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901.
I discuss the recent proliferation of mandatory project labor agreements in government procurement, some of the ensuing litigation, and the effects of such agreements on contractors, workers, and the public.  相似文献   
902.
Ostland  M.  Yu  B. 《Statistics and Computing》1997,7(4):217-228
We first review quasi Monte Carlo (QMC) integration for approximating integrals, which we believe is a useful tool often overlooked by statistics researchers. We then present a manually-adaptive extension of QMC for approximating marginal densities when the joint density is known up to a normalization constant. Randomization and a batch-wise approach involving (0,s)-sequences are the cornerstones of our method. By incorporating a variety of graphical diagnostics the method allows the user to adaptively allocate points for joint density function evaluations. Through intelligent allocation of resources to different regions of the marginal space, the method can quickly produce reliable marginal density approximations in moderate dimensions. We demonstrate by examples that adaptive QMC can be a viable alternative to the Metropolis algorithm.  相似文献   
903.
Empirical research with regard to the Protestantethic is reviewed in relation to Weber s model of thepart a specifically religious ethos played in the riseof capitalism. Weber argued that Western legal and commercial changes were not in themselvesan adequate explanation. Essential also was the set ofvalues emphasized by ascetic Protestantism:self-discipline, hard work, the careful use of time, the reinvestment of one s gains, personal honesty,creative innovation, and faith in the rewards of a justGod. Empirical research has found positive correlationsbetween Protestant ethic values and internal locus of control (self-discipline), hard work,honesty, and belief in a just world. Findings withregard to the use of time and money are inconclusive.The relationship with creative innovation has not been examined. There is a need for empiricalstudy of the relationship between the Protestant ethicand personal religious orientation.  相似文献   
904.
SUMMARY Invoking the predictive approach with a fixed population set-up, and employing initially the customary ratio and product estimators as potential predictors for the non-surveyed part of the population, we have generated sequences of ratio-based and product-based estimators. The proposed ratio-based and product-based estimators of order k are-under some practical conditions-found to be more efficient than the customary ratio and product estimators and the usual simple mean when k is chosen optimally. Under the optimal value of k, the kth-order ratio-based and product-based estimators are found to be as efficient as the linear regression estimator. We have used real population data to illustrate the efficacy of the proposed ratio-based and product-based estimators relative to the usual simple mean and the customary ratio and product estimators.  相似文献   
905.
Pericchi and Smith considered a normal location parameter problem with double-exponential and Student t prior distributions. These two prior distributions both belong to the class of scale mixtures of normal distributions and are useful in providing a robust analysis of the normal location parameter problem. In this paper we extend the analysis to other scale mixtures of normal distributions, such as the exponential power and the symmetric stable distributions.  相似文献   
906.
Although estimates concerning the prevalence of various forms of substance abuse vary considerably, it is critical to note that even the more conservative estimates indicate a major public health problem. Furthermore, increased drug experimentation has been frequently associated with the college experience. Utilizing a slightly modified version of the National Institute on Drug Abuse (NIDA) Monitoring the Future Survey, the present study examined the epidemiology of self-reported drug taking behaviors (e.g., alcohol, marijuana, tranquilizers, stimulants, psychedelics, etc.) among a sample (n = 683) of students attending a major public university. Data analyses focused on the specific settings and social groupings in which drug use occurred as well as on the frequency and type(s) of drug taking behaviors. Based on the results yielded from a disjoint cluster analysis, four distinct groups of drug users were identified. These four groups then served as categories of the dependent variable in a discriminant function analysis. A general linear models procedure was employed to identify the more efficacious discriminating (i.e., independent) variables.  相似文献   
907.
This study examined the effect of probing for additional information on the accuracy of deception detection. One hundred forty-eight experimental interactions were analyzed to see whether deceivers and truthtellers behave differently when probed and whether probing improved deception detection. Probing produced a number of changes in nonverbal behavior, several of which differed between deceivers and truthtellers. Probing may have communicated suspicion or uncertainty; therefore, deceptive sources were motivated to control their nonverbal demeanor to mask deception-related cues and appear truthful. Probing did not improve detection. Instead, probing receivers considered all sources more truthful. It is suggested that suspiciousness and prior knowledge may affect probing's efficacy.  相似文献   
908.
Nonverbal expectancy violations and conversational involvement   总被引:1,自引:0,他引:1  
A central feature of nonverbal expectancy violations theory is that unexpected behaviors trigger a cognitive-affective appraisal of such behavior, leading to a valencing of the behavior(s) as positive or negative. It has been proposed that communicator reward mediates the interpretation and evaluation of such violations but may be more important when the violative act is ambiguous in meaning than when it is not. Unclear is whether nonverbal behavioral composites introduce greater or less equivocality of interpretation. Two experiments employing multi-cue conversational involvement violations addressed this issue. In the first, dyads (N=51) engaged in a 10-minute baseline interview, after which participants rated each other on several measures of reward valence. One randomly selected member then served as a confederate interviewee during a second interview and either significantly increased or decreased involvement. In the second experiment, reward was manipulated as physical attractiveness, status, and task expertise. Dyads (N = 60) engaged in prolonged problem-solving discussions during which the confederates either committed an involvement violation or not. In both experiments, the involvement changes were sufficiently unexpected, arousing, and distracting to qualify as violations of expectations. Analysis of message interpretations indicated that (1) relative to normal involvement levels, increased nonverbal involvement was interpreted as most immediate/affectionate, receptive, similar, dominant, and composed, and decreased involvement as least so, and (2) reward mediated only the interpretation of formality. High involvement violations in turn produced greater attraction, credibility, and persuasiveness than low involvement violations for high as well as low-reward communicators, as predicted.where Joe Walther and Jim Baesler are doctoral students. An earlier version of this paper was presented to the annual meeting of the International Communication Association, New Orleans, May 1988.  相似文献   
909.
910.
This study surveyed 975 undergraduates attending a large East Coast university during the spring semester of the 1987/88 academic year. A convenience sample of predominantly black students (94%) participated. Overall, knowledge of basic AIDS-related facts was satisfactory. Raw scores on the 25-item knowledge scale ranged from 7 to 25, with a mean of 20.5 (82%) and a mode of 22 (88%). Selected questions on how HIV is not transmitted, however, posed some problems for respondents. Less than 30% of respondents knew that the AIDs virus was not transmitted by insects; less than 80% knew that AIDS was not transmitted on toilet seats, through blood donations, kissing, and coughing. The survey also asked students whether they had ever engaged in certain behaviors that put them at risk of HIV infection. Approximately 17% of respondents had experienced anal intercourse, 6.5% reported use of heroin, 32.6% reported having had multiple sex partners, and 16% had been treated for a sexually transmitted disease. Students who reported engaging in high-risk behaviors had statistically significant lower mean knowledge scores than those who reported not engaging in those same high-risk behaviors. Results of the study support the need to increase efforts to deliver AIDS information specifically targeted to individuals who may be engaged in high-risk behaviors. Special health education programs must be designed to focus attention on risk behaviors (ie, unprotected anal intercourse) instead of risk groups (ie, homosexual and bisexual males).  相似文献   
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