… is from page 287 of David Neumark’s and William L. Wascher’s 2008 comprehensive study, Minimum Wages; this quotation is from Table 9.1 (“Minimum wages – a scorecard”) that summarizes the authors’ findings:
Summary of evidence
Minimum wages reduce employment of low-skilled workers; adverse effects even more apparent when research focuses on those directly affected by minimum wages
Strength of conclusions
Fairly unambiguous: a handful of studies find positive effects, and some find no effect, but the preponderance of evidence points clearly to negative effects, and even more so when one focuses on the most convincing evidence.