Education systems are increasingly creating rich, longitudinal data sets with frequent, and even real-time, data updates of many student measures, including daily attendance, homework submissions, and exam scores. These data sets provide an opportunity for district and school staff members to move beyond an indicators-based approach and instead…

Causal reasoning represents one of the most basic and important cognitive processes that underpin all higher-order activities, such as conceptual understanding and problem solving. Hume called causality the "cement of the universe" [Hume (1739/2000). Causal reasoning is required for making predictions, drawing implications and…

This rejoinder to McCall (Volume 56, 217-218) discusses the differences in viewpoint with respect to the relationship between models and theory, the notion of "direct" tests of propositions, and the use of measures of explained variance to evaluate model performance. (Author/BE)

Proposes a probabilistic mechanism to describe various forms of the Bradford phenomenon reported in bibliographic research. The inclusion of a time parameter in the model to allow predictions of dynamic systems is explained. (58 references) (CLB)

Regression models were developed for predicting internal and external turnaround time for interlibrary loan requests. Variables included document characteristics (publication age, language, document type, and subject); request characteristics (patron type, staffing levels, number of daily requests, and number of concurrent requests from a patron);…

The 21 essays in this two-part book provide conceptual and operational understanding of the nature of models as representations of reality and as tools for description, analysis, interpretation, and forecasting. Topic areas addressed in part 1 (concept) include: the nature of models; the earth as a system; the determination of form; some…

Argues that library book circulation is a binomial rather than a Poisson process, and that individual book popularities are continuous beta distributions. Three examples demonstrate the superiority of beta over negative binomial distribution, and it is suggested that a bivariate-binomial process would be helpful in predicting future book…

Estimates confluence model of intellectual development for a within-family sample of 321 children from 101 transracial adoptive families. Mental ages of children and their parents and birth or adoption intervals were used in a nonlinear least-squares estimation procedure to obtain children's predicted mental ages. Results suggest efficiency of the…

A modal model of information processing was defined, and nine tasks that could be completed by persons with mental retardation were developed to operationalize the model. Results showed that individual differences in higher mental processes are highly dependent on basic cognitive abilities and can be predicted from them. (Author/JDD)

This article responds to commentaries (EC 604 996-998) on a paper by Douglas Detterman and others (EC 604 995), which developed and tested a modal model, with young adults with and without mental retardation as subjects, to assess basic cognitive abilities in relation to cognitive deficits. (JDD)

Seven techniques for measuring information processing in infants are proposed to aid in the early identification of mental retardation. The techniques are based on conditioning, attentional, and manual exploration paradigms and could be combined into an assessment battery more valid than current infant IQ tests in predicting later disability.…

This exploratory resource allocation model for implementing community-based supported employment services for persons with mental retardation uses a multivariate linear regression approach to project the hours required to develop a job site based on the size of the community, the rate of unemployment, and the percent of service jobs. (Author/DB)

Using data collected in 95 Ohio school districts by Brock Hunt, this study reanalyzed those data, examined the reasons for Hunt's inability to predict a school board member incumbent's defeat, and developed a model that would have predicted those Ohio school board elections. Hunt attempted to develop a statistical model of socioeconomic-political…

Examines a statistical model in which the users of an online system continually update their estimated probability of success, and quit or continue the search according to the expected utility of each action. The implications for search strategies are discussed. (Author/EM)

Describes a sustainable planet index (SPI) to gauge the survivability of the earth ecologically and economically. Compares the SPI to the consumer price index and general business cycle theory from which it draws constructs. Suggests that the SPI exhibits properties of a sine wave and is useable in mathematical formulations, explanation, and…