (At , kt , Kt ) ≡ Ct R R for investment z j (At , kt , Kt ) dj = z i (At , kt ) di = zt (At , kt , Kt ) ≡ Zt R R for capital k j (At , kt , Kt ) dj = k i (At , kt ) di = kt (At , kt , Kt ) ≡ Kt The economy satisfies conditions for existence and uniqueness of the Equilibrium as detailed in Prescott and Mehra (1980), to which we refer for details. To complete the characterization of the equilibrium, Proposition 1 proves that we have an interior equilibrium. Proposition 1 (Interior Solution) Here we show that a Rational Expectation Equilibrium for this model involves interior solutions. Proof. There are two possible corner solutions, the first θt = 0 is discussed in Claim 1, and the second θt = 1 in Claim 2. We prove both by contrapositive argument. 12 Claim 1: θt = 0 is not a REE. Suppose not, i.e. θt = 0 is a REE. If this is the case, it must satisfy profit maximization (equations (4) and (5)), utility maximization (equations (10) and (9)), and market clearing conditions. From (5) we have that as long as θt → 0 then wt → ∞. Substituting this into equation (10), the only value of θ coherent with this price is θ = 1. Labor market does not clear: hence θt = 0 cannot be a REE. Claim 2: θt = 1 is not a REE. Suppose not, i.e. θt = 1 is a REE. We use the same argument of Claim 1. From equation (10) when θt = 1 then wt → −∞ and, from equation (5) there are no values of θt ∈ (0, 1) that satisfy this condition. Again, market clearing conditions are not satisfied for labor services, and thus θt = 1 cannot be a REE. Substituting the Equilibrium conditions and the Government budget constraint into the first order conditions, we obtain a non-linear system of stochastic difference equations that defines the full set of feasible equilibrium allocations. Being highly non-linear, the system has no closed form solution. To study its stochastic properties we apply the well known procedure developed by King Plosser and Rebelo (1988a, b). In other words, we assume certainty equivalence, we linearize the system around its steady state, and we solve it applying linear approximations (e.g. Campbell 1994; Uhlig 1999). 3 Underground Economy Vs Home Production Before proceeding to the analysis, it is interesting to compare the theoretical structure of our model with household (home) production models.17 We focus on four, selected, issues: the commodities’ number and 17 Home production has been part of standard labor paradigm. Fundamental references include Becker (1965), Pollak and Watcher (1975), and Gronau (1977) and (1986)). Only recently has been introduced into macro models. However, the literature is quite large: see Benhabib, Rogerson and Wright (1991) for a survey, or among the many Rios Rull (1993), McGrattan, Rogerson and Wright (1992), Fisher 13 their substitutability, the financing of capital investment, the insurance opportunities offered by the second sector, and the different cyclical properties between home production and underground activities. First, consider the number of consumption goods and their substitutability. In the home production class of models there exist two goods, denoted as market and non-market commodities, each of which is produced with a sector specific technology. In addition, the preference specification allows for different degrees of substitutability between market and non-market goods.18 In contrast, in the model with underground sector there exist only one homogenous good, which, however, is produced using two different technologies: one associated with market sector, and the other with underground sector. In this environment it is natural to focus on the case of perfect substitutability between market-produced final output and underground-produced one. The second difference concerns the financing of investments. In home production models only market-produced goods can be consumed and invested, either into market capital or into non-market capital. There are no uses for home production output other than consumption - it cannot be sold or transformed into capital, for example, the way that market-produced output can. In the underground economy model, however, there exists only one capital stock (invested in the market sector), but market and non-market-produced output can be transformed into market capital, without any adjustment cost. The underground sector offers an additional channel for financing capital stock accumulation, and an additional dimension along which firms can employ the available labor supply.19 Summarizing, while home production model is a legitimate two sector model, the underground economy model could be more appropriately defined as a two technology model, since the same good is produced using two different technologies. Alternatively, (1992), and Fung (1992). 18 It is customary, in this literature, to consider the version with perfect substitutability as the benchmark simulated economy. 19 Technically speaking, the specification of consumer intertemporal feasibility constraint, equation (7), incorporates this feature. 14 we could define it as a 2-cycle model, given the cyclical properties of the market and the underground sectors. In addition, an underground sector offers profit smoothing opportunities for firms, and insurance opportunities for consumers. More precisely, firms can smooth their profits by a proper allocation of labor demand between the two sectors, on a period by period base. In addition, consumers can smooth not only consumption, by substituting over time consumption and investments, but also income, by allocating their labor supply across sectors, on a period by period base.20 In the model with underground sector consumers have two sources of income, which, being countercyclical, offer insurance against bad times (section 5.3 offers a deeper discussion). This mechanism is absent in models with home production. Finally, Ingram et al. (1997) find that hours spent in home production are acyclical. It is very important to notice that this implies that during recessions home production models predict that workers may adjust by switching into leisure, whereas a model with underground activities predicts a switch into underground activities. Difference is that in our class of model, non-market income increases during recessions, mitigating slumps, by offering insurance opportunities to household. Again this mechanism is not present in home production models. 4 Model Calibration The model is calibrated for the Italian economy because it presents a large underground sector, and it allows to better appreciate its impact on the overall economy. Needless to say, this analysis is addressed to European countries like Belgium, Denmark, Greece , Portugal and Spain, as Table 1 confirms. Our calibration is based on seasonally adjusted ISTAT series from 1970:1 to 1996:4, expressed in constant 1995 prices. 20 Needless to say, income smoothing is a device to smooth consumption over time. 15 Consumption is approximated by households’ final expenditures, and output definitions are approximated by the corresponding GDP definitions. Since Italian aggregate GDP, as well as GDP of the other European countries, contains an estimate of a hidden sector, we decompose it into the market and the underground components by using the series presented in Bovi (1999). Finally, all variables are transformed in logarithms, and detrended using the Hodrick-Prescott filter. The system of equations we use to compute the dynamic equilibria of the model depends on a set of 12 parameters. Six pertains to household preferences, (q, h, f, η, γ, β), four to the structural-institutional context (the probability of a firm being detected p, the surcharge factor s, the equilibrium income and corporate tax rates t and τ ), and the remaining two parameters to technology (the capital elasticity α, and the capital depreciation rate δ). The fact that the data on the underground economy is difficult to obtain substantially complicates the calibration. Because we are not aware of other studies which calibrate the parameters of a general equilibrium model augmented with a non-market sector, we precisely detail our calibration procedure below. A starred parameter denotes the precise calibrated value. 1. The probability of being detected, p. We calibrate this parameter by estimating the unconditional mean of the ratio of number of inspected firms to their total number, i.e. p̃t = Inspected F irms at t 21 T otal N umber of F irms at t . For Italy, as well as for the major- ity of countries, only a portion of this data is publicly available. For the Italian economy, the Ministry of Labor reports that the number of inspected firms has been 118,119 in 2000, 106,307 in 1999 and 95,676 in 1998. The overall number of firms in the Italian economy has been 4,639,393 in 2000, 4,472,375 in 1999 and 4,311,369 in 1998. As suggested above, we first compute the probability of being detected in each year, p̃t , and then we estimate 21 Note that an inspected firm is not necessarily convicted of evasion and therefore fined. Since inspections are based either on private information of Institutions, or randomly, it may happen that behavior of a perfectly honest firm will be inspected. 16 the aggregate probability as p∗ = omy p∗ = 0.03.22 1 T PT t=1 p̃t . For the Italian econ- Even though this is not an efficient estimate, it represents the best possible calibration for this parameter, given the available data. 2. The surcharge factor s, the income tax rate t, and the corporate tax rate τ . The parameter s represents the surcharge on the standard tax rate that a firm, detected employing workers in non-market sector, must pay. According to the Italian Tax Law (Legislative Decree 471/97, Section 13, paragraph 1) the surcharge equals 30 percent of the statutory tax rate if the firm pays the fine when detected, or 200 percent when the firm refuses to pay.23 We present results for s∗ = 1.30. In Italy, corporations are subject to a progressive tax rate. A tax rate of 19 percent is applied to the share of profits that represents 7 percent of the firm’s capitalization; the remaining portion is then subjected to an increased tax rate of 36 percent. We calibrate the steady state value of the corporate tax rate as the average of these two numbers, i.e. t∗ = 0.275. The personal income tax system is more complex, since we have five tax rates, spanning from 18.5 percent to 45.5 percent.24 The calibration of the income tax rate may be undertaken in two ways. It may be estimated as the average tax rate, weighted by the relative share of population in each income class. It may also be estimated as the tax rate associated with the average income of the working population (Adults 15-64 years old). We rely on 22 These data are available at the web site of the Italian Ministry of Labor, at the URL http://www.minlavoro.it/Personale/div7-conferenzastampa 01032001.htm. 23 In this case the firm will prosecuted under Criminal Law perspective, and if condemned pay 200 percent. 24 More precisely, the structure of the tax rates is the following as of 2001. For incomes less than 10,331 Euros tax rate is 18.5 percent, for incomes between 10,331 Euros and 15,496 Euros tax rate is 25.5 percent, for incomes between 15,496 Euros and 30,992 Euros tax rate is 33.5 percent, for incomes between 30,992 Euros and 63,283 Euros tax rate is 39.5 percent and, eventually, for incomes above 63,283 Euros tax rate is 45.5 percent. More details at the web-sites www.finanze.it or www.tesoro.it. 17 the second procedure and since the average income equals 18,246 Euros we estimate the income tax rate at 33.5 percent. 3. The steady state value of non-market sector share, 1 − θ. To calibrate this parameter we refer to Schneider and Enste (2000) who estimate the share of the non-market sector for a panel of OECD countries. The value for the Italian Economy, 1 − θ∗ = 0.265, is also consistent also with Mare’s (1996) estimates. 4. The preference parameters, q and β, the capital share, α, and the capital depreciation rate δ. These parameters are set to values commonplace in this literature (e.g. Fiorito and Kollintzas, 1994, or Censolo and Onofri, 1993). More precisely, we set q ∗ = 1, β ∗ = 0.98 and δ ∗ = 0.025. 5. Stochastic Shocks autocorrelation coefficients, ρm , ρu , ρt , ρτ and innovation amplitudes, σm , σu , σt , στ . The ρ0 s are set to .90 and the σ 0 s to 0.003. As we stress in next section, these val- ues are much lower than the standard ones (see King and Rebelo, 1999). This means that the model has a particularly efficient amplification mechanism which allows us to employ very small shocks (Section 5.3 offer more details). 6. Preference parameters h, f, η and γ. The calibration of these parameters is a not easy (see Cho and Cooley, 1994). We select them to match four moments: the ratio between standard deviation of total output σ(yttot ), and the standard deviation of total consumption, σ(ctot t ), the correlation between total output tot and total consumption ρ(ctot t , yt ), the correlation between unu derground production and total consumption ρ(ctot t , yt ), and the correlation between market production and total consumption m ∗ ∗ = 1.99, ρ(ctot t , yt ). The calibrated values are h = 0.55, f η ∗ = 0.40, γ ∗ = 3.00.25 25 Cho and Cooley (1994) calibrate these parameters using a similar procedure for the United States, and choose h = 6.0, f = 0.87, η = 0.62, γ = 2.00. Note, however, that their formulation of the model addresses issues different from matching 18 5 Simulation Results Here we describe how well our model accounts for aggregate fluctuations, and we compare its performances with selected alternative approaches (section 5.1). Next, the economic mechanisms and the driving forces operating in our model are analyzed and interpreted by studying the Impulse Response Functions (IRF) to the sectoral and the aggregate shocks (section 5.2). Eventually, we focus our attention on the model propagation mechanism (section 5.3). 5.1 Numerical Simulations Table 2 illustrates how adding the underground sector implies a much better fit to the data. The tables displays the relative ability of three different models in order to match the major stylized facts characterizing the cyclical behavior of Italian economy over the sample 1970:11996:4.26 Its first part reports the actual stylized facts of the economy, while the following blocks present the corresponding business cycle properties, as generated by a Hansen (1985) indivisible labor version of the stochastic growth model calibrated for Italian economy, a model incorporating a monopolistic union (Chiarini and Piselli, 2001), and our two sector model. Statistics are generated from 100 simulated time series of length 104 quarters. A star denotes simulated moments, while a hat moments estimated from actual data. Table 2 Among the reported statistics, it is interesting to note how market GDP is much more volatile (σ̂ym = 2.27) than the total and underground counterparts (σ̂yu = 1.11 and σ̂ytot = 1.47 respectively). Further, consumption is positively correlated with the market and the aggregate components of GDP (ρ̂(c, ym ) = 0.95 and ρ̂(c, ytot ) = 0.80), moments for the market and the non-market sectors. Specifically, they study the implications of this kind of utility function for the volatility of hours, employment and productivity in the United States. 26 The comparison is particularly interesting, because, all the selected models incorporate some mechanism that substantially amplifies productivity shocks. 19 while it presents a negative correlation with the underground part (ρ̂(c, yu ) = −0.47). It is also interesting to compare our model’s performance with actual data along the so called consumption volatility puzzle, the productivity puzzle and the employment variability puzzle.27 First, notice that our two-sector model replicates efficiently consumption volatility (precisely, σ̂ctot = 1.24 and σc∗tot = 1.17 (0.15)). This is an interesting improvement upon the indivisible labor version, and the union model.28 We argue that this improvement is due to the introduction of the underground sector. In particular, in the model there are two income sources (market and non-market income), which are both highly volatile, and negatively correlated. This implies that, on the one hand, consumers can smooth more easily consumption, by a proper labor supply allocation between sectors, but, on the other hand, that they are subject to two sources of fluctuations. For the parameterization presented in section 5, the second effect dominates. Moreover, our model matches, as well as the Chiarini and Piselli (2001) model, the correlation between market labor and productivity (precisely, ρ̂(nt , πt ) = 0.19 and ρ∗ (nt , πt ) = 0.04 (0.16)). The economic mechanism, however, differs significantly between the two approaches. To understand the economic implications, Figure 2 describes the labor market response after an unexpected increase in market productivity, Mt . 27 The employment variability puzzle refers to the fact that employment (or total hours worked) is almost as variable as output, and strictly procyclical, something which is difficult to replicate in a standard neoclassical model. The productivity puzzle looks at the correlation between labor productivity and GDP. If productivity shocks drive the cycle, by construction the productivity will be highly correlated with the employment. The puzzle is that productivity and employment are negatively correlated for most economies. As reported by Stadler (1994) this correlation is negative of zero for almost all the countries. Finally, the consumption volatility puzzle (Cochrane, 2001) refers to the fact that consumption volatility generated by stochastic growth models is often too small relative to the data. 28 Precisely, the former does fairly well in matching the employment volatility, but it is limited in replicating other business cycle facts. The latter has a better fit compared to Hansen version, but it still generates a low consumption volatility nion = 0.29). (precisely, σctot = 1.24 and σ̂cUtot 20 Figure 2 To begin, notice that the labor market of our model is characterized by two pairs of demand and supply schedules, one for the market sector, and the other for the underground economy. After the productivity shock, market labor demand shifts out (from point M0 to M1 ), and labor supply increases, initially along its schedule. This shock does not affect underground labor demand, while it does affect the non-market labor supply schedule, which shifts to the left (from point U0 to U1 ). This step is crucial. Since the two labor supply schedules move in opposite directions, the market labor supply schedule shifts out (from point M1 to M2 ), further increasing employment in market sector and reducing the wage. This happens because households allocate a share, θ, of total labor supply to the market sector, and its complement, 1−θ, to the underground economy. In other words, when the underground labor supply share decreases, the market sector counterparts has to increase. This mechanism reduces the correlation between labor productivity and GDP, and thus improves the empirical performances of our model along the productivity puzzle. In the next section we provide further evidences on labor reallocation by using Impulse Response Functions to the sectoral and aggregate disturbances. Finally, while each of the three models generate sufficient employment volatility, only our two-sector model produces adequate labor productivity volatility (precisely, σ̂π = 2.78 and σπ∗ = 2.94 (0.17)). Since labor productivity volatility is related to labor volatility itself, the outcome produced by our model should be related to the fact that labor enters linearly into underground sector production function (see equation (1)). This structure is meant to represent an aspect peculiar to underground activities, where labor is highly flexible and elastic. As a results it produces volatility in labor services, and consequently, to labor productivity. It is interesting to underline the difference between this mechanism and Hansens’s (1985): the former uses a linearity into the production function, that is on the labor demand side, while the latter makes, roughly speaking, labor entering linearly into utility 21 function, that is on the supply side. Summarizing, the introduction of an underground sector is relevant, because the economic mechanisms and the driving forces we present here are generally absent in the standard Real Business Cycle models. It is likely, that for economies with an empirically relevant unofficial sector, standard RBC model overlooks the relationship between the market and the underground sectors generated by innovations in the sectoral and the aggregate shocks, as we explain more in details in the next section. 5.2 Sectoral and Aggregate Shocks In the model there are two sectoral shocks, the market productivity shock (Mt ) and the underground technology shock (Zt ); in addition, there are two aggregate shocks that increase income and corporate tax rates (τt and tt ). In order to understand the dynamics of the economy when the equilibrium is disturbed by these exogenous shocks, we analyze the IRF generated both by the sectoral and the aggregate disturbances. Figure 3 describes the model response when either the market or the underground sector productivities increase exogenously by a one standard deviation innovation (Panel A and Panel B, respectively). Figure 3 Consider first Panel A. The marginal productivity of input factors increases (decreases) in market (underground) economy, attracting (transferring) resources from (to) underground (market) sector. As there is more employment and more capital in this sector, and a decrease in the employment in the underground one, a market productivity shock implies an increase of the aggregate output. Note, however, that the impact on aggregate production is partially offset by a reduction in the underground-produced output. Since market sector is relatively larger in size than its underground counterpart, households 22 have more resources, which are allocated between consumption and investments. The previous picture, however, is reversed when the economy is hit by a one-standard deviation innovation on underground sector productivity (Panel B). This shock may be motivated as representing several inputs that often are left out of the model for convenience, such as management skills, creativity, better workplace organization, etc. Elements that exist in the underground activities, and that are capable to rise corresponding labor productivity.29 After the shock, the employment share in the underground economy rises, pulling down the share of workers employed in the market sector. Notice, that as market employment and capital fall, the employment increase in the underground sector is too small to compensate its reduction in the market economy.30 Here the capital stock reduction is driven by a drop in the marginal productivity of invested capital, caused by the reallocation of labor inputs to the underground sector. Figure 3 also shows that sectoral shocks have asymmetric aggregate effects on output and labor shares. Consider, for example, the impact response of aggregate output after the sectoral shocks: an increase in market productivity raises it 29 More precisely, the productivity shock idiosyncratic to the underground sector can be tied, for example, to the following three arguments. First, since labor in the underground sector is very flexible, and the worked hours are voluntary, we argue that the employee’s motivation is stronger. Second, a significant part of the underground labor force is made of immigrants, which try to be as much productive as they can, to be hired as a regular workers. Notice that immigrants usually enter western European countries with temporary visas, which are converted into permanent ones only when they prove to be regularly employed. The waves of immigrants can be interpret as temporary shocks to underground sector. Finally, there are young pensioners entering the underground labor market. These workers have a high productivity, but choose to work in the underground sector for earning an additional income, keeping at the same time their pensions. Needless to say, this would not be possible if they were hired under a regular labor contract. 30 This is a direct consequence of the structure of the labor market. Indeed, in equation (1) we normalize the aggregate employment to unity, which implies that a sectoral shock generates, for what concern labor services, only a reallocation between the two sectors. All resources take away from a sector are transferred to the other; in this context the relative size of the two economies has an important role in shaping aggregate fluctuations. A development of the actual model could generalize the actual set-up introducing the aggregate employment as an additional control variable. 23 1.8 percent above its steady state, while it falls below its steady state level by less than 1 percent after a shock in the underground economy. Since the rise of the burden of taxes and social security contributions is one of the most cited causes of the growth of underground economy, government taxation plays a relevant role in the allocation of output and labor input between these sectors. Our interest in this analysis is motivated by the desire to assess the cyclical properties of taxation policies, and their implications in term of resource reallocation. More precisely, we investigate how an unexpected increase in corporate and personal income taxes affects production and labor allocation between the market and the underground sectors. Figure 4 encapsulates the IRF after a one-standard deviation increase in the corporate tax rate tt (Panel A), and in the income tax rate τt (Panel B). Figure 4 A temporary rise in the corporate tax rate, tt , reduces production and labor input in the market sector, enhancing employment and output in the underground sector. The official labor market share is instantaneously below its steady state level by 6 percent, while the share of underground labor rises almost symmetrically. Investment falls below its steady state pre-shock level by 22 percent, and the production activity in the official economy drops by about 3 percent, while aggregate output falls below its steady state by 2 percent.31 Notice that the rise in the unreported enterprisers thwarts to some degree the recession effects of the rise in taxation. The negative impact of the higher taxation on output and income induces firms and households to work more in the underground sector, highlighting a strong reallocation effect between the two sectors. An aggregate shock on corporate tax pushes the economy into a recession, which is, however, mitigated by the existence of the underground sector that offers an insurance or risk 31 The volatility of the investment seems higher than the standard RBC models: see, for example Baxter and King (1993), or Ramey and Shapiro (1997). 24 sharing opportunity, through the labor reallocation toward that sector. We could think to the underground sector as offering an insurance channel, alternative to financial markets, available to people facing, for example, liquidity constraints. Individuals involved in underground activities usually face restricted market participation. The reaction of the economic system after a raise of personal income tax, τt , does not differ, qualitatively speaking, from the previous scenario. Notice that the impact responses of the variables are just diminished in size, compared with Panel A, and with a standard RBC model, too (e.g. King, Plosser and Rebelo, 1988a). In our simulation, investment’s peak impact response reaches a decline of about 3.5 percent, and consumption drops by about 1 percent. That is because the consumers can reallocate consumption and labor, not only inter-temporally, but also intra-temporally between the two sectors, reducing the income loss generated by the fiscal policy. More precisely, by shifting resources to the underground sector, consumers are able to reduce their taxable income, as they keep constant their effective income. This intra-temporal smoothing opportunity is reflected into the IRF as a softened response to stochastic disturbances. Comparing this outcome with the previous one (Figure 3), we argue that consumers reallocate resources intertemporarly more easily than firms do. That happens because the latter ones invests capital in the market sector, which, given a concave production function (see equation 1), slows down the labor reallocation mechanism. In addition the probability of being discovered, and fined, reduces firms’ incentives to move large amounts of resources out of the market sector. This analysis leads us to conclude that aggregate RBC models for economies with a significant underground sector cannot disregard these activities for understanding fiscal policy effects and labor reallocation over the cycle. Indeed, if we were to ignore this sector, we would abstract from some important aspects, from a theoretical and empirical perspective. The actual RBC research shows that the introduction of additional sources of variation, such as exogenous fiscal policy shocks, 25 helps to improve the theoretical models predictions (Christiano and Eichenbaum, 1992; Braun, 1994; McGrattan, 1994; Edelberg, Eichenbaum, Fisher, 1999). But assessment and comparisons between these models and the data may often be limited by the lack of untaxed activities. Hence, overlooking the underground sector may conduct to a misleadingly representation of the vastly complex tax effects over the cycle. 5.3 A Better Propagation Mechanism King and Rebelo (1999), in their well known survey on Real Business Cycle models, discuss extensively the central role of productivity shocks in driving the business cycle.32 They also stress how the model performances rely on large and highly persistent technology shocks. To generate macroeconomic series consistent with the US and the European data, the RBC models require a considerable variability in productivity, and a serial correlation parameter of the stochastic component of productivity near one. But, at the same time, a well known shortcoming of the standard dynamic general equilibrium model is its weak propagation mechanism, as pointed out by Cogley and Nason (1995), or more recently by Chang, Gomes, Schorfheide (2001) among the others. King and Rebelo (1999) identify four mechanisms that substantially amplify productivity shocks, and lead to stronger comovements of the main variables. The first one makes output respond more elastically to productivity shocks, the second and the third ones rely on a larger elasticity either of the labor demand or the labor supply, while the fourth is based on the non-separability between consumption and leisure (or labor) into the utility function. The propagation generated by our model is not based on any of the listed, but it depends on an original mechanisms, peculiar to un32 Note, however, that the notion that technological shocks are related with business cycles was called into question by several contributions. Using different methodologies, Gali (1999), Shea (1998), and Basu, Kimball and Fernald (1999), and more recently Nevill and Ramey (2002), present similar results: positive technological shocks lead to decline in labor inputs. 26 derground activities. Indeed, its introduction into a stochastic growth model does not affect either the slope of labor demand and supply schedule, or the elasticity of output to shocks, but introduces a propagation mechanism triggered by the reallocation of labor services between the two sectors. In the light of the results stylized in Figure 2, and presented in Figure 3 and 4, when a shock hits one of the two sectors, it is transmitted to the other, which returns an additional, smoothed, impulse to the former sector. By this end, the impact of a shock is propagated within the economy, which necessitates of smaller stochastic disturbances to generate series consistent with the actual data. It is particularly welcome that we obtain these results even if we use a logarithmic utility function for consumption, and small shocks. Following Cogley and Nason (1995) we define an improvement in the propagation mechanism of a stochastic growth model in the sense of necessitating a lower autocorrelation coefficient for the process of stochastic disturbances, and a smaller standard deviation of the innovations (defined in Section 2.1.4) for replicating business cycle facts. To highlight this feature, we compare, in Table 3, our model parameterization with the one used in the standard benchmark model (Hansen, 1985), with the parameterization used in the so-called high substitution class models (see King and Rebelo, 1999), with the parameterization of a model which uses a utility function like ours (see Cho and Cooley, 1994), and with a home production model (Benhabib, Greenwood and Wright, 1996). Table 3 It is interesting to note that while the standard RBC models need significantly larger shocks (standard deviation of the innovation process, σ = 0.00712) and a high autocorrelation coefficient for the shock (ρ ' 0.99), the high substitution economies reduce the first of these magnitudes to about, σ = 0.0012 but still need a high AR(1) coefficient (ρ ' 0.99). The latter class of models also requires a high risk 27 aversion parameter (q = 3). The Cho and Cooley (1994) model does not require a high relative risk aversion coefficient, and even if it has a smaller autocorrelation coefficient (ρ ' 0.95) , it still needs a very high standard deviation for the innovation process, σ = 0.0102. Our model is, instead, able to match properly the data with a small amplitude of the innovation process (standard deviation of the innovation process, σ = 0.003), with a better amplification of the shock across time (ρ ' 0.90), and without assuming a high risk aversion (q = 1). The last 2 column of Table 3 present the variance of the stochastic shock σShock 2 (which differs from that of innovation process, σInnovation ), as gener2 = ated by the different models. It is computed as σShock 2 σInnovation 1−ρ and offers an additional perspective on the model comparison. 6 Conclusions In this paper, we use a general equilibrium production model with an underground economy to generate quarterly data on unobservable variables. The responses of goods produced in the underground sector and labor engaged in the underground market, along with the counterpart variables in the official market, are analyzed under several productivity and taxation stochastic shocks. We have four major findings. First, the mechanism of reallocation of labor and production between the official and the underground sectors over the cycle can resolve several labor market puzzles, displaying more realistic real wageemployment and productivity-output correlations without calling for a high degree of intertemporal substitution over the business cycle. Second, this reallocation behavior is influenced by the productivity shocks and taxation policies. Large fluctuations in the sectors are associated with restrictive taxation policies on income, output and social security payments. Third, investment experiences large variability, without necessity of large shocks. In addition, consumption response is smooth, under a logarithmic utility function. In other words, our model requires smaller 28 stochastic shocks than those required by the standard RBC models for matching selected moments of the actual economies. This means the model’s structure is characterized by a higher amplification of the productivity shock by the model’s structure. Finally, we feel that the properties of the constructed two-sector model deserve a particular attention. In fact, new and interesting results arise, when we deal explicitly with cyclical behavior that distinguishes between market and underground labor input. Unlike the standard RBC model, or economies with home production, here we generate two distinct cycles of the activity, each affecting consumption and investment outcomes. References [1]Becker G. S., 1965, A Theory of Allocation of Time, Economic Journal, 75, 493-517 [2]Basu S., K. Miles and J Fernald, Are Technology Improvements Contractionary? 1999 manuscript. [3]Baxter M. and R. King, 1993, Fiscal policy in general equilibrium, American Economic Review 83, 315-334. [4]Benhabib J., R. Rogerson and R. Wright R., 1991, Homework in Macroeconomics: Household Production and Aggregate Fluctuations, Journal of Political Economy 99, 1166-1187. [5]Bovi M., 1999, Un miglioramento del metodo di Tanzi per la stima dell’economia sommersa in Italia, ISTAT, Quaderni di Ricerca 2, 5-51. [6]Braun R.A., 1994, Tax Disturbances and Real economic Activity in the Postwar United States, Journal of Monetary Economics 33, 441-62. [7]Burnside C., M. Eichembaum and S.T.Rebelo, 1995, Capital Utilization and Returns to Scale, NBER Macroeconomics Annual, MIT Press, 67-110. [8]Campbell J.Y.,1994, Inspecting the mechanism, Journal of Monetary Economics 33, 463-506. [9]Chang, Gomes, Schorfeide, 2001, Learning by Doing as Propagation Mechanism, forthcoming American Economic Review [10]Chiarini B. and P. Piselli, 2000, Aggregate Fluctuation in a Unionized Labor Market, Working Paper 2, University of Naples Istituto 29 Universitario Navale, http://economia.uninav.it/ise/wp.htm [11]Cochrane, J.H., 2001, Asset Pricing, Princeton University Press [12]Christiano L. and M. Eichembaum, 1992, Current Real Business Cycle theory and aggregate labour market fluctuations, American Economic Review 82, 430-450. [13]Cho J.O. and T. F. Cooley, 1995, The Business Cycle with Nominal Contracts, Economic Theory 6, 13-33. [14]Cho J.O. and T.F. Cooley, 1994, Employment and Hours over the Business Cycle, Journal of Economics, Dynamics and Control 18, 411-432. [15]Cho J.O. and R. Rogerson, 1988, Family Labour Supply and Aggregate Fluctuations, Journal of Monetary Economics 21, 233-245. [16]Cogley T. and J.M. Nason, 1995, Output Dynamics in Real Business Cycle Models, American Economic Review 85, 492-511. [17]Danthine J.P. and J.B. Donaldson, 2001, Output Dynamics in Real Business Cycle Models, Decentralizing the Stochastic Growth Model, mimeo, Columbia University [18]Edelberg W, M. Eichenbaum, J. Fisher, 1999, Understanding the Effects of a Shock to Government Purchases, Review of Economic Dynamics, 2, 1, 166-206 [19]Feige E.L., 1989, The Underground Economies. Tax Evasion and Information Distortion, (Cambridge University Press; Cambridge). [20]Fiorito R. and T. Kollintzas, 1994, Stylized facts of Business Cycles in the G7 from a Real Business Cycles Perspective, European Economic Review 38, 235-269. [21]Fisher J.D.M., 1992, Relative Prices, Complementarities and Comovements, Manuscript, Northwester University Reproduced [22]Fung S., 1992, Inflation, Taxation and Home Production in a Real Business Cycle Model, manuscript University of Western Ontario. [23]Gali J., 1999, Technology, Employment, and the Business Cycle: Do Technology Shocks Explain Aggregate Fluctuations, American Economic Review, 89, 249-271. [24]Giles D, 1999, Measuring the Hidden Economy: Implications for Econometric Modelling, Economic Journal, 109, 456, 370-80. [25]Greenwood J. and Z. Hercowitz, 1991, The Allocation of Capital and Time over the Business Cycle, Journal of Political Economy 99, 1188-1214. [26]Gronau, R, 1977, Leisure, Home Production, and Work-The Theory of the Allocation of Time Revisited, Journal of Political Economy, 85, 6, 1099-1123 30 [27]Gronau, R, 1986, Home Production-A Survey, Handbook of labor economics, 1, 273-304 [28]King R.G., C.I. Plosser and S.T. Rebelo, 1988a, Production, Growth and Business Cycles: I. The Basic Neoclassical Model, Journal of Monetary Economics, 21, 195-232. [29]King R.G., C.I. Plosser and S.T. Rebelo, 1988b, Production, Growth and Business cycles: II New directions, Journal of Monetary Economics 21, 309-342. [30]King R.G. and S.T. Rebelo, 1999, Resuscitating Real Business Cycles, in Taylor J.B. and Woodford M. (eds.), Handbook of Macroeconomics Vol.1 (Elsevier Science, Amsterdam). [31]Hansen G.D., 1985, Indivisible Labour and Supply and the Business Cycle, Journal of Monetary Economics 16, 309-327. [32]Hodrick. R. J and E. Prescott, 1997, Postwar U.S. Business Cycles: An Empirical Investigation, Journal of Money, Credit, and Banking, 29, 1, 1-16. [33]Ingram B.F., N.R. Kocherlakota and N.E. Savin, 1994, Explaining Business Cycles. A Multiple-Shock Approach, Journal of Monetary Economics 34, 415-428. [34]Lucas R.E.Jr., 1988, On the Mechanics of Development Planning, Journal of Monetary Economics 22, 3-42. [35]Nevill F. and V. Ramey (2002), Is the Technological Driven Business Cycle Hypothesis Dead?, NBER Working Paper, 8726 [36]Mare’ M., 1996, L’evasione in Italia e nei paesi OECD: evidenze empiriche, determinanti ed effetti economici, Moneta e Credito 49, 393-443. [37]McGrattan E.R., 1994, The Macroeconomic Effects of Distortionary Taxation, Journal of Monetary Economics 33, 559-71. [38]McGrattan E.R., R. Rogerson and R. Wright, 1997, An Equilibrium Model of the Business Cycle with Household Production and Fiscal Policy, International Economic Review 38, 267-90. [39]Olson M., 1982, Environmental Indivisibilities and Information Costs: Fanaticism, Agnosticism, and Intellectual Progress, The American Economic Review, Papers and Proceedings of the Ninety-Fourth Annual Meeting of the American Economic Association, , 72, 2, 262-266. [40]Pollak R.A, M.L. Watcher, 1975, The Relevance of the Household Production and its Implications for the Allocation of Time, Journal of Political Economy, 83, 255-77 [41]Prescott E. C. and R. Mehra, 1980, Recursive Competitive Equilibrium: the Case of Homogenous Household, Econometrica, 1365-79 31 [42]Ramey V.A. and M.D. Shapiro, 1997, Costly Capital Reallocation and the Effects of Government Spending, NBER Working Paper Series, http://www.nber.org/papers/w6283 [43]Rios-Rull, J-V, Working in the Market, Working at Home, and the Acquisition of Skills: A General-Equilibrium Approach, American Economic Review, 83, 4, 893-907 [44]Shea J., 1998, What Do Technology Shocks Do?, NBER Macroeconomics Annual, 275- 310. [45]Stadler G.W., 1994, Real Business Cycle, Journal of Economics Litterature XXXII, 1750-1783. [46]Schneider F. and D. Enste, 2000, Shadow Economies: Size, Causes, and Consequences, Journal of Economic Literature XXXVIII, 77-114. [47]Spiro P. 1994, The Underground Economy: Toward a More Balanced View of Alternative Methodologies Canadian Business Economics, 2, 4, 18-21. [48]Stokey N. and R.E. Lucas with E.C. Prescott, 1989, Recursive Methods in Economics Dynamics, (Harvard University Press; Cambridge MA). [49]Tanzi V., 1983, The Underground Economy in the United States: Annual Estimates, 1930-80, International Monetary Fund Staff Papers, 30, 2, 283-305. [50]Tanzi V., 1980, Inflationary Expectations, Economic Activity, Taxes, and Interest Rates, The American Economic Review, 70, 1, 12-21. [51]Thomas J.J., 1992, Informal Economic Activity in LSE Handbooks in Economics, (Harvester Wheatsheaf; London). [52]Thomas J.J., 1999, Quantifying the Black Economy: ’Measurement Without Theory’ Yet Again?, Economic Journal 109, 381-89. [53]Uhlig H., 1999, A Toolkit for Analysing Nonlinear Dynamic Stochastic Models Easily, in R. Marimon and A. Scott (eds) Computational Methods for the Study of Dynamic Economies, (Oxford University Press; Oxford). [54]Uzawa H., 1965, Optimal Technical Change in an Aggregative Model of Economic Growth, International Economic Review 6, 18-31. 32 Appendix A 1 Proof and Derivations Proof of Lemma 1 (Production set). Here we show that production function (2) satisfies a list of commonly assumed properties of production sets, denoted by Y . Precisely, they are: (I) Y is non empty, (II) Y is closed, (III) No-free lunch, (IV) Convexity. (I) trivial. (II) trivial. i (III) To prove that (2) satisfies no-free lunch notice that total output, ytot , i i dependes on capital, k , and labor, n , which is normalized to unity. Notice that θ and 1 − θ denotes the share of total labor allocated to market and non-market sector, respectively. Rewrite production function without ¡ ¢˙ ¡ ¢α ¡ i i ¢1−α i normalizing total labor: ytot nθ = M ki +Z(ni 1 − θti ). Hence i k i = ni = 0 ⇔ ytot = 0. (IV) easy. Proof of Lemma 2 (Price Vector). Suppose not, i.e. qtm 6= qtu . Assume, WLOG, that qtm > qtu . In this case only market-produced good will be produced: all resources are shifted to corresponding sector, labor included. This implies θ = 1. By proposition 1 we know that solution lies in the interior of the state space, and thus in a REE we cannot have qtm > qtu . An analogous argument rules out the case qtm < qtu . Proof of Lemma 3 (Existence and Uniqueness of the Solution). To prove the claim we rely on the key theorem in infinite dynamic programming, that is the contraction mapping theorem applied to the Bellman Equation. The critical theorem is due to Denardo (1967), and we report it for convenience. Theorem 1 (Denardo (1967)) If state-space is compact, β < 1, and payoff function u(k, K, A) is bounded above and below, than the map T J(k, K, A) = sup u(k, K, A) + βE(J(k 0 , K 0 , A0 )) is monotone in J, is a contraction mapping with modulus β in the space of bounded functions, and has a unique fixed point. In our model the state-space is compact, and β < 1. We just need to show (cj )1−q −1 (θtj )1+γ (1−θtj )1−η that payoff function u(cjt , θtj ) = t 1−q − h 1+γ (1 − θtj ) − f 1−η is 1 bounded above and below. Assume that cjt = θtj = 0 and compute u(0, 0) = f . To prove that function is bounded above we show that it is increasing − 1−η and concave. For this utility function this conditions is satisfied for a restricted set of parameters, which include our parametrization. First, we compute the Gradient: · ¸ · ¸ c−q uc J = = 2+γ −hθγ + hθ1+γ 1+γ − f (1 − θ)−η uθ where uc and uθ are the partial derivatives with respect to consumption, c, and market labor share, θ. Note, that, for c positive, uc > 0. Therefore, to have the Gradient positive we need uθ > 0. uθ = −hθγ + hθ1+γ Next, we compute the Hessian: · ¸ · ucc ucθ −qc−q−1 H= = 0 uθc uθθ 2+γ − f (1 − θ)−η > 0. 1+γ (A.1) 0 −hγθγ−1 + hθγ (2 + γ) + ηf (1 − θ)−η−1 ¸ where ucc and uθθ are second derivative with respect to consumption and market labor, respectively. uθc and ucθ are the mixed second derivative of the momentary utility function. Note, that, for q, c ≥ 0, ucc = −qc−q−1 ≤ 0, uθc = ucθ = 0 η−1 ≶ 0. Hence, to have the and that uθθ = −hγθγ−1 + 2hθγ + hθγ γ − ηf (1 − θ) Hessian definite semi-negative, we want uθθ to be non positive: −η−1 uθθ = −hγθγ−1 + 2hθγ + hθγ γ + ηf (1 − θ) ≤ 0. (A.2) When (A.1) and (A.2) the utility function satisfies the conditions for a unique maximum. Note that condition (A.1) and condition (A.2) are both satisfied for the parameters used in the baseline simulation (Table 2), and in the experiment with higher steady state tax rates. More precisely, the value of uθ is 1.0027 and the value of uθθ equals −1.5864. 2 Appendix B: Figures Figure 1: Cyclical properties of Market and Underground components 0.04 0.08 0.08 0.02 0.06 0.02 0.04 0.01 0.00 0.00 0.02 -0.04 0.04 0.00 0.02 -0.01 0.00 -0.02 0.02 0.04 -0.08 -0.03 0.04 Market Comp. 0.06 60 62 64 66 68 70 Underground Comp. 72 74 76 78 80 Market Comp. -0.12 0.06 82 70 U.S. Panel, Tanzi (1983) 75 80 Underground Comp. 85 90 -0.04 95 Italy Panel, Bovi (1999) 0.20 0.08 0.10 0.6 0.15 0.4 0.04 0.05 0.10 0.2 0.00 0.05 0.00 0.00 0.0 -0.04 -0.2 0.05 -0.08 -0.05 -0.4 0.10 Market Comp. 0.15 78 80 82 84 Undeground Comp. 86 88 90 92 -0.12 -0.10 94 Market Comp. Underground Comp. -0.6 60 62 64 66 68 70 72 74 76 78 80 82 84 New Zealand Panel, Giles (1999) U.K. Panel, Mare’ (1996) Figure 1. Series are presented in a dual scale plot, and are all detrended using Hodrick-Prescott (1997) …lter. U.S. Panel, Tanzi (1983): the market component is the GDP, while the underground component is the ratio of estimated underground economy to the total GDP. Italy Panel, Bovi (1999): the market component is the GDP, and the underground component is an estimated ”underground GDP”. New Zealand Panel, Giles (1999): the market component is the ratio of Taxation to total GDP, while the underground component is the ratio of estimated underground GDP to total GDP. UK Panel, Mare’ (1996): the market component is the GDP, while the underground component is the ratio of estimated underground economy to the total GDP 1 Figure 2: Labor Market Dynamics wage (net of taxes) NSmkt(0) NSu(1) NSu(0) NSmkt(1) M1 M0 Wage (gross of taxes) M2 U1 U0 NDmkt(0) NDmkt(1) NDu(0)= NDu(1) Market and Underground Employment Figure 2. The schedules on the LHS (grey) depicts underground labor market, while the schedules on the RHS (black) describe o¢cial labor market. Since underground demand and supply depend on the net of tax wage, while market schedules are function of gross of tax wage, we use a dual scale plot. The left scale refers to underground labor market, while the right one to o¢cial labor market. The arrows describe the dynamics of the two markets after a positive and temporary productivity shock in the market sector. U0 and M0 characterize the labor market equilibria before the shock, while (U1 ; M2 ) the equilibria during the shock. Since it is a temporary shock, in the long run the system converges back to (U0 ; M0 ). 2 Fig. 3: Impulse Response Functions after a sectoral productivity shock Panel A: Market Productivity Shock (M) Market Labor (*), Underground Labor (x) - shock to M 2 2 1.5 1.5 1 1 0.5 -0.5 -1 5 10 15 20 Quarters After Shock 25 30 -1.5 35 6 0 -0.5 0 7 0.5 0 -1 Consumption (+), Investment (x), Capital Stock (o) - shock to M 8 % deviation from S.S. 2.5 % deviation from S.S. % deviation from S.S. Market Output (*), Underground Output (x), Total Output (o) - shock to M 5 4 3 2 1 0 5 10 15 20 Quarters After Shock 25 30 0 35 0 5 10 15 20 Quarters After Shock 25 30 35 Panel B: Underground Productivity Shock (Z) Market Output (*), Underground Output (x), Total Output (o) - shock to Z Market Labor (*), Underground Labor (x) - shock to Z 1.5 Consumption (+), Investment (x), Capital Stock (o) - shock to Z 3 0 2.5 1 -0.5 2 0 -0.5 % deviation from S.S. % deviation from S.S. % deviation from S.S. -1 1.5 0.5 1 0.5 0 -0.5 -1.5 -2 -2.5 -3 -1 -1 -3.5 -1.5 -1.5 0 5 10 15 20 Quarters After Shock 25 30 35 -2 0 5 10 15 20 Quarters After Shock 25 30 35 -4 0 5 10 15 20 Quarters After Shock 25 Figure 3. The …gure shows the …rst 32 quarter response of market output, underground output, total output, market and underground labor, to a one standard deviation innovation to market productivity, Mt (Panel A), and to underground productivity, Zt (Panel B). The curves are the quarterly percentage deviations from a baseline scenario where all innovations are set to zero. 3 30 35 Fig. 4: Impulse Response Functions after a tax shocks Panel A: Corporate Tax Shock (t) Market Output (*), Underground Output (x), Total Output (o) - shock to t Market Labor (*), Underground Labor (x) - shock to t 4 Consumption (+), Investment (x), Capital Stock (o) - shock to t 8 3 0 6 -5 1 0 -1 % deviation from S.S. 4 % deviation from S.S. % deviation from S.S. 2 2 0 -10 -15 -2 -2 -20 -4 -3 -4 0 5 10 15 20 Quarters After Shock 25 30 -6 35 0 5 10 15 20 Quarters After Shock 25 30 -25 35 0 5 10 15 20 Quarters After Shock 25 30 35 Panel B: Income Tax Shock (tau) Market Output (*), Underground Output (x), Total Output (o) - shock to tau Market Labor (*), Underground Labor (x) - shock to tau 0.4 Consumption (+), Investment (x), Capital Stock (o) - shock to tau 2 0 -0.2 0.3 1.5 -0.4 0 -0.1 -0.2 -0.6 1 % deviation from S.S. 0.1 % deviation from S.S. % deviation from S.S. 0.2 0.5 0 -0.3 -1 -1.2 -1.4 -1.6 -0.5 -0.4 -0.5 -0.8 -1.8 0 5 10 15 20 Quarters After Shock 25 30 35 -1 0 5 10 15 20 Quarters After Shock 25 30 35 -2 0 5 10 15 20 Quarters After Shock 25 Figure 4. The …gure shows the …rst 32 quarter response of market output, underground output, total output, market and underground labor, to a one standard deviation innovation to corporate tax rates, tt (Panel A), and in income tax rate, ¿ t (Panel B). The curves are the quarterly percentage deviations from a baseline scenario where all innovations are set to zero. 4 30 35 Appendix C: Tables Table 1: Underground Economy for Selected OECD Countries Countries Australia Belgium Denmark France Greece Germany Great Britain Italy Portugal Spain USA Average OECD 1994-95 13.8 21.5 17.8 14.5 25.0 13.5 12.5 26.0 22.1 22.4 9.20 16.0 1996-97 13.9 22.2 18.2 14.8 26.0 14.8 13.0 27.2 23.0 23.0 8.8 16.9 Table 1. Sources: Schneider and Enste (2000). Numbers in the columns represent the average size (over the speci…ed) sample of the underground sector relative to the GDP. 5 Table 2: Business Cycle Properties of Italian Economy: Comparison across Models Actual Data variable ¾ ^ variable ¾ ^ variable ¾ ^ ytot ½(ytot ; variable) ^ ^(n; variable) ½ Indivisible Labori variable ¾?variable ¾? variable ¾? ytot ? ½ (ytot ; variable) ? ym 2.27 0.89 yu 1.11 -0.45 ytot 1.44 1.00 1.00 c 1.24 0.85 0.80 x 3.70 2.53 0.78 n 1.39 0.95 0.63 ¼ 2.78 1.90 0.36 0.19 ym - yu - ytot 1.45 1.00 c 0.29 0.20 x 3.44 2.37 n 1.27 0.88 ¼ 0.29 0.20 - - 1.00 0.67 0.99 0.99 0.99 0.09 ym - yu - ytot 1.42 1.00 c 0.30 0.21 x 5.82 4.09 n 1.28 0.90 ¼ 0.41 0.29 - - 1.00 0.38 1.00 0.96 0.49 0.04 ym 2.07 (0.22) 1.86 yu 1.94 (0.25) 1.33 ytot 1.45 (0.14) 1.00 c 1.17 (0.25) 0.80 x 9.63 (0.05) 6.64 n 1.60 (0.13) 1.10 ¼ 2.94 (0.17) 2.00 0.95 (0.01) -0.96 (0.01) 1.00 - 0.69 (0.11) 0.98 (0.01) 0.73 (0.13) 0.08 (0.04) 0.04 (0.05) ½ (n; variable) Union Modelii variable ¾?variable ¾? variable ¾? ytot ? ½ (ytot ; variable) ? ½ (n; variable) Our Modeliii variable ¾?variable ¾? variable ¾? ytot ? ½ (ytot ; variable) ½? (n; variable) Table 2. In the table ytot represents aggregate output, ym market output, and yu underground output; c denotes total consumption, x aggregate investment, n market employment, and ¼ average labor productivity. Finally, ½(variabile; ytot ) represents correlation between ytot and variable, ½(n; variabile) correlation between n and variable, and ¾ variable denotes standard deviation of variable. Number is parenthesis represent the small sample standard deviations. The summary statistics are generated by one-hundred simulations, and the series are of length 104 quarters. References: (i) see Hansen (1985) e Chiarini e Piselli (2000), for (ii) see Chiarini and Piselli (2000); …nally, (iii) is the model presented in this paper. 6 Table 3: A Better Amplification Mechanism Parameters Indivisible Labori High Substitutionii Cho and Cooleyiii Home Productioniv Our Modelv q 1:00 3:00 1:00 1:00 1.00 ® 0:36 0:36 0:36 0:29 0.36 ¯ 0:984 0:984 0:990 0:989 0.984 ± 0:025 0:025 0:025 0:023 0.025 ½ 0:979 0:989 0:950 0:950 0.900 ¾ 0:0072 0:0012 0:0102 0:0070 0.0032 ¾shock 0.002469 0.000131 0.002081 0.000980 0.000102 Table 3. Parameter q denotes relative risk aversion parameter, ® capital share in a Cobb-Douglas production function, ¯ the subjective discount factor, ½ and ¾ the autocorrelation coe¢cient and the standard deviation of innovation process, respectively. Finally, ¾shock denotes variance of the stochastic shocks, and it is computed as ¾ shock = ¾=(1 ¡ ½). References (i): Hansen (1985), (ii): Burnside, Eichenbaum and Rebelo (1995). (iii): Cho and Cooley (1994). (iv): Greenwood, Rogerson and Wright (1995). (v) Model presented in this paper. Note that, even if we have more than one stochastic shock, ¾ are the same. 7