The time-series process postulated is a more general form of the integrated moving average model than for which estimation and testing procedures were formerly available. (Author)

The development of the concept of seriation was studied for 415 children, ranging in age from 3 to 9 years. The subjects were required to learn to identify the larger or smaller object in a two stimulus series, the smallest or middle-sized object in a three stimulus series, and the largest or next to the smallest in a four stimulus series. The end…

People categorized pairs of perceptual stimuli that varied in both category membership and pairwise similarity. Experiments 1 and 2 showed categorization of 1 color of a pair to be reliably contrasted from that of the other. This similarity-based contrast effect occurred only when the context stimulus was relevant for the categorization of the…

The author's secondary school mathematics students have often reported to her that quadratic relations are one of the most conceptually challenging aspects of the high school curriculum. From her own classroom experiences there seemed to be several aspects to the students' challenges. Many students, even in their early secondary education, have…