However, while historically low  4  In addition, while the changing relationship between job vacancies and unemployment – the shift in the Beveridge curve – probably does point to some greater difficulty matching jobs with workers, factors other than mismatch likely explain some of that shift.
For example, evidence suggests that firms tend to become more selective in hiring when their hiring needs are not urgent. For further discussion of these labor market issues, see Bernanke, “Recent Developments,” in note 3 and the references cited therein. See also Edward P. Lazear and James R. Spletzer (2012), “The United States Labor Market: Status Quo or a New Normal?