The Butz-Ward Fertility Model in the Light of More Recent Data
用新数据检验巴茨-沃德1979年提出的反周期生育率模型，发现原模型结果受早期数据局限，更新后模型不成立。
Butz and Ward (B-W) in their 1979 article Emergence of Countercyclical US Fertility postulated a change in the longstanding pattern of procyclical fertility first documented by Dorothy Thomas in 1927. The paucity of published data on female wages led B-W to approximate a time series using a number of disparate sources. There has been some criticism of the B-W methodology focusing mainly on the problem of autocorrelation in time series analysis and misspecification. 15 years after the 1979 article a great deal of both micro and macro data exist which were not available at the time of the original B-W research. The author tests the robustness of the B-W results by first updating them using their original sources then with data drawn from the March Current Population Survey (CPS). The results indicate that there are wide divergences between the original B-W estimates of female wages and the CPS time series. In particular the CPS time series shows that much of the dramatic increase in the female hourly wage in the 1960s as estimated by B-W appears to have been the result of the proxy they used for average hours worked. That proxy was a series of average hours of all workers in the retail trade which trends sharply downward contrary to the actual pattern for married women. Estimates of the B-W model using the new CPS series fail to work neither in terms of the signs nor significance of the variables. Even using the original B-W data their model no longer fits in the period after about 1954. Their results seem to have been driven by relationships exhibited during 1947-54 almost 10 years before the increases in female labor force participation which began in the 1960s.