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181.
This article examines judicial and administrative rulings and legislation involving or related to the issue of drug testing in the workplace. It discusses the rights of employees in the public and private sector: constitutional rights; federal, state, and local statutory rights; rights of unionized employees; and common law rights. It analyzes both the current state of the law and future directions the law may take, as courts and administrative agencies decide more cases and governmental bodies continue to pass drug testing legislation.  相似文献   
182.
The simulation problem is one of the most commonly used formats in computer-assisted instruction (CAI). In medical education, a patient simulation problem is known as a patient management problem (PMP). A number of computerized PMP systems are currently available. However, to date, there is no record of PMP systems having been developed using artificial intelligence. This is noteworthy since artificial intelligence techniques could help in the generation of more effective and intelligent instructional systems.

This paper analyzes and evaluates existing instructional simulation software in clinical medicine in terms of effective educational design attributes. Components of effective PMP systems thus identified are incorporated into a computerized instructional system which uses artificial intelligence techniques for teaching problem-solving and diagnostic skills to undergraduate medical students.  相似文献   

183.
Polyhedral combinatorics is a subarea of combinatorial optimization of increasing practical importance. It deals with the application of the theory of linear systems and linear algebra to combinatorial problems. The paper is not intended as a survey on polyhedral combinatorics but it reviews some of the main concepts and proof techniques.  相似文献   
184.
Distribution-free tests for comparing several treatments with a control   总被引:1,自引:0,他引:1  
Abstract  In this paper we propose distribution-free treatments versus control tests for the one- and two-way classifications. The null distribution properties are shown to be equivalent to those of well-known statistics for which critical values have been extensively tabled. Asymptotic relative efficiencies with respect to corresponding normal theory competitors are derived and optimal designs for the allocation of experimental units to the treatments and control are obtained.  相似文献   
185.
Summary In this paper it is investigated whether robust estimation procedures for the parameters of a regression model are also applicable when the observations are generated by the errors-in-variables model. Specifically, attention is paid to bounded-influence estimators, i.e. estimators that are constructed in such a way that the influence of a single observation on the outcome of the estimator is bounded. Both the classical errors-in-variables model and models with contaminated observational errors are considered.The authors are indebted to a referee for his valuable comments on an earlier version of this paper.  相似文献   
186.
Summary The problem of estimating the slope of a linear relationship between two jointly normally distributed random variables is considered when outliers may occur in the explanatory variable. It will be studied as a special case of an errors-in-variables problem where the explanatory variable is measured which a nonnormally distributed error. In this more general model and under certain conditions a consistent estimator can be given with a normal limiting distribution. Applications to cases of outliers in the explanatory variable will be presented.  相似文献   
187.
The purpose of this study was to (a) compare the occupational sex stereotypes of 366 college students with those reported by Shinar in 1975, and (b) examine the relationships between demographic, experiential, and attitudinal variables and these occupational sex stereotypes. The results indicated a significant difference in occupational ratings from Shinar's study, with females' perceptions shifting more than males' perceptions. In addition, subjects' gender, tenure with female managers, and attitudes toward women as managers, were shown to be significant predictors of occuptational ratings. The implications of these findings for both employees and managers are then discussed.  相似文献   
188.
A bstract . The spirit of capitalism arose not from a change in religion, as Max Weber claims, but from a break in the philosophic tradition that was initiated by Machiavelli , whose economic consequences were spelled out by the Neapolitan Antonio Serra in a path breaking treatise of 1613. Serra called for an active government promoting manufacturing enterprises that would enjoy ever advancing technology and indefinite declines in unit costs. A newly-structured market economy would guarantee an ever-growing consumer basket in an acquisitive system centered in self advantage, national and individual, pursued in independence of traditional moral restraints on avarice. Writing in jail, Serra advances his new and anti-scholastic ideas with great discretion for fear of persecution by political and ecclesiastical authorities who were, at the time, against innovation of all kinds.  相似文献   
189.
This paper develops two new nonparametric tests for optimizing behavior in production. The first is a test for consistency of observed data with cost minimization from a superadditive technology. Superadditivity of technology plays a key role in the theory of industry structure and natural monopoly. The second is an extension of Varian's profit maximization test. When the data fails Varian's test, one possible explanation is technical/allocative inefficiency. However, another possibility is the presence of unobservable, untradeable, and varying endowments of some factor of production. This paper develops a test that allows for such an ordinally measurable factor and notes its correspondence to the Afriat Theorem for utility maximization in demand analysis.The refereeing process of this paper was handled through R. Banker.  相似文献   
190.
There is an increasing realization, world‐wide and in Southern Africa, that conservation and development are compatible.

Because human communities in the less developed rural areas are dependent on a renewable group of resources, including soil, water and forests, it is imperative that land use systems that protect these resources are introduced.

The predominance of subsistence agriculture in these areas is the most difficult syndrome of under‐development. An overall rural development strategy is required that integrates human development with resources management Where the population carrying capacity of the land has already been exceeded, a process of rapid villagization/urbanization is required. Village/urban growth and agricultural development require a carefully co‐ordinated programme of land capability analysis and planning, as well as active investment in infrastructure and the introduction of appropriate technologies and institutions.  相似文献   

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