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Mooijaart, Ab; van der Heijden, Peter G. M. – Psychometrika, 1992
It is shown that it is not easy to apply the EM algorithm to latent class models in the general case with equality constraints because a nonlinear equation has to be solved. A simpler condition is given in which the EM algorithm can be easily applied. (SLD)
Descriptors: Algorithms, Equations (Mathematics), Estimation (Mathematics), Mathematical Models
Longford, Nicholas T. – 1993
An approximation to the likelihood for the generalized linear models with random coefficients is derived and is the basis for an approximate Fisher scoring algorithm. The method is illustrated on the logistic regression model for one-way classification, but it has an extension to the class of generalized linear models and to more complex data…
Descriptors: Algorithms, Estimation (Mathematics), Maximum Likelihood Statistics, Scoring
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Rindskopf, David – Psychometrika, 1992
A general approach is described for the analysis of categorical data when there are missing values on one or more observed variables. The method is based on generalized linear models with composite links. Situations in which the model can be used are described. (SLD)
Descriptors: Algorithms, Classification, Data Analysis, Estimation (Mathematics)
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Cheng, Philip E.; Liou, Michelle – Applied Psychological Measurement, 2000
Reviewed methods of estimating theta suitable for computerized adaptive testing (CAT) and discussed the differences between Fisher and Kullback-Leibler information criteria for selecting items. Examined the accuracy of different CAT algorithms using samples from the National Assessment of Educational Progress. Results show when correcting for…
Descriptors: Ability, Adaptive Testing, Algorithms, Computer Assisted Testing
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Zeng, Lingjia – Applied Psychological Measurement, 1997
Proposes a marginal Bayesian estimation procedure to improve item parameter estimates for the three parameter logistic model. Computer simulation suggests that implementing the marginal Bayesian estimation algorithm with four-parameter beta prior distributions and then updating the priors with empirical means of updated intermediate estimates can…
Descriptors: Algorithms, Bayesian Statistics, Estimation (Mathematics), Statistical Distributions
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Seltzer, Michael H.; And Others – Journal of Educational and Behavioral Statistics, 1996
The Gibbs sampling algorithms presented by M. H. Seltzer (1993) are fully generalized to a broad range of settings in which vectors of random regression parameters in the hierarchical model are assumed multivariate normally or multivariate "t" distributed across groups. The use of a fully Bayesian approach is discussed. (SLD)
Descriptors: Algorithms, Bayesian Statistics, Estimation (Mathematics), Multivariate Analysis
Knol, Dirk L.; ten Berge, Jos M. F. – 1987
An algorithm is presented for the best least-squares fitting correlation matrix approximating a given missing value or improper correlation matrix. The proposed algorithm is based on a solution for C. I. Mosier's oblique Procrustes rotation problem offered by J. M. F. ten Berge and K. Nevels (1977). It is shown that the minimization problem…
Descriptors: Algorithms, Computer Software, Correlation, Estimation (Mathematics)
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Knol, Dirk L.; ten Berge, Jos M. F. – Psychometrika, 1989
An algorithm, based on a solution for C. I. Mosier's oblique Procrustes rotation problem, is presented for the best least-squares fitting correlation matrix approximating a given missing value or improper correlation matrix. Results are of interest for missing value and tetrachoric correlation, indefinite matrix correlation, and constrained…
Descriptors: Algorithms, Correlation, Equations (Mathematics), Estimation (Mathematics)
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Zielman, Berrie; Heiser, Willem J. – Psychometrika, 1993
An algorithm based on the majorization theory of J. de Leeuw and W. J. Heiser is presented for fitting the slide-vector model. It views the model as a constrained version of the unfolding model. A three-way variant is proposed, and two examples from market structure analysis are presented. (SLD)
Descriptors: Algorithms, Classification, Equations (Mathematics), Estimation (Mathematics)
Woodruff, David J.; Hanson, Bradley A. – 1996
This paper presents a detailed description of maximum parameter estimation for item response models using the general EM algorithm. In this paper the models are specified using a univariate discrete latent ability variable. When the latent ability variable is discrete the distribution of the observed item responses is a finite mixture, and the EM…
Descriptors: Ability, Algorithms, Estimation (Mathematics), Item Response Theory
Peer reviewed Peer reviewed
Gigerenzer, Gerd; Hoffrage, Ulrich – Psychological Review, 1995
It is shown that Bayesian algorithms are computationally simpler in frequency formats than in the probability formats used in previous research. Analysis of several thousand solutions to Bayesian problems showed that when information was presented in frequency formats, statistically naive participants derived up to 50% of inferences by Bayesian…
Descriptors: Algorithms, Bayesian Statistics, Computation, Estimation (Mathematics)
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McDonald, Roderick P.; Hartmann, Wolfgang M. – Multivariate Behavioral Research, 1992
An algorithm for obtaining initial values for the minimization process in covariance structure analysis is developed that is more generally applicable for computing parameters connected to latent variables than the currently existing ones. The algorithm is formulated in terms of the RAM model but can be extended. (SLD)
Descriptors: Algorithms, Correlation, Equations (Mathematics), Estimation (Mathematics)
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Berger, Martijn P. F. – Journal of Educational Statistics, 1994
Problems in selection of optimal designs in item-response theory (IRT) models are resolved through a sequential design procedure that is a modification of the D-optimality procedure proposed by Wynn (1970). This algorithm leads to consistent estimates, and the errors in selecting the abilities generally do not greatly affect optimality. (SLD)
Descriptors: Ability, Algorithms, Estimation (Mathematics), Item Response Theory
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Maris, Eric; And Others – Psychometrika, 1996
Generalizing Boolean matrix decomposition to a larger class of matrix decomposition models is demonstrated, and probability matrix decomposition (PMD) models are introduced as a probabilistic version of the larger class. An algorithm is presented for the computation of maximum likelihood and maximum a posteriori estimates of the parameters of PMD…
Descriptors: Algorithms, Diagnostic Tests, Estimation (Mathematics), Matrices
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Hutchinson, J. Wesley; Mungale, Amitabh – Psychometrika, 1997
A nonmetric algorithm, pairwise partitioning, is developed to identify feature-based similarity structures. Presents theorems about the validity of the features identified by the algorithm, and reports results of Monte Carlo simulations that estimate the probabilities of identifying valid features for different feature structures and amounts of…
Descriptors: Algorithms, Error of Measurement, Estimation (Mathematics), Identification
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