Shocking Regions: Estimating the Temporal and Spatial Effects of One-Time Events Michael Beenstock Daniel Felsenstein Hebrew University of Jerusalem The Issues • Rising interest in the spatial dynamics of shocks and disasters (Katrina, Tsunami, acts of warfare and terrorism). • Shocks have a spatial and temporal impact: onetime effect and cumulative effects • Much interest in the temporal effects: can cities bounce back? how long does it take? is there a size threshold for shocks? 2 The Methods • Control groups and trend analysis (Bram et al 2002, WTC 9/11). • Expanded I-O models (SIM) (Okuyama, Hewings and Sonis 2004, Kobe earthquake 1995) • CGE models (Rose et al 2004, electricity losses from Tennesse earthquake) • NEG models- path dependence and temporary equilibria (Brakman et al 2004, Davis and Weinstein 2002, wars and bombing damage: Hiroshima, Dresden) What about abrupt socio-econ processes and not just natural and man-made ‘disasters’? 3 The State of the Literature • Spatial Panel Models: Pfeifer & Deutsch (1980), univariate context temporal lags, ‘lagged’ spatial lags • Static Spatial Panel Models: Elhorst (2003) SAC and spatial lags Elhorst (2004) SAC and TAC 4 The State of the Literature (cont.) • Dynamic Spatial Panel Models – 2 stage process 1. spatial filtering 2. estimate dynamic panel Badinger, Muller and Tondl (2004) • Dynamic Spatial Panel Models – joint estimation, multivariate Spatial lags and spatial (auto)correlation estimated jointly with temporal lags and temporal autocorrelation. Beenstock and Felsenstein (2007) 5 The Questions • Method: can temporal and spatial dynamics of shocks be integrated (using spatial panel data)? • Temporary or permanent effects: What are the impulse responses? How long do they last? • Spatial issues: are shocks independent or spatially correlated? 6 Notation Regions: n = 1, 2, ….., N Time Periods: t = 1, 2, ..…, T Endogenous Variables (Yk) k = 1, 2, ..…, K Exogenous Variables (XP) p = 1, 2, ..…, P Temporal Lag (Yt-q) q = 1, 2, ..…, Q 7 Integrating Temporal and Spatial Dynamics in Spatial Panel Data • Cross Section (Spatial lag): ~ Yn X n Yn u n N ~ Yn w ns Ys sn W ( N N ) 0 wsn wns 0 • Time Series (Temporal lag): Yt X t Yt 1 ut 8 Identification Problem • In Cross Section (CS): ~ E(Ynun ) 0 Provided β = 0 Identification problem ML IV • In Time Series (TS): VARs under-identify the structural parameters. • SpVAR (CS + TS): Structural identification remains a problem. 9 Temporal and Spatial Dynamics (‘Lagged’ spatial lag) ~ ~ Ynt X nt Ynt Ynt 1 Ynt 1 unt Notation: – spatial lag – temporal lag – lagged spatial lag Error Structure: unt u~nt unt 1 u~nt 1 nt 1 E ( ) 2 sn – spatial autocorrelation (SAC) – lagged SAC (LSAC) – temporal autocorrelation (TAC) nr – spatial correlation (SC = SUR) ns 1 10 Weak Exogeneity (K=1) ~ ~ Ynt Ynt Ynt 1 Ynt 1 unt ~ Are Ynt-1 and Ynt 1 instruments for ? unt u~nt unt1 u~nt1 nt ~ 1. = = 0 Ynt-1 Ynt 1 weakly exogenous 2. = = 0 Ynt-1 Y~ weakly exogenous nt 1 3. = θ = 0 unt-1 Ynt-1 u~nt1 ~ Ynt 1 unt 11 The SpVAR Model ~ ~ Yknt kn kiYint kiYint 1 kiYint kiYint 1 knt i 1 K In Matrix Form: ~ *~ Yt A Yt B Yt 1 Yt Yt 1 t * * * where: • ’s are region specific effects, • δ’s are temporal lag coefficients • ’s are spatial lag coefficients • ’s are lagged spatial lag coefficients ~ Yt 0 1Yt 1 2Yt 1 et When = = 0, this equation reverts to an SVAR. 12 Data Sources • 9 regions, 1987-2004 • 4 variables: Earnings: Household Income Surveys (CBS) Population: Central Bureau of Statistics House Prices: Central Bureau of Statistics Housing Stock: Housing Completions (CBS) 13 Spatial Weights Asymmetric spatial weights based on distance and population size wknit Z it 1 d ni Z nt Z it where: dni = distance between regions n and i, Z= variable that captures scale effects. 14 Data Housing Stock (th sq m) Real Earnings (1991 prices) 30000 4500 25000 4000 20000 3500 15000 3000 10000 2500 5000 2000 0 1500 Kray ot Jerusalem Tel-Av iv Haif a Dan 03 02 01 00 99 98 04 20 20 20 20 20 19 19 96 95 94 97 19 19 19 19 92 91 90 93 19 19 19 19 89 88 87 North 19 19 19 03 South Sharon 04 20 02 20 01 20 00 20 98 97 96 95 99 20 19 19 19 19 94 19 93 19 92 19 91 19 90 19 89 19 88 19 19 19 87 Center Kray ot Jerusalem Tel-Av iv Haif a Dan Center 04 20 03 20 01 00 99 98 97 02 20 20 20 19 19 19 96 19 95 19 94 19 93 19 92 19 91 19 89 90 19 19 19 88 South Sharon North 15 Population (th) 1200 490 440 1000 390 800 340 600 290 240 400 190 200 140 0 90 20 04 20 03 20 02 20 01 20 00 19 99 19 98 19 97 19 96 19 95 19 94 19 93 19 92 19 91 19 90 19 89 19 88 19 87 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Kray ot Jerusalem Tel-Av iv Haif a Dan Center 03 02 01 00 99 98 97 96 95 94 93 92 91 90 04 20 20 20 20 20 19 19 19 19 19 19 19 19 19 89 South 19 88 House Prices (1991 prices) 19 19 Data (cont.) Sharon North 16 Panel Unit Root Tests Ln(Yj) d=0 d=1 d=2 Earnings -1.205 -3.503 -5.079 Population -2.707 -2.531 -6.603 House Prices -3.030 -2.537 -5.321 Housing Stock -0.092 -2.227 -3.410 • Auxiliary regression: dlnYknt = kn + knd-1lnYknt-1 + kndlnYknt-1 + knt. • Critical values of t-bar with N = 9 and T = 18 are –2.28 at p = 0.01 and –2.17 at p = 0.05. • We estimate SpVAR in log first differences 17 Estimating the SpVAR Earnings Population House Prices Housing Stock Temporal Lag(δ) Unrestricted Restricted Unrestricted Restricted Unrestricted Restricted Unrestricted Restricted Model Model Model Model Model Model Model Model -0.357 Earnings -0.311* Population -0.148 House Prices 0.970 Housing Stock Lagged Spatial Lag (λ) 0.131** Earnings -0.314** Population 0.205** House Prices 1.836 Housing Stock 0.146 R2 adjusted 2.235 Panel DW F statistic SBC unrestricted SBC restricted -0.332 -0.104 1.019 0.038 0.112** 0.0004** -0.078** 0.037 - 0.104 0.678 -0.006** 0.0003 -0.497 0.196** 2.174 0.148 2.176 0.847 0.018** 0.037** 0.104 -0.359 0.297 2.116 0.103 -0.458 0.312 1.866 0.393 0.233 -0.593* 0.493 -0.790 0.091 1.843 0.102 0.672 - 0.006** 0.059 0.016 0.396 0.060 0.018 0.389 0.235 0.0003** -0.605* -0.064 -0.068 0.403 0.003** -0.810 0.172 0.170 0.107 0.464 0.474 1.861 1.641 1.639 0.000 0.019 -814.88 -818.97 18 Spatial Lag and Spatial Autocorrelation Coefficients Earnings Population House Prices Housing Stock -0.426* -0.0100 -0.0984 -0.0215* TAC -0.147* -0.034** 0.0094** 0.0443** SAC 0.794 0.836 0.853 0.952 LSAC 0.118** -.0400** -0.0066** -0.0602** (Determinant of correlation matrix) 0.0049 0.0003 0.000091 0.0014 Spatial Lag () Error Parameters *Coefficients significant at 0.05<p<0.1 ** Coefficients significant at p>0.1 19 Spatial Correlation (SC): SUR Estimates Jerusalem Tel Aviv Earnings Population Housing Prices Haifa Earnings Population Housing Prices Krayot Earnings Population Housing Prices Dan Earnings Population Housing Prices Center Earnings Population Housing Prices South Earnings Population Housing Prices Sharon Earnings Population Housing Prices North Earnings Population Housing Prices Tel Aviv Haifa Krayot Dan Center South Sharon 0.4689 0.0592 0.4681 0.8367 0.5258 0.6395 0.4465 0.5760 0.4885 0.3769 0.1443 0.7259 0.3261 0.3571 0.3628 0.1686 -0.0986 0.7532 -0.0947 0.1560 0.3123 0.6699 0.7005 0.4088 0.4624 0.4381 0.1188 0.9057 0.6346 0.7662 0.2435 0.8092 0.2150 0.6846 0.0275 0.7621 -0.1596 0.6268 -0.0042 0.3445 0.6940 0.3192 0.5693 0.4371 0.7720 0.4450 0.5025 0.3631 0.4029 0.6501 0.5410 0.2653 -0.0672 0.6314 0.6675 0.1329 0.7591 0.3945 0.4096 0.4384 0.3180 0.2908 -0.3851 0.3490 0.6475 0.2860 -0.2398 0.1425 0.5510 0.2584 -0.4762 0.2024 0.1060 0.5066 -0.2845 0.1480 0.3680 0.2959 -0.4985 0.4834 0.5494 0.2491 -0.4704 0.4808 0.1975 0.3651 -0.1399 0.6307 0.0748 0.6995 0.1156 0.5167 0.2110 0.7510 0.2709 0.6013 0.1117 0.7970 0.4803 0.4715 0.0491 0.7944 0.3213 0.7682 0.2969 0.4116 0.5398 0.5781 0.6222 0.3496 -0.2150 0.3371 0.4529 0.6555 0.6104 0.1364 0.2913 0.4359 0.5999 -0.0331 0.3333 0.8813 0.4791 0.3159 0.1053 0.7927 0.4058 0.5648 0.2991 0.6439 -0.0860 0.1499 0.4946 0.5445 0.5896 -0.1297 0.2078 0.5638 -0.2150 0.1607 0.2438 0.7686 0.0463 0.1653 20 SpVAR Impulse Response Simulations: The effect of shocks to variable k in region n on: • The shocked variable in the region in which the shock occurred • Other variables in which the shock occurred • The shocked variable in other regions • Other variables in other regions 21 Simulated Impulse Responses: 2% Earnings Shock in Jerusalem W age Price 2.5% 2.0% J erus alem Sout h 1.5% 0.01% 0.25% 0.00% 0.20% 0.00% D an 1.0% 0.08% J erus alem 0.07% Sout h 0.06% D an 0.15% 0.00% 0.05% 0.04% 0.10% 0.5% 0.00% 0.0% 0.00% 0.03% 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 0.05% 0.01% 0.00% 0.00% -1.0% 0.00% -0.05% 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 -0.5% Populat ion 0.01% J erus alem 0.01% Sout h D an 0.00% 0.00% 0.0% 0.00% 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 0.0% 0.00% 0.0% 0.00% 0.0% 0.00% 0.009% -0.01% 0.001% 0.008% J erus alem 0.001% 0.007% Sout h 0.001% 0.006% D an 0.005% 0.004% 0.003% 0.001% 0.000% 0.000% 0.002% 0.000% 0.001% 0.000% 0.000% 0.000% 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 0.0% 0.00% Area 0.1% 0.1% 0.02% 22 Simulated Impulse Responses: 2% Population Shock in Tel Aviv W age Populat ion 0.4% 0.08% 2.5% 0.2% 0.06% 2.0% 0.0% 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 0.04% -0.2% 0.02% Tel-Av iv D an Kray ot 1.5% 0.01% 0.02% -0.4% 0.01% 1.0% 0.00% -0.6% -0.02% D an -1.0% Kray ot -1.2% -0.04% 0.0% -0.06% -0.5% -0.01% 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 Tel-Av iv -0.8% 0.00% 0.5% Price Area 1.60% 1.40% 0.05% 0.140% 0.00% 0.120% 1.20% -0.05% 0.60% Tel-Av iv D an Kray ot 0.40% 0.20% -0.10% 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 -0.40% Tel-Av iv -0.005% D an Kray ot -0.010% 0.080% -0.015% 0.060% -0.15% -0.020% 0.040% -0.20% 0.00% -0.20% 0.100% 0.000% 0.020% -0.25% 0.000% -0.30% -0.020% 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 1.00% 0.80% -0.01% -0.025% -0.030% -0.035% 23 Impulses 1991 With and Without SC (a) 2% Earnings Shock in Jerusalem (a) Jerusalem Dan South Earnings -0.00664 -0.00664 -0.00307 0.00000 -0.00211 0.00000 Population 0.00073 0.00073 0.00043 0.00000 0.00023 0.00000 Prices 0.00421 0.00203 0.00370 0.00021 0.00328 0.00071 Housing Stock 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 Prices 0.01968 0.01345 -0.00801 -0.00272 0.00083 -0.00078 Housing Stock 0.00155 0.00119 -0.00053 -0.00031 0.00004 -0.00008 (b) 2% Population Shock in Tel Aviv (b) Tel Aviv Dan Krayot Earnings -0.00994 -0.00993 0.00630 0.00000 -0.00098 0.00000 Population 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 24 Main Results • Evidence of temporal lags, spatially autocorrelated errors and ‘lagged’ spatial lags. • Impulses: reverberate across space and time, feedback effects. But die out quite quickly • Impulse response across regions: dictated by spatial weighting system, eg Jerusalem has greater spillover effect on South than on Dan region • Spillover effects from Tel Aviv: reflects spatial lag coefficients in magnitude and sign 25 Conclusions • Integration of time series and spatial econometrics • Joint estimation in SpVAR (not 2-stage estimation) • Difference between spatially correlated errors (SC) and spatially autocorrelated errors (SAC) and lagged SAC • Impulse responses – ripple-through effect within and between regions 26