Showing papers on "Probabilistic latent semantic analysis published in 1982"

Some Latent Trait Theory in a Multidimensional Latent Space.

Abstract: ABSTRACT This paper reviews the existing multidimensional item response theory (IRT) models and demonstrates how one of the models can be applied to estimation of abilities from a test measuring more than one dimension. The purposes of this paper were threefold. First, the fundamental concepts required when considering multidimensional models for the interaction of a person and a test item were defined. These concepts incluAed the multidimensional latent space, the item difficulty function, and the item discrimination function. These definitions were conceived as multidimensional generalizations of similar concepts in unidimensional IRT models. Second, six existing multidimensional models were reviewed and, on the basis of their similarities, were classified into three general categories. The characteristics of these categories were described, and the general Rasch model was selected for further study on the basis of ease of parameter estimation. Third, estimation procedures for the parameters of the general Rasch model were described and applied to a set of simulation data that had been generated according to a two-dimensional special case of the model. The results indicated that a very close correspondence had been obtained between the estimated item parameters and those used to generate the simulation data. (PN)

Causal Analysis and Latent Class Models: An Application to a Communication Hierarchy of Effects Model:

Abstract: The authors illustrate the use of latent structure analysis to test, in a confirmatory sense, causal hypotheses in an experimental design setting. Two latent factors conceptualized as arousal and y...

The Metric of the Latent Variables in a LISREL-IV Analysis

Abstract: A potential source of confusion in the interpretation of a LISREL-IV analysis is the metric of the latent variables. This paper demonstrates that fixing the pattern coefficient of one of the indicators of each latent variable to 1.0 results in an arbitrary and meaningless metric which is usually different for each latent variable. Since many of the parameter estimates such as the pattern coefficients, the factor loadings, and the variance-covariance matrix of the latent variables are a function of the metric of the latent variables, much of the LISREL-IV output may be uninterpretable. This paper demonstrates how to specify a priori the variances of the latent variables in a LISREL-IV analysis.

Semantic Development of Simple Classification Terms

Abstract: One of the more complex problems of language acquisition concerns semantic development. Neither the form nor the underlying mechanisms of the evolution of meaning are well understood. It does, however, seem clear that the meanings of some terms do change with age. For example, small children appear to have difficulties distinguishing the meaning of certain opposing terms, such as “less” and “more” (Palermo,1973) or “different” and “same” (Webb et al.,1974), difficulties not found in older children. It is nontheless often difficult to extrapolate from this kind of data to descriptions of semantic structure.