The importance of the distinction between long- and short-term unemployment in UK macroeconometric models

This paper examines the degree of support for distinct duration effects on wages across a variety of wage equations, and investigates their importance in full simulations with three large-scale UK macroeconometric models. The paper begins by highlighting deficiencies both in the way that existing models determine the duration structure of unemployment and in the specification of long-term unemployment in the wage equation. By constructing a single preferred wage equation we test hypotheses relating to duration effects and, although tests are not conclusive, find some support for the use of short-term unemployment in the wage equation. However, it is also shown that the response of wages to changes in unemployment is similar regardless of whether aggregate or short-term unemployment is used in the wage equation, although this does not hold when the duration structure of unemployment changes radically. By substituting revised equations into the models we show that these results carry over to full model simulations. Thus although neglect of duration effects may not be crucial in assessing the effectiveness of standard macro policy instruments, this is not likely to be true when evaluating policies which are deliberately targeted at the long-term unemployed.