Matching efficiency is the productivity of the process for matching job-seekers to available jobs. Job-finding is the output; vacant jobs and active job-seekers are the inputs. We develop a framework for measuring matching productivity when the population of job-seekers is heterogeneous. We find that overall matching efficiency declined smoothly over the period from 2001 through 2013. Measures of matching efficiency that neglect heterogeneity among the unemployed and also neglect job-seekers other than the unemployed suggest a large 28 percent decline in efficiency between 2007 and 2009. Most of this apparent decline results from changes in the composition of job-seekers.
"Measuring Job-Finding Rates and Matching Efficiency with Heterogeneous Job-Seekers."
American Economic Journal: Macroeconomics,