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981.
982.
983.
The college student-athlete: psychological considerations and interventions   总被引:1,自引:0,他引:1  
This article reviews the literature dealing with problems brought by student-athletes to college counseling and mental health centers. Among the issues discussed are fear of success; identity conflict; social isolation; poor athletic performance; academic problems; and career or vocational concerns. In addition, the authors examine the paradox that although athletes experience as much or more psychological distress as nonathletes, research indicates that athletes use professional services less often than nonathletes. Finally, the authors review approaches to psychological intervention, including short-term psychotherapy, very brief interventions, cognitive behavioral therapy, and career/vocational counseling, and discuss special considerations for conducting therapy with athletes.  相似文献   
984.
In assessing the influence of regional Environmental Protection Agency EPA offices on the state management of hazardous waste programs, we focused on the extent to which federal administrative decisions affect levels of enforcement activity by state environmental agencies and whether these effects vary over time. Our results indicated that state enforcement actions were affected by state program capacity variables such as primacy and the strength of existing hazardous waste policies as well as one federal-level factor—the distribution of grant monies. The impact of federal oversight decisions was minimal.  相似文献   
985.
Lehmann & Stein (1948) proved the existence of non-similar tests which can be more powerful than best similar tests. They used Student's problem of testing for a non-zero mean given a random sample from the normal distribution with unknown variance as an example. This raises the question: should we use a non-similar test instead of Student's t test? Questions like this can be answered by comparing the power of the test with the power envelope. This paper discusses the difficulties involved in computing power envelopes. It reports an empirical comparison of the power of the t test and the power envelope and finds that the two are almost identical especially for sample sizes greater than 20. These findings suggest that, as well as being uniformly most powerful (UMP) within the class of similar tests, Student's t test is approximately UMP within the class of all tests. For practical purposes it might also be regarded as UMP when moderate or large sample sizes are involved.  相似文献   
986.
In light of the Armitage-Doll multistage carcinogenesis theory, this paper examines the assumption that an additive relative risk relationship is indicative of two carcinogens that affect the same stage in the cancer process. We present formulas to compute excess cancer risks for a variety of patterns for limited exposure durations to two carcinogens that affect the first and penultimate stages; and using an index of synergy proposed by Thomas (1982), we find a number of these patterns to produce additive, or nearly additive, relative risk relationships. The consistent feature of these patterns is that the two exposure periods are of short duration and occur close together.  相似文献   
987.
This commentary discusses the articles in the special section, “Adolescent Career Development in Social Context.” Initially, common and integrative themes are identified and explicated based on the diverse perspectives of the work role in adolescence that were evident in these five articles. In addition, the theoretical frameworks provided by life-span, career development relational perspectives are discussed as possible means of integrating some of the findings presented by the authors of these articles. This article concludes with an observation on how the findings reported in the special section can inform career development scholarship and practice in the next millennium.  相似文献   
988.
This paper presents a limited assessment of the conservatism of the Accident Sequence Evaluation Program (ASEP) human reliability analysis (HRA) procedure described in NUREG/CR-4772. The data for this study are derived from simulator examination reports from the NRC requalification examination cycle for nuclear power plant operators. The ASEP procedure was used to estimate human error probability (HEP) values for critical tasks, and the HEP results were compared with the failure rates observed in the examinations. The ASEP procedure was applied by PNNL operator license examiners who supplemented the limited information in the examination reports with expert judgment based upon their extensive simulator examination experience. Comparison of the average of the ASEP HEP values with the fraction of the population actually failed and demonstrated that the ASEP HEP values are larger (conservative) by a statistically significant average factor of two. Partitioning of tasks into subgroups based on the ASEP HEP values and comparison of the subgroup average ASEP HEP values with observed subgroup failure rates showed little or no conservatism for small ASEP HEP values, but considerable conservatism for larger ASEP HEP values.  相似文献   
989.
Outsourcing and union power   总被引:1,自引:0,他引:1  
The outsourcing of union work and jobs either diffuses or diminishes union membership, depending on perspective and situation. The correlation of trends in union membership to trends in union power, while less than perfect, has until recently been relatively strong over the past sixteen years. The fact that as diverse a sample of unions as AFSCME, SEIU, and UAW have chosen to make outsourcing a prominent labor/public relations issue suggests that the correlation continues to be perceived by the union movement to be significant, notwithstanding the efforts of the “new” leadership of the AFL-CIO to break that link with respect to union political power by “taxing” member unions and their members to contribute both money and militancy to the 1996 election cycle. Although outsourcing may lead only to the diffusion of union membership either within or between unions, as opposed to the diminution of union membership, this fact has not received a great deal of attention. The net effect on total union membership of outsourcing from one union employer to another union employer is unclear, although the effect on the membership of the union at the outsourcing employer is not. The redistribution of membership within a union as a result of outsourcing is likely to have little immediate impact on union power. However, as even the best case scenario presented above suggests, it may have significant long-run deleterious effects on union bargaining power by taking labor out of a sheltered market and putting it into potentially competitive market. This is particularly likely to be the case when outsourcing (1) places the outsourced work into a different industry or wage contour and (2) creates the possibility of moving from sole-source to multiplesource supplier arrangements. The redistribution of membership between unions as a result of outsourcing is unlikely to have a major impact on union power broadly defined. It can have, however, serious deleterious effects in terms of the power of an individual union, as suggested in my “competitive case” scenario. The fact that one union’s losses due to outsourcing may be another union’s gain is of little consolation to the losing union. That act, in and of itself, may make the threat of outsourcing a potential union “Achilles heel” at the bargaining table by placing it into competition with some other, perhaps unknown, union as well as possibly nonunion competition. The most obvious threat to union power comes from outsourcing that diminishes union membership overall by transferring jobs from union to nonunion employers. The willingness and ability of employers to move work/jobs entirely out of the orbit of union control constitutes, in terms of power and particularly union bargaining power, a revisitation of the phenomenon of the “runaway shop.” It may also be viewed as a proactive form of hiring permanent replacements for (potentially) striking workers. The union options in dealing with such a challenge are to endeavor to preclude outsourcing through legislation or collective bargaining or to chase the work by organizing the unorganized, hopefully with the help of the unionized outsourcing employer. Neither option may be easy, but as the 1996 auto industry negotiations suggest, the former may be less difficult than the latter. The possibility that outsourcing from union to nonunion employer may provide unions with the power to organize from the top (outsourcer) down (outsourcee) cannot be entirely ignored as the issue of supplier “neutrality” reportedly was raised in the 1996 auto negotiations. The adverse effects of outsourcing on union political and financial power, by virtue of its impact on the level or distribution of union membership, can and may well be offset by an increase in union activism—as measured by dues levels, merger activity, organizing commitment, and political action. The adverse effects of outsourcing on union bargaining power are more problematical from the union standpoint. The effect of outsourcing, whatever its rationale or scenario, appears to be to put union labor back into competition. Thus, outsourcing constitutes yet another challenge to the labor movement in its ongoing and seemingly increasingly unsuccessful battle to take and keep U.S. union labor out of competition by proving itself able and willing to organize to the extent of the market and standardizing wages in that market.  相似文献   
990.
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