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681.
682.
This article explores the macroeconomic implications of tournaments as a worker discipline device in the vein of shirking models. It is shown that, if the full exploitation of tournaments is feasible, there will be no involuntary unemployment. Thus, as far as the elimination of involuntary unemployment is concerned, tournaments can serve as a perfect substitute for the so-called "employment fee" or "bonding" scheme. An immediate corollary of this finding is that the involuntary nature of unemployment must ultimately rely upon impediments that hinder the full exploitation of tournaments. 相似文献
683.
Curtis M. Jolly Budry Bayard Richard T. Awuah Simon C. Fialor Johnathan T. Williams 《Journal of Socio》2009,38(2):280-287
This study uses a modified health belief model (HBM) within a socio-economic framework to evaluate the influence of awareness and knowledge on actions to reduce aflatoxin (AF) contamination in groundnuts (peanuts). Data were collected in 2002 through a self-administered questionnaire from a sample of 367 individuals. Socio-economic factors affecting perceptions, awareness, knowledge, and action were examined using structural equation modeling. The perceived benefits of good quality groundnuts and/or groundnut products were the most important determinants of awareness and knowledge of AF among agricultural and health professionals in Ghana. Awareness, in turn, had a significant causal effect on the professionals’ decisions to take actions to increase the level of awareness of AF in the society. Demographic factors, such as gender and level of education significantly influenced knowledge of AF and the perception of the benefits of good quality groundnut. Type of profession had a significant influence on awareness and perceived seriousness of the AF problem. Education was a significant determinant of awareness of AF in groundnuts. The study generates important information for policy decision making when considering resource allocation to reduce food contamination in developing economies. 相似文献
684.
We extend the average derivatives estimator to the case of functionally dependent regressors. We show that the proposed estimator is consistent and has a limiting normal distribution. A consistent covariance matrix estimator for the proposed estimator is provided. 相似文献
685.
A generalized negative binomial distribution is derived from the Markov Bernoulli sequence of successes and failures. We study the properties and applications of this distribution. The properties are illustrated by two examples of discrete time queueing systems. The distribution is then fitted to two data sets, the eruption record of Mt. Sangay, and a record of computer disk failure accesses. In the first case there is a strong serial dependence in the data and the generalized negative binomial provides a good fit, while in the second case, although there is a significant serial dependence, it is insufficient to justify the additional parameter of the distribution. We conclude by demonstrating the usefulness of the distribution in the field of statistical quality control. 相似文献
686.
Katie M. Edwards PhD Megan J. Murphy MS Erin C. Tansill MS Christina Myrick BA Danielle R. Probst PhD Rebecca Corsa BA 《Journal of American college health : J of ACH》2013,61(3):204-210
Abstract Objective: This study assessed the process of leaving an abusive dating relationship utilizing a qualitative design. Methods: Participants included 123 college women in abusive dating relationships who participated at the beginning and end of a 10-week academic quarter. Results: Qualitative content analyses were used to analyze the transcribed responses to an open-ended question about women's leaving processes over the interim period. A variety of categories and themes emerged for women in different stages of the leaving process, consistent with the Transtheoretical Model of Change and Investment Model. Data also underscored women's lack of acknowledgment, minimization, and normalization of abuse. Conclusions: These data demonstrate the importance of dating violence intervention and prevention programming on college campuses and offer information that may be useful to college health providers who assist women in abusive dating relationships. 相似文献
687.
This paper considers a likelihood ratio test for testing hypotheses defined by non-oblique closed convex cones, satisfying the so called iteration projection property, in a set of k normal means. We obtain the critical values of the test using the Chi-Bar-Squared distribution. The obtuse cones are introduced as a particular class of cones which are non-oblique with every one of their faces. Examples with the simple tree order cone and the total order cone are given to illustrate the results. 相似文献
688.
This article outlines the structure of a generalized family of two-stage chain sampling plans, extending the concept of two-stage chain sampling plans of Dodge and Stephens (1966) which is an extension of the original work of Dodge (1955). Expressions are derived for the OC curves for two-stage chain sampling plans with (c1,c2) = (0,2) and (1,2). In the original work of Dodge (1955) only acceptance numbers of 0,1 were used and in the extension work of Dodge and Stephens (1966) acceptance numbers of (c1,c2) = (0,1), (0,2), (1,2), (0,3), (1,3), (0,4) and (1,4) were used with selected sets of values of k1 and k2 (the number of lots considered for cumulation in the first and second stage respectively). In this paper the OC curves are derived more generally for any k1 and k2combination for two-stage chain sampling plans with (c1,c2) = (0,2) and (1,2) and comparisons are made with respect to sample sizes and discriminating power, with the corresponding single and double sampling plans. 相似文献
689.
Response surface methodology is widely used for developing, improving, and optimizing processes in various fields. In this article, we present a method for constructing three-level designs in order to explore and optimize response surfaces combining orthogonal arrays and covering arrays in a particular manner. The produced designs achieve the properties of rotatability, predictive performance and efficiency for the estimation of a second-order model. 相似文献
690.