A marginal maximum likelihood estimation algorithm is presented for the ordered partition model of M. Wilson that does not require the set of available responses to be fully ordered. The model and its estimation algorithm are illustrated in a comparison of alternative scoring schemes for open-ended science items. (SLD)

Defines one approach to problem solving in terms of student use of algorithms to find their solutions and gives examples. Discusses how problems and algorithms relate to each other. Describes strategies for teaching problem solving using algorithms. (CW)

Discusses the use of a historical profile for illustrating the significance of the mathematical components of scientific laws. Addresses the need for the purposive use of scientific laws rather than the blind substitutionary procedures characteristic of most problem solvers. Claims the approach has the potential for increasing female participation…