We re-examine the evidence presented by Neumark and Wascher (1992) on
the employment effect of the minimum wage. We find three critical flaws in
their analysis. First, the school enrollment variable that plays a pivotal
role in their specifications is derived on the false assumption that
teenagers either work or attend school. Measurement error biases
contaminate all the empirical estimates that use this enrollment variable.
Second, Neumark and Wascher measure the effect of the minimum wage by a
coverage-weighted relative minimum wage index. This variable is negatively
correlated with average teenage wages. Taken literally, their results show
that a rise in the coverage-weighted relative minimum wage lowers teenage
wages. Examining the direct effects of state-specific minimum wages, we
find that increases in state minimum wages raise average teenage wages but
have essentially no employment effects.
Finally, a careful analysis of Neumark and Wascher's data shows that
subminimum wage provisions are rarely used. This casts doubt on their
claim that subminimum provisions blunt any disemployment effect of the
minimum wage.
Neumark and Wascher contend that other minimum wage studies are biased
by failing to control for school enrollment, and by failing to consider the
lagged effects of minimum wages. We re-analyze the experiences of
individual states following the April 1990 increase in the Federal minimum
wage, allowing for a full year lag in the effect of the law and controlling
for changes in (properly measured) enrollment rates. Contrary to their
claims, allowing for lagged effects and controlling for enrollment status
actually strengthens the conclusion that the 1990 increase in the Federal
minimum had no adverse employment effect.