The possibility is considered that research on intelligence is entering or is about to enter a time of crisis. First, it is suggested that the decline of the psychometric paradigm as the primary means for studying intelligence was due in part to the failure of users of the paradigm to meet in a highly successful way four challenges that confronted…

The decline of the psychometric paradigm for studying intelligence was due in part to its failure to meet four challenges. On the surface, users of the information-processing paradigms seem successfully to have met these challenges, but at a deeper level, the level of success is not so great. (Author/BW)

The uses of data on siblings for educational and psychological research purposes are explained. Examples are based on empirical data. Five types of research problems, using sibling data, are explored: (1) statistical control of family background variance in psychological or educational studies which use analysis of covariance (ANCOVA) or multiple…