Choice of employment status and the wages of employees and the self‐employed: Some further evidence
利用1978年美国年轻男性NLS数据，复制了Rees和Shah基于英国数据的研究发现，通过估计考虑样本选择性的工资方程，证实雇员和自雇者子样本中存在正向选择偏差。
Abstract Using US data drawn from the 1978 young men NLS sample, this paper replicates a key finding reported by Rees and Shah in their analysis of self‐employment using large‐scale British data. A wage equation, which allows for sample selectivity, is estimated for subsamples of employees and the self‐employed. Despite differences between the data sets and the variables analysed, the NLS results support Rees and Shah's conclusion that there is positive selection bias in the observed earnings of employees.