Over the last two decades, earnings in the United States increased at the top and at the bottom of the wage distribution but not in the middle - the intensely debated middle class squeeze. At the same time there was a substantial decline of employment in middle-skill production and clerical...

Becker's theory of human capital predicts that minimum wages should reduce training investments for affected workers because they prevent these workers from taking wage cuts necessary to finance training. In contrast, in noncompetitive labor markets, minimum wages tend to increase training of...