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EURACE and SPACE Christophe Deissenberg Université de la Méditerranée and GREQAM Bruxelles, Oct. 1st 2010 EURACE and SPACE 1 EURACE An agent--based software platform for European economic policy design with heterogeneous interacting agents: new insights from a bottom up approach to economic modeling and simulation IST-FET proactive initiative “Simulating Emergent Properties in Complex Systems” Bruxelles, Oct. 1st 2010 EURACE and SPACE 2 Bruxelles, Oct. 1st 2010 EURACE and SPACE 3 EURACE Goals 1. Technological: Construct a software platform to perform and analyze very-large-scale agent-based simulations on parallel computing systems. 2. Scientific: Develop a very large, closed agent-based model of a multi-national economy (EU-27). 3. Economic: Conduct and analyze macroeconomic policy experiments. Bruxelles, Oct. 1st 2010 EURACE and SPACE 4 EURACE Structure ROW: Energy Regulatory bodies Central bank regulations Firms financing labour reserves revenues taxes interests interests Governments Labour markets Cons. Goods markets Assets markets Banks taxes savings wages Bruxelles, Oct. 1st 2010 public spending goods Households EURACE and SPACE dividends, interests interests 5 Stock-flow consistency • Interlinked balance sheets: – Consistency of all stocks and flows – Monetary and physical flows – Time-evolution of the balance sheets • System of national accounts: – SAM: Social accounting matrix • Consistency rules: – Accounting identities (intra agent) – Economic time-invariants (across sectors) Bruxelles, Oct. 1st 2010 EURACE and SPACE 6 Time and space • Decisions are taken daily, monthly, quarterly, or annually • Likewise, beliefs are updated and data are processed daily, monthly, quarterly, and annually • Space is divided into heterogeneous regions (countries) • Production, sales, and housing occur at specific geographical locations • Transportation of goods and commuting are costly Bruxelles, Oct. 1st 2010 EURACE and SPACE 7 EURACE Agents • • • • • • • • Households (∼10⁶) Investment good producers (∼ 10²) Consumption good producers (∼ 10³) Local outlet malls (∼ 10) Banks (∼ 10²) Governments (∼ 27) Central Bank (1) Others: Market research entity, Statistical office (Eurostat), Asset Management Companies. Bruxelles, Oct. 1st 2010 EURACE and SPACE 8 Decision making • Behavioral rules: strong micro-foundations, empirically based : Firms: standard decision-making rules from the Operations Management/MBA/Finance literature: Markup pricing Standard Inventory and Production Planing etc. Households: saving and consumption decisions a la Deaton (1991). beliefs formation: History Local feedback: economic partners Global/regional feedback: Eurostat Bruxelles, Oct. 1st 2010 EURACE and SPACE 9 Details: Consumption Goods • Homogenous consumption goods are produced using (vertically differentiated) capital and labor. • Complementarity between quality of investment goods and level of specific skills of workers – Productivity of a given technology level is only fully exploited if workers in the firm have sufficiently high specific skills. • Differentiated skill structure: general (formal training), specific – General skills heterogeneous within and across regions. – Specific skills attained during employment in firms. – Higher general skills improve speed of attaining specific skills. Bruxelles, Oct. 1st 2010 EURACE and SPACE 10 Details: CGs Market • Consumption goods producers offer (and store) goods at selected geographically distributed local market outlets (‚malls‘). They post (different) prices of their goods in all malls they serve. • When visiting a mall a consumer collects randomly selected information about local prices and inventories. Purchasing decision is modelled using a logit approach. • Suppliers on the consumption goods market act globally (without spatial frictions) whereas consumers buy locally. Bruxelles, Oct. 1st 2010 EURACE and SPACE 11 Details: Technological Change • The quality of supplied investment goods increases stochastically over time. • The average quality of the capital stock of a CGP is updated as old capital is replaced by new investments. • The profits of investment goods producers are uniformly distributed to households. Bruxelles, Oct. 1st 2010 EURACE and SPACE 12 Details: Labor market • Firms post job vacancies based on planned output. • Searching workers send applications based on posted salaries. • Firms rank applications based on general skills and make offers. • Workers rank offers (wage - commuting costs), compare best offer to their reservation wage and accept/reject. • => Firms may be rationed on the labor market; there is frictional unemployment. • => Labor Market is global with spatial frictions Bruxelles, Oct. 1st 2010 EURACE and SPACE 13 Using EURACE: Philosophy Calibrate the parameters, using empirical data wherever possible. • Some parameters are chosen in order to stabilize the simulations and yield plausible outcomes: – Examples: • Parameters in demand forecasting rules • Parameter governing wage offer increases triggered by rationing on the labor market • Speed of adjustment of firm’s planned capital stock • Parameters in the consumer’s logit model Bruxelles, Oct. 1st 2010 EURACE and SPACE 14 Using EURACE: Philosophy Check that EURACE model is able to reproduce the main ‘stylized facts’: time series and distributions. Run simulation batches for different policy scenarios. Formulate hypotheses about the policy impact. Use statistical tests to check the significance of the hypothesized impact. Gain a qualitative understanding of the relevant economic mechanisms responsible for the observed phenomena by examining the evolution of key variables. Bruxelles, Oct. 1st 2010 EURACE and SPACE 15 Using EURACE: Practice • EURACE is implemented in FLAME • EURACE can run on any machine, from a PC (practically: up to about 10 000 agents) to massively parallel machines • A GUI allows straightforward modifications of the behavioral rules, initialization, running of simulations, storage and statistical analysis of the desired parts of the output, production of graphics, etc. Bruxelles, Oct. 1st 2010 EURACE and SPACE 16 Some policy experiments • • • • • • Open labor markets within the EU: Frictions can be Pareto-improving. Should a government invest in formal education or subsidize the firms? The effects of quantitative easing and fiscal tightening in dealing with a credit crisis. A comparative study of policies to deal with an exogenous oil price shock. The importance of financial management rules. Etc. Bruxelles, Oct. 1st 2010 EURACE and SPACE 17 EURACE: Some conclusions • The agent-based EURACE macro-model reproduces well major stylized facts, some of which are not adequately captured by the standard models. • It has been used to explore several issues directly relevant to the Lisbon strategy or to European policy-making in general. • It allows to capture important aspects of the heterogeneity between EU members. • The results of policy experiments confirm sometimes the conventional wisdom. In other instances, they are new, unexpected, but meaningful. • For example, EURACE shows that the link between demand effects and diffusion of new technologies matters (although it is ignored in standard new growth models) • Reasonable “micro-explanations“ were found for all the results. Bruxelles, Oct. 1st 2010 EURACE and SPACE 18 EURACE: Some conclusions All this makes us confident that the concept underlying EURACE is sound and can shed new, policy-relevant light on the working of a multinational economy But much remains to do … A next step: SPACE ? Bruxelles, Oct. 1st 2010 EURACE and SPACE 19 SPACE • A FET-Open proposal, with main goals: 1. Develop a comprehensive, empirically meaningful, modelling framework that allows to study the complex interactions in a spatial multinational economy; 2. Develop the ICT technology that makes the model practically useful for policy making Bruxelles, Oct. 1st 2010 EURACE and SPACE 20 SPACE • Like EURACE, we shall develop a very large, empirically meaningful, multi-scale agent-based model of a multi-national economy • But SPACE will be MUCH MORE advanced, among others w.r.t. to the physical and non-physical evolving networks linking the agents • It will include among others realistic financial networks (financial institutions and firms), allowing more in-depth investigations of financial (in)stability and of the link financial-real sphere • It will allow to study country-city dynamics, the spatial aspects of knowledge flow … Bruxelles, Oct. 1st 2010 EURACE and SPACE 21 SPACE • The agents will interact on evolving networks (trade, communication, etc.) • They will be able to relocate on the landscape • They will exhibit adaptive behavior based on past experience. • Some other important features that the model will capture are demographic aspects (population aging, births and deaths) as well as sophisticated protocols for firm creation and bankruptcy • SPACE will have the potential to be linked to major existing spatial models capturing e.g. environmental issues, climate change, epidemics, or other dynamic properties of the physical environment . Bruxelles, Oct. 1st 2010 EURACE and SPACE 22 SPACE The needs of the decision-makers will be better taken into account: • Better interface • Improved data management • Innovative vizualisation techniques • Computational steering • Etc. Bruxelles, Oct. 1st 2010 EURACE and SPACE 23 SPACE The development philosophy will be different: • EURACE: Develop more or less independent modules and integrate them ex-post • SPACE: Define a complete skeleton and enrich it organically Bruxelles, Oct. 1st 2010 EURACE and SPACE 24 SPACE SPACE will make qualitative and quantitative quantum leaps towards offering a comprehensive, practicable agent-based model for multi-national policy-making Bruxelles, Oct. 1st 2010 EURACE and SPACE 25 Thanks for your attention! Bruxelles, Oct. 1st 2010 EURACE and SPACE 26 EURACE Agents • Households Buyers on Consumption Goods Market Sellers on Labor Market Deposits at banks Buyers/Sellers of firm shares • Consumption Goods Producers Buyers on Labor and Investment Goods Markets Sellers on Consumption Goods Markets Loans from banks Bruxelles, Oct. 1st 2010 EURACE and SPACE 27 EURACE Agents • Commercial Banks Collect deposits from Households Give loans to firms Access standing facilities of the central bank • Government Collects taxes, distributes unemployment benefits, subsidies Bruxelles, Oct. 1st 2010 EURACE and SPACE 28 EURACE Agents • Eurostat Collects regional and sector data Constructs macrodata • Central Bank Monetary policy • Malls Local markets for consumers, global markets for firms • Clearinghouse Implements the order matching market mechanism for asset orders Bruxelles, Oct. 1st 2010 EURACE and SPACE 29