Date of Award




Document Type


Degree Name

Doctor of Philosophy (PhD)


Department of Economics

Content Description

1 online resource (xiv, 116 pages) : color illustrations.

Dissertation/Thesis Chair

Adrian Masters

Committee Members

Michael Sattinger, Ben Griffy


Search model, Technological changes, Labor market, Labor supply, Technology, Technological unemployment

Subject Categories

Economics | Labor Economics


This dissertation focuses on the impact of technological changes on workers based onthe task-based model. In the first chapter, I first investigate the impacts of two types of technologies on employment and job choices in the directed search model. The relationship between technology and labor with respect to complementarity and substitutability defines technology as labor-augmenting and labor-saving. Progress of labor-augmenting technology mainly works in jobs hiring highly-skilled workers in positive ways while labor-saving technological development affects jobs with middle-skilled workers in destructive ways during the last two decades in KLIPS data. The consequence of technological advances intensifies the advantage of highly skilled workers relative to unskilled workers. Then, the second part examines how employment and the adoption of new technology are affected if workers raise their skill level in response to technological changes. Two possible scenarios predict the results of an increasing supply of high-skilled workers. When firms voluntarily control the skill requirements, it causes the incidence of overqualification that increases the earning inequality, and labor-saving technologies worsen the problem in routine task jobs. However, technology innovation is accelerated. The price adjustment can naturally correct the oversupply of the highly skilled by changing the incentive to move up the job ladder. It is carried out through the reduced dispersion of technical developments and therefore decreased earning gap across tasks. In the second chapter, I examine how differently routine-biased technological changes affect unskilled workers by their innate ability and work experience. This chapter answers why some workers keep their jobs and others do not when labor-saving technologies take the worker’s role over. To focus on routine-biased technological changes, it covers high school graduates who might have either routine or manual tasks in the United States. In a random search model, workers follow the Nash bargaining wage to choose where to apply. Since the wage depends on productivity that varies by their innate ability and work experience, workers’ job search is delimited by their characteristics. The model simulates the impact of routine-biased technological changes with falling labor productivity in routine tasks, leading to wages dropping and routine jobs decreasing. From the lowest ability, those who were in the routine task sector are crowded out. The unemployment rate of unskilled workers increases even though more manual jobs are created due to lower wages. Work experience makes those who are exposed to a risk of separation survive. It distinguishes the high unemployment rate of young workers who had opportunities to accumulate work experience from a relatively low one of old workers. Therefore, while the labor-saving technological influence curtails the welfare of unskilled workers, workers with high ability and/or experience can keep.