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941.
942.
Egmar Rödel 《Statistics》2013,47(3):387-397
Let Xbe a bivariate exponential-type random vector (BIDLIKAR, PATIL (1968)), than it is proved:

1. If P(X ≥0) = 1 is valid, then Xhas linear regression to both directions if and only if Xpossesses a symmetric Γ-distribution.

2. Xpossesses linear regression to both directions with constant regression coefficients (independent of the parameter vector ? of the exponential-type distribution (BIDLIKAR, PATIL (1968)) if and only if Xis normal distributed.  相似文献   
943.
944.
Abstract

Objective: This study explored the potential relationships between existing media and health apps for health information among college students. Participants: This study collected and analyzed a total of 408 surveys from students of 7 universities across the United States. Methods: In order to explore the research questions and test the hypotheses, quantitative data from the online survey were analyzed through hierarchical regression analyses. Results: Results from the hierarchical regression analyses indicated that the perceived credibility of health information from traditional mass media was positively and significantly associated with college students' perception of health apps. However, there was no significant effect in regards to online media. Conclusions: This study's consideration of the relationships between existing media and health apps may guide health practitioners in their strategic approaches to improve the well-being of college students.  相似文献   
945.
946.

Three basic sociological distinctions—viewing the environment as home or place of sustenance, separation of home and workplace, and “thing” work versus “people” work—are used to illuminate such sociological concerns as environmental degradation as a social problem, social specialization and pollution, and the demographic profiles of environmentally concerned people.  相似文献   
947.
This paper utilizes the results of Kruskal (1968), Zyskind (1967), and more recently Milliken and Albohali (1984) to derive a simple necessary and sufficient condition for 3SLS to be equivalent to 2SLS. This condition depends upon the inverse of the variance:covariance matrix of the disturbances, and the set of second stage regressors of each structural equation. More importantly, this condition should prove useful for econometric students and provides an easy method for checking sufficiency.  相似文献   
948.
In this paper we study the sampling properties of a test statistic which has important applications in the area of linear stochastic control systems with multi-inputs and multi-outputs. The statistic is the ratio of a partial sum of the eigenvalues of a sample covariance matrix and its trace. It turns out that using a method due to Sugiura we may derive a useful approximation for its distribution up to and including terms of order l/n, where n denotes the appropriate size. Numerical illustrations using real data are given.  相似文献   
949.
950.
We describe the summative assessment of role-play scenarios that we previously developed to teach central topics in the responsible conduct of research (RCR) to graduate students in science and engineering. Interviews with role-play participants, with participants in a case discussion training session, and with untrained students suggested that role-playing might promote a deeper appreciation of RCR by shifting the focus away from wanting to simply “know the rules.” We also present the results of a think-aloud case analysis study and describe the development of a behaviorally-anchored rating scale (BARS) to assess participants' case analysis performance.  相似文献   
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