Correct simple formulas are provided for the value of phi needed to use the commonly available Pearson and Hartley power charts in determining the power of hypothesis tests involving simple degree-of-freedom comparisons in the fixed effects analysis of variance. (LMO)

Proposes an alternative methodology for handling queries with weighted search terms or search criteria in a fuzzy environment as a means of improving the performance of information retrieval systems. (EM)

This study formulates a property of a quantification method, the principle of equivalent partitioning. When used with Guttman's principle of internal consistency, the combination allows the analysis of correlational data in terms of the variate(s) chosen by the investigator. Applications to multiple-choice, rank-order, and paired comparison data…

A general class of differentiation indices is introduced for profiles of scores. Their ordinal properties and an application to Holland's classification system are examined. Comparison with other suggested indices is performed both theoretically and empirically. (Author)

The extension of regression estimation and poststratification to factor analysis is considered. These methods may be used either to improve the efficiency of estimation or to adjust for the effects of nonrandom selection. The estimation procedure may be formulated in a LISTREL framework. (Author/LMO)

Under the assumption of normalcy, a formula is derived for the reliability of the maximum score. It is shown that the maximum score is more reliable than each of the single observations but less reliable than their composite score. (Author/LMO)

Empirical data from a farm-level survey of 1,548 small farmers in Guatemala show that there appears to be a threshold effect and that four or more years of education are needed to have a measurable impact on farm productivity. Appended are 13 references. (MLF)

A sample of 328 freshman economics students is disaggregated by the students' gender, previous knowledge of economics, attitudes toward economics, and innate abilities. Results show that students learn more economics if they take microeconomics before macroeconomics. Appended are 14 references. (MLF)

Empirical estimates of production frontiers and average production functions performed for selected public elementary school districts in California support the hypothesis of an optimal school size model. Some policy implications of the results are briefly analyzed. Appended are 16 references. (MLF)

On the occasion of Psychometrika's fiftieth anniversary, the past twenty-five years' developments in mental test theory are reviewed. Psychometrika articles treating topics in test theory are listed in a bibliography. (Author/LMO)

The compatibility of the polychotomous Rasch model with dichotomization of the response continuum is discussed. It is argued that in the case of graded responses, the response categories presented to the subject are essentially an arbitrary polychotomization of the response continuum. (Author/LMO)

A neuromathematical model of information processing applied to science learning is expanded to include two coefficients representing the motivational state of the learner. The inclusion of these coefficients (which are described) permits modeling of the effects of variations in motivation on the rate and amount of information in learning tasks.…

A classification of the simple combinatorial configurations which correspond to various cases of distribution and ordering of objects into boxes is given (in French). Concrete descriptions, structured relations, translations, and formalizations are discussed. (MNS)

Presents the bivariate normal probability distribution as a method for estimating the prevalence of giftedness. The bivariate model requires the specification of two cutoff values for two selection variables and information regarding the size of the correlations between variables. The use and interpretation of bivariate estimates is discussed.…

This paper reports on the mathematical modelling of four classes of 4th-grade children as they worked on a modelling problem involving the selection of an Australian swimming team for the 2004 Olympics. The problem was implemented during the second year of the children's participation in a 3-year longitudinal program of modelling experiences…