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Behavioural Finance Lecture 12 Part 2 The Global Financial Crisis Empirical Data & Modelling Modelling financial instability • Financial Instability Hypothesis only theory that makes sense of this data • Model in previous lecture – Had only “implicit” money – Omitted Ponzi Finance – Omitted role of deflation • This lecture – Model with Ponzi finance – Combining Minsky and the Circuit • Full monetary model of capitalism Modelling financial instability • Firstly: last week’s Goodwin model in equations K • Causal chain: capital determines output Y • Output determines employment v Y L a • Employment rate determines rate of change of wage (Phillips curve PH) 1 d L PH w w dt N • Wages (w.L) determine profit P Y w L P • Profit P determines investment = rate of change of capital I P K d K dt 1d 1 d • Population growth & technical change a ; N a dt N dt drive the system: Modelling financial instability • System has 4 “differential equations”: • Some calculus needed to work out other terms: d Y g Y dt d Wage level: w PH w dt d Productivity: a a dt d Population: N N dt Growth rate: I r 1 d 1 d K 1 d 1 g Y K I r Y K K dt v K dt Y dt K v v • Full system is… Modelling financial instability • 4 differential equations & 7 algebraic relations System States Algebraic Relations d Y( t) dt g ( t) Y( t) Y( 0) Y0 P( t) Y( t) W ( t) P( 0) P0 d w ( t) dt PH( ( t) ) w ( t) w ( 0) w0 W ( t) w ( t) L( t) W ( 0) W0 d a( t ) dt d N ( t) dt a( t) N ( t) a( 0) N ( 0) a0 N0 L( t) ( t) ( t ) r( t) Y( t) a( t ) L( t) N ( t) w ( t) a( t ) P( t) v Y( t) I r( t) g ( t) v L( 0) L0 ( 0) 0 ( 0) 0 r( 0) g ( 0) r0 g0 • Simulating this, gives same cyclical pattern as last week’s “systems engineering” model Modelling financial instability • Cyclical growth… Output • Limit Cycles cycle in wages & employment in employment and wages 6000 110 4000 90 80 2000 70 0 Employment Rate % Wages share % 0 20 40 60 80 100 Income & Employment Limit Cycle 0 20 40 60 80 Years • Then add in debt… 1 0.9 0.8 0.7 0.6 0.8 60 Year 1.1 Wages Share of Output Real output 100 0.85 0.9 0.95 Employment Rate 1 1.05 100 Modelling financial instability • Firms borrow when desired investment exceeds profits: Change in debt: d D I P dt • Profit now net of interest payments P Y W r D D • A new system state: debt to GDP ratio d Y • Very different dynamics but stable system 110 Employment vs wages share 110 100 Wages share % 100 90 80 80 70 70 60 90 60 80 0 20 40 60 80 85 90 95 100 Employment Rate % Employment % Wages share % 100 105 Modelling financial instability • Now add in Ponzi Finance – Borrowing $ to speculate on rising asset prices – Adds to debt without adding to productive capital • Modelled as a function of rate of economic growth – Higher rate of growth, higher level of speculation Ponzi Finance: 1 d P g Y dt • Aggregate debt now includes Ponzi Finance d Change in debt: D I P P dt Modelling financial instability • Now a six-dimensional model: System States Algebraic Relations d Y( t) dt g ( t) Y( t) Y( 0) Y0 P( t) Y( t) W ( t) r( t) ( D( t) ) d w ( t) dt PH( ( t) ) w ( t) w ( 0) w0 W ( t) w ( t) ( L( t) ) d a( t ) dt d N ( t) dt d D( t) dt d P( t) dt a( t) a( 0) N ( t) I r( t) Y( t) P( t) P( t) Ponzi ( g ( t) ) Y( t) N ( 0) D( 0) P( 0) a0 N0 D0 P0 L( t) ( t) ( t ) r( t) g( t) Y( t) a( t ) L( t) N ( t) W ( t) Y( t) P( t) v Y( t) I r( t) v d( t) • Very different dynamics… Y( t) • With Ponzi switch set to zero, same as before • With Ponzi “on”… P( 0) P0 W ( 0) W0 L( 0) L0 ( 0) 0 ( 0) 0 r( 0) r0 g ( 0) g0 d ( 0) d0 D( t) Modelling financial instability • Dynamics – Borrow money to finance investment during a boom • Repay some of it during a slump – Debt/ Income ratio rises in series of booms/busts – Eventually one boom where debt accumulation passes “point of no return”… Employment Rate Real Output 1500 No Speculation Ponzi Finance 100 Per cent 1000 90 500 80 No Speculation Ponzi Finance 70 0 0 10 20 30 40 0 10 20 30 50 Years 40 50 Modelling financial instability • Driving force is debt to GDP ratio… Debt to GDP Ratio 1200 No Speculation (LHS) Ponzi Finance (RHS) Per cent of GDP 0 1000 20 800 40 600 60 400 80 200 100 120 0 0 10 20 30 40 200 50 Per cent of GDP 20 Are We “It” Yet? • Can summarise model’s equations in 4 “stylised facts” – Employment rises if growth exceeds productivity + population increase – Wages share grows if wage rises exceed productivity – Bank lend money to finance investment & speculation – Speculation rises when growth rises • Same model in flowchart form (with different parameters)… Are We “It” Yet? + • Minsky: Ponzi finance extension to Keen 1995 Investment Capital Output Plot Speculative to Productive Debt Output 6 5 Cyclical Growth 2000 4 1000 3 2 0 0 10 20 30 40 50 Time (Years) 60 70 1 0 WageShare Click here to download Vissim viewer program Output 0 10 30 40 Time (Years) 50 60 70 Cyclical Growth Debt Ratios Wages share of output Employment Rate 1.0 .5 0 On DebtInModel On Off Ponzi InitialBoom Plot Debt to Output Ratios 0 10 20 30 40 50 Time (Years) 60 70 6 Total Debt Productive Speculative 5 Cyclical Growth 4 1.1 Employment • Click on icon to run simulation after installing Vissim Viewer 20 3 .9 2 .7 1 .5 .3 .5 EmploymentRate + Profit + .7 .9 Wages * 1.1 Employment InterestRate TotalDebt 0 0 10 + + 20 30 40 Time (Years) Productive Debt Speculative Debt 50 60 Profit Investment RateOfGrowth 70 Are We “It” Yet? • Weakness of previous model – Implicit money only—deflationary process ignored – No explicit treatment of aggregate demand • Overcome by blending Minsky with the Circuit – Lay out basic macro operations in accounts table • See “Roving Cavaliers of Credit” for basic approach • Also “Circuit Theory & Post Keynesian Economics” – Generate financial flows dynamics – Couple with Goodwin cycle model Are We “It” Yet? • The financial flows table: "Type" 0 0 1 1 1 "Account" "Bank Capital" "Bank P/L (B.PL)" "Firm Loan (FL)" "Firm Deposit (FD)" "Worker Deposit (WD)" "Symbol" B.C( t) B.PL( t) F.L( t) F.D( t) W .D( t) "Compound Debt" 0 0 A 0 0 "Pay Debt" 0 B 0 B 0 "Record Payment" 0 0 B 0 0 "Debt-financed Investment" 0 0 C C 0 M.1 "Wages" 0 0 0 D D "Interest" 0 ( E F) 0 E F "Consumption" 0 G 0 G H H "Debt repayment" I 0 0 I 0 0 0 I 0 0 "Record repayment" "Lend from capital" J 0 0 J 0 "Record Loan" 0 0 J 0 0 • Nonlinear functions for placemarkers C, I and J: C Inv r( t) PC( t) Yr( t ) I J FL( t) RL r( t) BC( t) LC r( t) Are We “It” Yet? • Fully specified Phillips function for wage setting: – Employment – Rate of change of employment – Rate of inflation adjustments d W ( t) dt Phillips 1 Inv r( t) 1 W ( t) W ( ( t) ) Ph( ( t) ) Rate of v change ofemployment ( ) 1 Inflation v v Pc a( t) ( 1 s ) PC( t) Curve Wages and Employment Rate Percent change in money wages 20 15 100 Ph 100 10 5 0 5 90 92 94 96 Employment Rate 98 100 Are We “It” Yet? • Investment, debt repayment and money relending functions: Investment & Profit Rate Loan Repayment and Money relending 50 20 Loan repayment Money relending 40 100 100 Inv r 30 Years Percent of GDP 15 20 x LC 100 10 5 10 0 5 x 100 RL 0 5 r Profit Rate % 10 0 10 5 0 x Rate of Profit 5 10 Are We “It” Yet? Financial Sector • Overall model: 14 equations (11 ODEs, 3 algebraic) • 5 equations for financial sector • 1 for prices • 1 for wages • 7 for physical economy d BC( t) dt d BPL( t) dt FL( t) RL r( t) BC( t) LC r( t) rL FL( t) rD FD( t) rD W D( t ) BC( t) FL( t) BPL( t) B d FL( t) dt LC r( t) d FD( t) dt BC( t ) FL( t) BPL( t) W D( t ) W ( t) Yr( t) rD FD( t) rL FL( t) PC( t ) Yr( t) Inv r( t ) LC r( t ) RL r( t) B W a( t ) d W D( t) dt RL r( t ) PC( t) Yr( t ) Inv r( t) rD W D( t) W D( t) W W ( t) Yr( t ) a( t ) Physical output, labour and price systems Level of output Rate of Profit v Yr( t) PC( t) Yr( t ) W ( t) rL FL( t) a( t ) r( t ) Rate of employment v PC( t) Yr( t ) d ( t) dt Rate of real economic growth Rate of change of wages Kr( t) Yr( t ) g( t) d W ( t) dt 1 Inv r( t) ( t ) v ( ) v v Inv r( t) v 1 Inv r( t) 1 W ( t) W ( ( t) ) Ph ( ( t) ) v ( ) 1 v a( t ) ( 1 s ) PC( t) v Pc Rate of change of prices d PC( t ) dt Rate of change of capital stock d Kr( t ) dt Rates of growth of population and productivity d a( t ) dt 1 Pc PC( t) W ( t) a( t ) ( 1 s ) Kr( t) g ( t) a( t ) d N ( t) dt N ( t) Are We “It” Yet? • Same system in QED: Are We “It” Yet? • Integrating Minsky & the Circuit – Debt-deflationary dynamics in strictly monetary Minsky-Circuit model – “The Great Moderation”, then “The Great Crash” Bank Accounts Debt to Output Ratio 5 110 5 4 110 Years to repay debt 4 $ 1000 100 Bank Equity Bank Transactions Firm Loan Firm Deposit Worker Deposit 10 1 0 10 20 30 Year 40 3 2 1 0 50 0 10 20 30 Year 40 50 Are We “It” Yet? • Stability is destabilizing... Rate of employment and rate of profit Real growth rate 10 20 15 5 90 0 Percent p.a. 100 Percent p.a. Percent of workforce 110 5 100 ( ) 0 80 Employment Profit 70 10 0 10 5 20 30 5 50 40 0 10 20 30 40 50 Employment and wage share dynamics 120 Year Inflation Rate Percent p.a. 40 20 0 0 Worker share of GDP 60 100 80 60 20 40 40 0.7 0 10 20 30 40 50 0.8 0.9 Employment rate 1 1.1 Are We “It” Yet? • Income inequality – Not worker vs capitalist but worker vs banker Income Distribution 110 Workers Capitalists Bankers 100 90 Percent of GDP 80 70 60 50 40 30 20 10 0 10 0 10 20 30 Year 40 50 Are We “It” Yet? rl • Can government policy save us? • Simple model with fiat injection implies can succeed against credit crunch alone: Bank Assets 1500 Bank Liabilities (Deposits) Loans Unlent Reserves 1250 1500 1000 1000 750 750 500 500 250 250 0 0 10 20 Firms Households Banks 1250 30 Time (Years) 40 50 60 URate 0 0 10 InfRate 20 B_D H_D Unemployment 25 40 50 60 40 50 60 F_D Inflation No Stimulus Bank Injection Borrowers Injection 20 30 Time (Years) 10.0 7.5 No Stimulus Bank Injection Borrowers Injection 5.0 2.5 15 0 10 -2.5 -5.0 5 -7.5 0 0 10 20 30 Time (Years) 40 50 Parameters & Initial Conditions Financial System NoStimulus Production System StimBank 0 60 -10.0 0 10 20 3 Debt to Output Ratio Magnitude of Crunch 25 30 Time (Years) 25 No Stimulus Bank Injection Borrowers Injection 20 C_size tCC 15 StimFirm StimFirm F_L Y l r / 100 10 1. 5 D:0 S:1 60. 0 0 10 20 30 40 Time (Years) 50 60 Are We “It” Yet? • My expectation: best outcome of government policy alone will be Japanese Stalemate – Government monetary injections neutralise private sector deleveraging – Outcome “Turning Japanese”: • Long-term stagnation and borderline deflation • Need debt abolition & real financial reform – Cancel debts that should never have been issued – Cauterise financial sector in the process – Reform assets to minimise chance of future bubbles • Shares on secondary market expire in 30 years • Property leverage limited to 10 times annual rental