Looking for a Needle in a Haystack? A Re‐examination of the Time Series Relationship between Teenage Employment and Minimum Wages in the United States*
重新审视美国最低工资与青少年就业的时间序列关系，发现传统模型因无法捕捉趋势、周期和季节成分的变化而失效，提出随机成分替代方法，并证实最低工资对青少年就业有显著的负向影响。
Abstract The work of Card and Krueger has cast doubt on the nature of the relationship between the minimum wage and teenage employment in the United States. The earlier ‘consensus’ finding of a small but statistically significant negative effect was based on time series data whereas Card and Krueger's findings are based mainly on cross‐section data. In this article, we re‐examine the time series relationship between minimum wage and teenage employment. We find that previous models break down due to their inability to capture changes in the trend, cyclical and seasonal components of teenage employment. We propose an alternative approach in which these components are treated as stochastic components and which contains the traditional, deterministic approach as a special case. The model when estimated up to 1979 accurately predicts what happens to teenage employment subsequently, when the minimum wage was frozen after 1981 and then increased quite substantially in the early 1990s. Moreover, we find that there is a significant, negative effect of the minimum wage on teenage employment and its size has hardly changed during the 1980s and early 1990s.