Describes a computerized decision support system based on circulation data that was developed to assist the Indianapolis-Marion County Public Library in materials acquisition budgeting and other library management decision making. The budget allocation model is explained, and implementation and testing of the decision support system is described.…

A procedure is described for estimating the reliability and conditional standard errors of measurement of scale scores incorporating the discrete transformation of raw scores to scale scores. The method is illustrated using a strong true score model, and practical applications are described. (SLD)

Effects of dimensionality on ability estimation of an adaptive test were examined using generated data in Bayesian computerized adaptive testing (CAT) simulations. Generally, increasing interdimensional difficulty association produced a slight decrease in test length and an increase in accuracy of ability estimation as assessed by root mean square…

Scaling methodologies used in analysis of National Assessment of Educational Progress (NAEP) surveys since 1984 are reviewed. The plausible values methodology developed for NAEP scale-score analyses is described in the contexts of item response theory and average response method scaling. Current NAEP research in scaling is discussed. (SLD)

Presents a problem to determine conditions under which two identical masses, constrained to move along two perpendicular wires, would collide when positioned on the wires and released with no initial velocity. Offers a solution that utilizes the position of the center of mass and a computer simulation of the phenomenon. (MDH)

The exact and closed-interval area measures for detecting differential item functioning are compared for actual data from 1,000 African-American and 1,000 white college students taking a vocabulary test with items intentionally constructed to favor 1 set of examinees. No real differences in detection of biased items were found. (SLD)

For paired rankings data, a statistical test is proposed to detect whether subjects' posttreatment rankings have moved systematically toward an unknown ranking or set of rankings. Using paired-rankings from 38 ninth graders in a writing and literary criticism course, graphical methods for representing the data are presented. (SLD)

Discussion of the growth of the Internet focuses on the rate of growth based on three measurements of changes in reachable Internet services: (1) the rate at which sites initiate network connectivity; (2) the rate at which sites become directly connected; and (3) the rate at which sites distance themselves, usually for security reasons. (Contains…

Item response theory (IRT) is used to develop a form of adjusted cumulative grade point average (GPA) for use in predicting college academic performance appropriately for males and females. For 1,564 students at Stanford University (California), the IRT-based GPA was more predictable from preadmission measures than the cumulative GPA. (SLD)

An evaluation of the rules-of-thumb used to determine the minimum number of subjects required to conduct multiple regression analyses suggests that researchers who use a rule of thumb rather than power analyses trade simplicity of use for accuracy and specificity of response. Insufficient power is likely to result. (SLD)

Forming the matching variable for the Mantel-Haenszel differential item functioning (DIF) procedure through use of the total score as the matching variable (thin) and forming the matching variable by pooling total score levels (thick) were compared in a Monte Carlo study. Reasons thick matching is superior are discussed. (SLD)

Reevaluates statistical studies by G. Galster (1986, 1987, 1988) and Galster and W. Keeney (1988) of segregation in housing, reanalyzing one of four model equations. The effects of discrimination are smaller than postulated previously. Direct estimates from housing discrimination surveys provide a rationale for these smaller effects. (SLD)

Analyzes effect sizes in tails of distribution of scores in Feingold's study of joint effects of gender differences in mean and variability on 28 cognitive-ability scales. Effect sizes are smaller than Feingold assumed. Evaluates joint effect of gender differences by number of males and females in extreme score ranges. (SLD)

Discusses the surprising result that the expected number of marbles of one color drawn from a set of marbles of two colors after two draws without replacement is the same as the expected number of that color marble after two draws with replacement. Presents mathematical models to help explain this phenomenon. (MDH)

Studied effects of students' use of calculators with 2 experimental forms of a university mathematics test taken by 765 and 725 college students, respectively. Calculator effects are not found for overall scores but are seen for some individual items. Analysis at the item level makes the actual impact apparent. (SLD)