This paper reports on studies of the deterministic and stochastic behaviours of a predator-prey system with prey-dependent response function. The first part of the paper deals with the deterministic analysis of uniform boundedness, permanence, stability and bifurcation. In the second part the reproductive and mortality factors of the prey and…

The G index is a measure of the similarity between individuals over dichotomous items. Some tests for the G-index are described. For each case an example is included. (Author/GK)

Estimates a college-attendance equation for a common set of students (from the High School and Beyond Survey) using three popular econometric specifications: the multinomial logit, the ordered probit, and the bivariate probit. Estimated marginal effects do not differ significantly across the three specifications. Choice of specification may not…

The average citation per article in chemistry by age of citation is related to the Poisson frequency distribution. This provides a formula for calculation of a half-life for chemistry which depends on the structure of the research front exhibited in the literature. (Author/FM)

In 1984 "Economics of Education Review" paper, E. Bell indicates that, when capital markets are imperfect in a certain sense, demand for education may not always be directly related with present net value of education. This study shows Bell's paradox is possible under the alternative definitions of capital market imperfections and…

Explores whether flexible nonlinear models (including neural networks and genetic algorithms) can reveal otherwise unexpected patterns of relationship in typical school-productivity data. Applying three types of algorithms alongside regression modeling to school-level data in 183 elementary schools proves the hypothesis and reveals new directions…

Examines data from California from the 1850 opening of the prison system to 1970. Finds no evidence to support the hypothesis that, for a given society over time and in the absence of major societal upheaval, the proportion of people subjected to punishment by the state closely approximates a constant. (Author/GC)

Analyzes propensity of business school alumni to give cash donations to their alma mater. Estimates a utility maximization model, using logistic regression and survey sample data of 1956-90 graduates of a large U.S public research university. Giving probability is strongly correlated with specific majors, time since graduation, other factors.…

The primary objective of this paper is to describe a method of estimating female-male wage ratios. The estimating technique presented is two stage least squares (2SLS), in which equations are estimated for both men and women. After specifying and estimating the wage equations, the male-female wage differential is calculated that would remain if…

Learning processes have been investigated for regularities of the changes in the strength of a reflex that result from manipulations of several parameters of a stimulus. Most of this work has been carried out in the tradition of associative theory. One consequence of this emphasis was that for a long time several phenomena that can be…

Results from numerous school- and teacher-effectiveness studies suggest that variation between classes is more significant than variation between schools, though evidence often seems contradictory. This article considers why different studies generate different findings, identifies key study design issues, and relates these observations to…

Applies neural network methods for forecasting 1991-95 per-pupil expenditures in U.S. public elementary and secondary schools. Forecasting models included the National Center for Education Statistics' multivariate regression model and three neural architectures. Regarding prediction accuracy, neural network results were comparable or superior to…

Focuses on a specific federal credit program (the guaranteed student loan program), using the Engle and Granger two-step procedure to estimate an error correction model of commercial student loan supply. Results indicate that the secondary market is an important determinant of commercial student loan lending and that commercial supply is inelastic…

Describes how to employ multivariate regression models and National Research Council data (used to rank doctoral programs) to analyze how measures of program size, faculty seniority, and faculty research and doctoral-degree productivity influence subjective ratings of doctoral programs in 35 academic fields. Illustrates how to compute the effects…

The first step of the data analysis with respect to the eventual application of the various new methods in latent trait theory is here initiated. The data are a set of approximately 500 item responses of each of 7,439 examinees to the Iowa Tests of Basic Skills, Form 6, on one of three difficulty levels, which correspond to the ages of 11, 12 and…