2. METODOLOGÍA
3.1. Resultados
3.1.2. Casos de estudio en red de prueba IEEE New England 39-bus 105
Employment: We use data provided by a working committee of employment statistics (Erwerbstätigenrechnung des Bundes und der Länder). This dataset contains annual average values of the employees at the state level for the years 1970-2005. Freelancers are included.
Government revenues and expenditures: We use data from the German Federal Statistic Office (Statistisches Bundesamt) which contain information about the aggregated
government revenues and expenditures at the state level. Data for the West German states are available since 1985, for the East German states since 1992.
Industry diversification: Herfindahl index computed for the number of workers in 15 industrial sectors. We calculate this index as:
2
DIV ERW , where is the industry diversification of state i in year t,
is the number of employees in state i, in sector j in year t, is the number of employees in state i in year t, n is the total number of employees in state i in year t.
Sectoral employment data are obtained from a working committee of employment
statistics (Arbeitskreis Erwerbstätigenrechnung des Bundes und der Länder) for the years 1991-2004.
Long-term unemployment rate: The data are taken from the German Working Agency (Bundesagentur für Arbeit). Long-term unemployed are persons who are unemployed more than one year. We use the data from 1977-2003.
Openness: State-level exports and imports relative to state GDP. The data are taken from the German Federal Statistic Office (Statistisches Bundesamt)
Output: Data we use are taken from the German Federal Statistic Office (Statistisches Bundesamt). We use the price-adjusted GDP growth at state level, for the West German States since 1971, for the East German states since 1991.
Service sector: We use sectoral data from from a working committee of employment statistics (Arbeitskreis Erwerbstätigenrechnung des Bundes und der Länder) for the years 1970-2004 to compute the share of employees in the service sector
Unionization: Data on the share of employees organized in German unions are taken from the German employees association (Deutscher Gewerkschaftsbund).
Graph 1: Employment Volatility by German State
This Graph plots the volatility of regional employment growth for the West German states. Employment growth is the year-to-year cyclical change in the level of employment. The cyclical component is obtained using the Hodrick-Prescott-Filter. Volatility is the standard deviation of employment growth over a 5-year moving window. We show the unconditional volatility of employment growth and the conditional volatility of employment growth based on the residual of a regression of employment growth on time fixed effects and five lags of the dependent variable.
0.511.50.511.50.511.5
1970 1980 1990 2000 2010 1970 1980 1990 2000 2010
1970 1980 1990 2000 2010 1970 1980 1990 2000 2010
Baden-Württemberg Bayern Bremen Hamburg
Hessen Niedersachsen Nordrhein-Westfalen Rheinland-Pfalz
Saarland Schleswig-Holstein
Employment volatility (uncond) Employment volatility (cond)
percent
year
Graphs by bula
Source: German Statistical Office, authors’ calculations.
Graph 2: Trade Openness by German State
Trade openness is the sum of state-level imports and exports over state-level GDP.
0.510.510.510.51
1970 1980 1990 2000 2010 1970 1980 1990 2000 2010 1970 1980 1990 2000 2010 1970 1980 1990 2000 2010
Baden-Württemberg Bayern Berlin Brandenburg
Bremen Hamburg Hessen Mecklenburg-Vorpommern
Niedersachsen Nordrhein-Westfalen Rheinland-Pfalz Saarland
Sachsen Sachsen-Anhalt Schleswig-Holstein Thüringen
Trade openness Import openness
Export openness
percent
year
Graphs by bula
Source: German Statistical Office, authors’ calculations.
Table 1: Descriptive Statistics
See the Data Appendix for a detailed description of these variables. ‘Volatility’ is the standard deviation of the growth rate of the respective variables over a five-year rolling window.
Variable Observations Mean Std. Dev. Min Max
Degree of industrial diversification 240 0.113 0.013 0.094 0.170 Export openness (%) 455 0.200 0.088 0.040 0.500 Import openness (%) 454 0.216 0.138 0.040 0.690 Long-term unemployment rate (%) 330 0.289 0.073 0.129 0.377 Service sector (%) 450 0.631 0.096 0.378 0.855 Trade openness (%) 434 0.427 0.199 0.083 1.049
Unionization (%) 450 0.282 0.044 0.198 0.336
Volatility of employment growth (%, conditional) 290 0.345 0.169 0.081 0.969 Volatility of employment growth (%, unconditional) 370 0.925 0.497 0.160 4.176 Volatility of nominal government expenditures (%) 214 2.914 1.440 0.302 6.389 Volatility of nominal government revenues (%) 214 3.883 2.358 0.517 12.611 Volatility of real output growth (%) 370 1.568 0.646 0.120 3.420
Table 2: Determinants of Regional Employment Volatility
This Table presents results of fixed effects panel estimators. t-values based on robust standard errors clustered at the state-level are reported in brackets. The full sample includes information for 16 German states, the West German sample includes information for 10 West German states (excluding Berlin). Data are for the years 1971-2005. The dependent variable is the volatility of employment, calculated as the squared growth rate of employment. ‘Unconditional’ is the unadjusted employment growth, ‘conditional’ are the squared residuals of a regression of the growth rate of employment on up to five own lags, year fixed effects, and a unification dummy. The conditional and unconditional volatility of output growth and government spending and revenue are computed analogously. See the Data Appendix for details on the specifications of the variables. ***, **, * = significant at the 1%, 5%, 10% level.
a) Full sample
Unconditional employment volatility Conditional employment volatility (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) Volatility of output growth 0.205** 0.206** 0.209** 0.240** 0.370*** 0.199** 0.168** 0.056*** 0.057*** 0.058***
(2.70) (2.75) (2.78) (2.80) (2.95) (2.92) (2.94) (3.43) (3.33) (3.88) Trade openness 0.486 3.150 3.477 -2.173 -0.159 0.276
(0.13) (0.74) (0.33) (0.68) (0.10) (1.13)
Import openness -1.726 -0.167
(0.47) (1.38)
Export openness 4.525 1.047*
(0.71) (1.83)
Volatility of government revenue -0.006
(1.12)
Volatility of government spending 0.005
(0.62)
Industry diversification -171.245
(1.44)
Unemployment -23.789
(1.55)
Service sector -32.501***
(3.12)
Long-term unemployment rate 0.331
(0.20)
Table 2a continues …
Table 2a continued …
Unconditional employment volatility Conditional employment volatility (1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
Degree of unionization 6.661
(1.40)
Reunification dummy 0/1 0.187 0.205 0.189 0.315 3.437 0.026 1.023** -0.052 -0.064 -0.043 (0.38) (0.41) (0.36) (0.67) (1.37) (0.04) (2.61) (1.27) (1.44) (1.02)
Constant 0.469 1.051 -0.271 -0.804 17.312 24.263*** -1.518 0.006 0.174** -0.085 (0.31) (1.33) (0.21) (0.46) (1.22) (3.36) (0.81) (0.05) (2.76) (0.61)
Observations 418 417 418 262 218 418 330 338 337 338 Number of states 16 16 16 16 16 16 16 16 16 16 R² (within) 0.32 0.32 0.32 0.37 0.35 0.35 0.19 0.28 0.28 0.29
b) West Germany
Unconditional employment volatility Conditional employment volatility (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) Observations 340 339 340 190 140 340 270 290 289 290
Number of states 10 10 10 10 10 10 10 10 10 10
R² (within) 0.62 0.62 0.62 0.68 0.74 0.62 0.20 0.19 0.19 0.20
Table 3: Determinants of Regional Employment Volatility (Quasi Panel)
This Table presents results of fixed effects panel estimators. t-values based on robust standard errors clustered at the state-level are reported in brackets. All regressions are for all German states. Data are for the years 1975-2005. The dependent variable is the volatility of employment, calculated as the standard deviation of a non-overlapping 5-year window. ‘Unconditional’ is the unadjusted volatility of employment growth, ‘conditional’ is the volatility of the residuals of a regression of the growth rate of employment on up to five own lags, year fixed effects, and a unification dummy. See the Data Appendix for details on the specifications of the variables. ***, **, * = significant at the 1%, 5%, 10% level.
Unconditional employment volatility Conditional employment volatility (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) Volatility of output growth 0.062 0.067* 0.066* -0.026 0.132 0.056 0.076 0.034 0.019 0.044 (1.73) (1.96) (1.79) (0.38) (1.43) (1.38) (1.64) (0.65) (0.30) (1.09) Trade openness -0.065 -0.567 0.912 -0.179 0.151 0.551**
(0.27) (0.95) (1.27) (0.89) (0.88) (2.47)
Import openness -0.586** 0.551
(2.34) (1.52)
Export openness 0.448 0.978*
(0.67) (2.00)
Volatility of government revenue 0.051***
(3.04) Volatility of government spending 0.071*
(2.00)
Industry diversification -18.378 (0.99)
Unemployment -0.979
(0.62)
Service sector -1.854
(1.07)
Long-term unemployment rate -0.591
(1.00)
Degree of unionization -0.885
(0.58)
Table 3 continues …
Table 3 continued
Dependent variable: unconditional employment volatility Dependent variable: conditional employment volatility
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) Reunification dummy 0/1 0.054 0.066 0.046 -0.174* 0.276 0.338 0.205*** 0.145** 0.107* 0.126 (0.47) (0.58) (0.42) (1.77) (1.55) (1.33) (3.08) (2.21) (2.02) (1.43) Constant 0.700*** 0.778*** 0.590*** 0.718** 2.196 1.798* 0.939* -0.03 0.127 0.015 (7.41) (10.46) (4.40) (2.40) (1.20) (1.88) (1.80) (0.19) (0.99) (0.09)
Observations 82 82 82 52 32 82 62 66 66 66
Number of states 16 16 16 16 16 16 16 16 16 16
R² 0.57 0.57 0.57 0.6 0.41 0.58 0.37 0.19 0.17 0.18
Table 4: Determinants of Regional Employment Volatility (Robustness Check without City States)
This Table presents results of fixed effects panel estimators. t-values based on robust standard errors clustered at the state-level are reported in brackets. Data are for the years 1975-2005. The dependent variable is the volatility of employment computed as the squared residual of a regression of the growth rate of employment on up to five own lags, year fixed effects, and a unification dummy. See the Data Appendix for details on the specifications of the variables. ***, **,
* = significant at the 1%, 5%, 10% level.
Full Sample Excluding Hamburg Excluding Bremen Full Sample Full Sample
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) Volatility of output growth 0.056*** 0.058*** 0.050** 0.054** 0.061*** 0.061*** 0.057*** 0.059*** 0.057*** 0.060***
(3.43) (3.88) (2.55) (2.86) (3.79) (3.84) (3.42) (3.85) (3.50) (3.92) Trade openness 0.276 0.459** -0.013 0.345 0.092 (1.13) (2.44) (0.04) (1.51) (0.38)
Openness * Hamburg -0.228
(1.40)
Openness * Bremen 0.412*
. (189)
.51)
.45) Export Openness 1.047* 1.326** 0.357 1.192** 0.695
(1.83) (2.38) (0.59) (2.15) (1.05)
Export Openness * Hamburg -0.576
(1
Export Openness * Bremen 0.661
(1
Reunification dummy 0/1 -0.052 -0.043 -0.004 0.024 -0.059 -0.046 -0.055 -0.045 -0.065 -0.057 (1.27) (1.02) (0.11) (0.59) (1.00) (0.87) (1.27) (1.00) (1.39) (1.20) Constant 0.006 -0.085 -0.109 -0.212 0.141 0.063 -0.010 -0.107 0.063 -0.025 (0.05) (0.61) (1.08) (1.48) (0.89) (0.44) (0.09) (0.85) (0.49) (0.17) Observations 338 338 309 309 309 309 338 338 338 338 Number of states 16 16 15 15 15 15 16 16 16 16 R² 0.28 0.29 0.30 0.31 0.31 0.31 0.28 0.29 0.28 0.29
Table 5: Determinants of Regional Employment Volatility (Heteroscedastic Regression Model)
This Table presents results of a heteroscedastic regression model as proposed by Harvey (1967). Observations are clustered at the state level. Robust t-values are reported in brackets. Regressions for the full sample include a full set of time and state-fixed effects. Regressions for the West German sample include time fixed effects only since the model did not converge for all specifications using state fixed effects. Data are for the years 1970-2003. See the Data Appendix for details on the specifications of the variables. ***, **, * = significant at the 1%, 5%, 10% level.
Full sample West Germany
(1) (2) (3) (4) (5) (6) (7) (8)
Mean equation
Output growth 0.177** 0.185*** 0.190*** 0.187*** 0.182*** 0.182*** 0.208*** 0.154***
(2.30) (0.53) (0.59) (0.40) (6.04) (5.62) (0.20) (0.69) Wage growth -0.272* -0.265** -0.268** -0.272*** -0.186*** -0.185** -0.197*** -0.298***
(1.65) (1.96) (2.68) (2.57) (2.61) (0.46) (0.03) (3.41)
Trade openness -1.063 0.537 -0.639*** -0.250
(0.68) (0.34) (1.94) (0.80)
Import openness 0.511 -0.760***
(1.03) (5.05)
Export openness -1.629 -0.988**
(0.58) (2.38)
Unemployment -10.568** -6.779***
(0.36) (4.07)
Service sector 5.365 0.174
(0.39) (0.57)
Table 5 continues …
Table 5 continued
Full sample West Germany
(1) (2) (3) (4) (5) (6) (7) (8)
Variance equation
Output growth 0.052 0.063 0.067 0.037 0.048 0.023 -0.022 0.065 (4.08) (0.55) (4.06) (4.10) (0.35) (0.15) (7.80) (3.76) Wage growth 0.153** 0.136* 0.136** 0.156*** -0.142 -0.113 -0.008 -0.274 (2.00) (2.00) (1.83) (2.61) (0.48) (2.54) (2.89) (0.83) Trade openness 29.428 -0.617 1.684**
(0.11) (0.25) (6.32)
Import openness -3.149 1.965*
(0.44) (1.69)
Export openness -1.947 2.098
(0.59) (0.97)
Unemployment 5.447 6.279
(2.50) (0.48)
Service sector 4.187 1.681
(0.86) (0.40)
Observations 418 417 418 418 340 339 340 340