This paper estimates the effects of various college qualities on several early adult outcomes, using panel data from the National Education Longitudinal Study. I compare the results using ordinary least squares with three alternative methods of estimation, including instrumental variables, and the methods used by Dale and Krueger [(2002).…

This article describes the sequence alignment problem in bioinformatics. Through examples, we formulate sequence alignment as an optimization problem and show how to compute the optimal alignment with dynamic programming. The examples and sample exercises have been used by the author in a specialized course in bioinformatics, but could be adapted…

In 1897, about half of all American municipalities used lead pipes to distribute water. Employing data from Massachusetts, this paper compares infant death rates in cities that used lead water pipes to rates in cities that used nonlead pipes. In the average town in 1900, the use of lead pipes increased infant mortality by 25 to 50 percent.…

The purpose of this research was to examine the effects of missing data on person-model fit and person trait estimation in tests with dichotomous items. Under the missing-completely-at-random framework, four missing data treatment techniques were investigated including pairwise deletion, coding missing responses as incorrect, hotdeck imputation,…

Purpose: The purpose of this study was to estimate hospital and long-term-care costs resulting from falls in long-term-care facilities (LTCFs). Design and Methods: The study used a retrospective, pre/post with comparison group design. We used matching, based on propensity scores, to control for baseline differences between fallers and non-fallers.…

The Kronig-Penney problem is a textbook example for discussing band dispersions and band gap formation in periodic layered media. For example, in photonic crystals, the behaviour of bands next to the band edges is important for further discussions of such effects as inhibited light emission, slow light and negative index of refraction. However,…

The mathematics curriculum in the United Kingdom (UK) has undergone radical changes, placing a particular focus on mental computation. Pupils are not taught written methods of computation until they are able to add and subtract any pair of two digit numbers mentally. Teacher education programmes in the UK have required adaptation to reflect these…

This paper describes a computational exercise at undergraduate level that demonstrates the employment of Monte Carlo simulation to study the conformational statistics of flexible polymer chains, and to predict solution properties. Three simple chain models, including excluded volume interactions, have been implemented in a public-domain computer…

The present study investigated the impact of reinforcement valence and magnitude on response timing in children with ADHD. Children were required to estimate a 1-s interval, and both the median response time (response tendency) and the intrasubject-variability (response stability) were investigated. In addition, heart rate and skin conductance…

D. von Winterfeldt, N.-K. Chung, R. D. Luce, and Y. Cho (see record 1997-03378-008) provided several tests for consequence monotonicity of choice or judgment, using certainty equivalents of gambles. The authors reaxiomatized consequence monotonicity in a probabilistic framework and reanalyzed von Winterfeldt et al.'s main experiment via a…

This article proposes an item response model that incorporates response time. A parameter estimation procedure using the EM algorithm is developed. The procedure is evaluated with both real and simulated test data. The results suggest that the estimation procedure works well in estimating model parameters. By using response time data, estimation…

In this note Scott's result is generalized and a method given to factorize separable-variable functions.

Interest in students who exhibit characteristics with difficulties in learning can be traced as far back as 1800. In order to better understand the complexities and causes of learning disabilities, many researchers (Bannatyne, 1968, 1974; Rugal, 1974) have investigated ways to better identify learners who struggle with academics. A strong argument…

Reforming teacher tenure is an idea that appears to be gaining traction with the underlying assumption being that one can infer to a reasonable degree how well a teacher will perform over her career based on estimates of her early-career effectiveness. Here we explore the potential for using value-added models to estimate performance and inform…

The purpose of this study was to determine the effects of an early numeracy preventative Tier 2 intervention on the mathematics performance of first-grade students with mathematics difficulties. Researchers used a pretest-posttest control group design with randomized assignment of 139 students to the Tier 2 treatment condition and 65 students to…