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Employment, and Unemployment Macroeconomics Chapter 9 42 The Labor Force, Employment, and Unemployment ? Job Separations, Job Finding, and the Natural Unemployment Rate ? The change in the number of persons employed over a month, ?L, is given by ?? L = ? U ? σ L = job findings? job separations ? The longrun levels of L and U are constant. ??L=0 ? ? U = σ L ? job findings= job separations Macroeconomics Chapter 9 43 The Labor Force, Employment, and Unemployment ? Job Separations, Job Finding, and the Natural Unemployment Rate ? Key equation (natural unemployment rate): un = σ/(? + σ) ? A higher jobseparation, σ , raises the natural unemployment rate, un, whereas a higher jobfinding rate, ?, lowers un. Macroeconomics Chapter 9 44 The Labor Force, Employment, and Unemployment ? Economic Fluctuations, Employment, and Unemployment ? An adverse shock to the technology level, A, reduces the marginal product of labor for the typical worker and job. The jobfinding rate, ?, falls because market opportunities became poorer—probably temporarily—relative to the real ine received while unemployed, ω. Macroeconomics Chapter 9 45 The Labor Force, Employment, and Unemployment Macroeconomics Chapter 9 46 The Labor Force, Employment, and Unemployment ? Vacancies ? An increase in the value of prospective marginal products, MPL, raises the number of job openings ? An increase in the real wage rate, w/P, required to get workers to accept jobs lowers the number of job openings. ? A reduction in costs of posting jobs and processing applications raises the number of job openings. Macroeconomics Chapter 9 47 The Labor Force, Employment, and Unemployment ? Vacancies ? An increase in the technology level, A, raises the MPL. For given real wage rates, w/P, firms post more job openings. Therefore, job vacancies increase. ? An unfavorable shock reduces vacancies. ? Thus, our prediction is that vacancies are procyclical — high in booms and low in recessions. Macroeconomics Chapter 9 48 The Labor Force, Employment, and Unemployment Macroeconomics Chapter 9 49 The Labor Force, Employment, and Unemployment