Pupils' difficulties in solving word problems continue to attract attention: while researchers highlight the importance of relational reasoning and modelling, school curricula typically use short word problems to develop pupils' knowledge of arithmetic operations and calculation strategies. The Relational Paradigm attributes the leading role in…

Two models of library circulation, the Markov model and the mixed Poisson Model, are applied to circulation statistics from the University of Saskatchewan. Goodness-of-fit tests indicate that neither model fits the data; in both cases, the set of noncirculating items is larger than that predicted by the model. (Author/LRW)

This paper reviews methods which have been used to identify and validate learning hierarchies. Specifically, three methods which reflect the notion of a relatively inviolate sequence are discussed and compared. Two of the psychometric methods compare pairs of skills, the ordering-theoretic method (Bart and Krus) and the test of inclusion (White…