Fractional Integration and the Dynamics of UK Unemployment*
用分数积分方法估计英国失业的动态行为，发现失业是均值回归的，但受冲击后恢复时间远超文献此前报告。
Abstract This article is concerned with estimating the dynamic behaviour of UK unemployment using fractional integration methods. The question it considers is whether an unemployment model using a relatively small set of determinants of unemployment is consistent with the persistence which estimates an integrated model yield, or the much long‐lasting estimates obtained from fractional integration. Our empirical tests favour the latter version. The results show that when accounting for UK unemployment in terms of lagged values of the real oil price and the real interest rate, unemployment appears fractionally integrated. This finding means that although unemployment is mean reverting, once it is shocked it may take a very long time to recover, and our estimates of the response times are considerably in excess of those previously reported in the literature.