A stochastic version of a knowledge space is developed in which knowledge states are considered as possible epochs in a subject's learning history. It specifies how a subject is channeled through and progresses along a "gradation." The model's application to artificial data is described, based on maximum likelihood methods. (TJH)

Partial knowledge was assessed in a multiple choice vocabulary test. Test reliability and concurrent validity were compared using Rasch-based dichotomous and polychotomous scoring models. Results supported the polychtomous scoring model, and moderately supported J. O'Connor's theory of vocabulary acquisition. (Author/GDC)

In all latent trait models there is an equation which describes the probabilistic outcome of the interaction of a person with a known ability and an item with a known difficulty. This modeled outcome can be compared to the observed outcome, and the residuals can be summed over the items to assess the fit of the person to the model. Various…

In the answer-until-correct mode of multiple-choice testing, respondents are directed to continue choosing among the alternatives to each item until they find the correct response. There is no consensus as to how to convert the resulting pattern of responses into a measure because of two conflicting models of item response behavior. The first…