OLS Regressions with Private and Public Sector Union Density
A. Dependent Variable: Percent Change in Union Density 1953-2000 Change in Union Density 1939-1953 .006∗ .004
[0.003] [0.003] Observations 47 47
R2 0.074 0.48
Covariates E, D
B. Dependent Variable: Change in Public Sector Density 1953-2000 Change in Union Density 1939-1953 2.4∗∗∗ 2.1∗∗∗
[0.41] [0.45] Observations 47 47
R2 0.43 0.86
Covariates E, D
Table 3.1 The models presented are least-squares estimates of equation 1. The primary independent variable is the change in union density between 1939 and 1953. D represents a robust set of demographic controls, which are fully listed in the Data Appendix while E represents a set of employment and industrial controls. Source: Gallup (1939, 1945) Troy (1957), Hirsch and Macpherson (2010), County and State Databook (2000), Census of Manufacturers (1939).
2SLS Instrumental Variables Analysis
Stage 1. Dependent Variable: Change in Union Density 1939-1953 War Industries 150.616∗∗∗ 122.972∗∗∗ [28.733] [228.416] Total Contracts 1.201∗∗∗ .761∗∗∗ [0.321] [0.282] Observations 47 47 47 R2 0.83 0.88 0.91 Covariates E,D E, D E, D
Stage 2a. Dependent Variable: Percent Change in Union Density 1953-2000 Change in Union Density 1939-1953 .0126∗∗ .0148∗ .0131∗∗
[0.00599] [0.00829] [0.00581]
Observations 47 47
R2 0.89 0.89 0.89
Covariates E,D E, D E, D Stage 2b. Dependent Variable: Public Sector Union Density in 2000 Change in Union Density 1939-1953 2.846∗∗∗ 3.174∗∗∗ 2.537∗∗∗
[0.618] [0.724] [0.676]
Observations 47 47
R2 0.46 0.33 0.33
Covariates E,D E, D E, D
Table 3.2 The models presented are two-stage least-squares estimates of equations 2 and 3. In the first stage, the change in union density between 1939 and 1953 is regressed on the share of workers in a war industry or the value of allocated war contracts. Stage 2a has the percentage change in total union density as the dependent variable while Stage 2b has the change in public sector union density. Specification one includes war contracts, specification two includes the share of workers in war industries, and specification three includes both instruments. D represents a robust set of demographic controls, which are fully listed in the Data Appendix while E represents a set of employment and industrial controls. Source: Gallup (1939, 1945) Troy (1957), Hirsch and Macpherson (2010), County and State Databook (2000), Census of Manufacturers (1939).
Instrument Variables Validity Test
Dependent Variable - Union density
Year 1939 1953 Pre-War Trend War Industries 0.412 1.60∗∗ -3.54 [0.384] [0.743] [93.545] Total Contracts 0.00288 0.0244∗∗∗ 1.06 [0.00277] [0.00559] [0.628] Obs. 47 47 47 Covariates E, D E, D E, D
Table 3.3 OLS regressions of union density in 1939 or 1953 and the pre-war change in union density on the share of workers employed in war industries during World War II and the value of war contracts allocated to a state. D represents a robust set of demographic controls, which are fully listed in the Data Appendix while E represents a set of employment and industrial controls. Source: Gallup (1939, 1945) Troy (1957), Hirsch and Macpherson (2010), County and State Databook (2000), Census of Manufacturers (1939).
Reduced Form Regressions Using the Instrumental Variables
A. Dependent Variable: Percent Change in Union Density 1953-2000 War Industries 0.00453 -0.00210 [0.00329] [0.00768] Total Contracts 1.317 2.223∗ [1.000648] [1.151] Observations 47 47 R2 0.13 0.35 Covariates E, D
B. Dependent Variable: Change in Public Sector Density 1953-2000 War Industries 1.151∗∗∗ 2.937∗∗ [0.387] [0.937] Total Contracts 300.198∗∗ 190.0944 [117.898] [140.455] Observations 47 47 R2 0.46 0.57 Covariates E, D
Table 3.4 The models presented are least-squares estimates. D represents a robust set of demographic controls, which are fully listed in the Data Appendix while E represents a set of employment and industrial controls. Source: Gallup (1939, 1945) Troy (1957), Hirsch and Macpherson (2010), County and State Databook (2000), Census of Manufacturers (1939).
OLS Mechanism Regressions
A. Dependent Variable: Number of Union Elections post-1964 Change in Union Density 1939-1953 182.83∗∗∗ 72.08∗∗
[60.57] [24.43]
Observations 47 47
R2 0.18 0.92
Covariates E, D
B. Dependent Variable: Public Sector Labour Law Index Change in Union Density 1939-1953 -0.0043 -0.0043
[0.0068] [0.0081]
Observations 47 47
R2 0.01 0.68
Covariates E, D
C. Dependent Variable: Right-to-Work Status Change in Union Density 1939-1953 -0.054∗∗∗ -0.046∗∗∗ [0.013] [0.015]
Observations 47 47
R2 0.28 0.46
Covariates E, D
D. Dependent Variable: Number of ULP Charges per million members post-1964 Change in Union Density 1939-1953 1072.55∗∗ 358.91∗∗
[416.41] [172.90]
Observations 47 47
R2 0.14 0.93
Covariates E, D
Table 3.5 The models presented are least-squares estimates of equation 1, but with alternate dependent variables: A. The number of union elections post-1964 is regressed on the the change in union density between 1939 and 1953; B. The value of a public sector labour law index is regressed on the the change in union density between 1939 and 1953; C. Aright-to-work dummy is regressed on the the change in union density between 1939 and 1953; D. The number of ULPs post-1964 is regressed on the the change in union density between 1939 and 1953. D represents a robust set of demographic controls, which are fully listed in the Data Appendix while E represents a set of employment and industrial controls. Source: Gallup (1939, 1945) Troy (1957), Hirsch and Macpherson (2010), County and State Databook (2000), Census of Manufacturers (1939).
IV Second Stage Mechanism Regressions
A. Dependent Variable: Number of Union Elections post-1964 Change in Union Density 1939-1953 264.64∗∗∗ 86.66∗ 151.17∗∗∗
[84.33] [50.97] [48.09]
Observations 47 47 47
R2 0.91 0.88 0.91
Instruments 1, 2 2 1
Covariates E, D E, D E, D
B. Dependent Variable: Public Sector Labour Law Index Change in Union Density 1939-1953 -0.0019 0.010 -0.010
[0.011] [0.012] [0.012]
Observations 47 47 47
R2 0.07 0.04 0.08
Instruments 1, 2 2 1
Covariates E, D E, D E, D
C. Dependent Variable: Right-to-Work Status
Change in Union Density 1939-1953 -0.054∗ -0.094∗∗∗ -0.079∗∗∗ [0.032] [0.030] [0.026]
Observations 47 47 47
R2 0.29 0.34 0.32
Instruments 1, 2 2 1
Covariates E, D E, D E, D
D. Dependent Variable: Number of ULP Charges post-1964 Change in Union Density 1939-1953 550.802∗∗ 967.648∗∗∗ 220.456∗
[220.172] [291.858] [240.151]
Observations 47 47 47
R2 0.90 0.87 0.90
Instruments 1, 2 2 1
Covariates E, D E, D E, D
Table 3.6 The models presented are the second stage of the least-squares estimates of equations 2 and 3, but with alternate dependent variables: A. The number of union elections post-1964 is regressed on the the change in union density between 1939 and 1953; B. The value of a public sector labour law index is regressed on the the change in union density between 1939 and 1953; C. Aright-to-work dummy is regressed on the the change in union density between 1939 and 1953; D. The number of ULPs post-1964 is regressed on the the change in union density between 1939 and 1953. D represents a robust set of demographic controls, which are fully listed in the Data Appendix while E represents a set of employment and industrial controls. Source: Gallup (1939, 1945) Troy (1957), Hirsch and Macpherson (2010), County and State Databook (2000), Census of Manufacturers (1939).
Summary Statistics Over Time
Year Membership Density Relative Var of Density Relative Var of Share Density Raw Corr With 2004 Density Rank Corr With 2004 History
1939 8.8 21.5 3.13 1.60 0.58 0.61 Start of World War 2. The National Industrial Recov- ery Act and the Wagner Act are passed in 1933 and 1935 respectively. The Fair Labor Standards Act is passed in 1938. 1953 16.2 32.6 4.31 0.94 0.78 0.79 Earliest post-war data
available. The Taft- Hartley Act is passed in 1947. Florida and Arkansas pass the first right-to-work legislation in 1944. Passage of the LMRDA.
1964 17.9 29.3 3.63 0.871 0.87 0.88 The AFL and CIO merge in 1955. The Landrum- Griffith Act is passed in 1959. The National Farm Workers Association (later the UFW) is founded in 1962.
1974 18.2 26.2 2.70 0.86 0.88 0.90 Passage of OSHA in 1970. First major postal worker strike. UFW reach an agreement with graper growers.
1984 17.3 19.1 1.72 0.84 0.94 0.92 Reagan breaks the PATCO in 1981, resulting in a mas- sive decrease in union or- ganizing and an acceler- ated decline in union mem- bership.
1994 16.7 15.7 1.25 0.84 0.95 0.94 NAFTA is passed in 1994.
2004 15.4 12.6 1 1 1 1
Table 3.7 Figures generated as outlined in the paper body from Source: Gallup (1937, 1939, 1945), Troy (1957), Garlock (2009), and Hirsch and Macpherson (2010).