Degree Name

Master of Arts (MA)

Semester of Degree Completion


Thesis Director

Patrick M. Lenihan


The union membership in the United States has declined since 1970 and reached less than 14 percent of labor force in 1989. A number of studies have been conducted to examine the causes of decline in union membership. Among researchers nearly all believed that structural change in the United States economy plays an important role. The theories of managerial opposition and substitution of government and employers for unions were also supported by many researchers. This study examined the effect of the number of female and part-time workers from the labor force as a measure for structural change in the economy. The number of unfair labor practice filed by the union members was used to show the effect of managerial opposition. For indicating the effect of governmental substitution, the number of workers that received unemployment insurance from government were chosen. In addition, direct foreign investment as a proxy for foreign competition and a dummy variable for political party of the president to show the administration and legislation effect were used.

Three multiple regressions were performed, using data from 1961-1989. Data were obtained from Economic Report of President, Statistical Abstract of the United States, and Monthly Labor Review. In the first regression model the absolute value of the independent variables were used. The results showed that only the absolute values of part-time workers and the president's political party have negative and significant effects on the percentage of unionized workers to the labor force. The effect of percentage change of the independent variables on the percentage of unionized workers in labor force is shown in the results of the second regression model. The results imply that there is a negative but not significant relationship of percentage of female and part-time workers to labor force and the president's political party with the dependent variable. There is also a significant effect of direct foreign investment in the United States and the insured unemployed to unemployment ratio on the dependent variable. Because of the high degree of intercorrelation between the percentage of female and part-time workers to total labor force the third regression model was run without the variable of part-time workers. The results showed a negative and significant effect of percentage female workers to labor force on the percentage of unionized workers to labor force. In addition, percentage change of direct foreign investment and the number of insured unemployed divided by total unemployment have positive and significant effect on the percentage of the unionized workers.