The General Educational Development (GED) credential is issued on the basis of an eight hour subject-based test. The test claims to establish equivalence between dropouts and traditional high school graduates, opening the door to college and positions in the labor market. In 2008 alone, almost...

This paper discusses and illustrates identification problems in personality psychology. The measures used by psychologists to infer traits are based on behaviors, broadly defined. These behaviors are produced from multiple traits interacting with incentives in situations. In general, measures...

Intelligence quotient (IQ), grades, and scores on achievement tests are widely used as measures of cognition, yet the correlations among them are far from perfect. This paper uses a variety of data sets to show that personality and IQ predict grades and scores on achievement tests. Personality...