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721.
S.A. Shaban 《统计学通讯:理论与方法》2013,42(14):1389-1399
Recursion relations suitable for rapid computation are derived for the probabilities of the compound Poisson distribution when the compounder is the inverse-Gaussian distribution. Series representation of the probabilities are given. Asymptotic results as well as approximations for probabilities, compared with the exact values, are investigated. 相似文献
722.
723.
Rolffs S. Pinkerton Ph.D. W. J. Kenneth Rockwell M.D. 《Journal of American college health : J of ACH》2013,61(4):159-162
Abstract One or two session psychotherapy has a long history, and well-known practitioners have made use of it. Favorable results have been reasonably well documented. Often it has been done out of necessity, less frequently because all were satisfied that it sufficed. Problems that lend themselves to one or two sessions are: psychological work which has already been done but for which affirmation is sought, requests for diagnostic evaluation, and less often but more challenging, intrapsychic conflict requiring uncovering work. Patient characteristics and therapist attitudes are discussed. For one or two sessions of treatment to occur the therapist must be alert to the possibility, must assess quickly when a case is in hand, set the process in motion, and determine a satisfactory stopping point. It is suggested that the college population lends itself especially well to one or two sessions of psychotherapy, not only from the standpoint of the limited resources of many student health services but also for the ego strengthening potential it provides. 相似文献
724.
Building on recent European studies, we used the Survey of Income and Program Participation to provide the first analysis of fertility differences between groups of US college graduates by their undergraduate field of study. We used multilevel event-history models to investigate possible institutional and selection mechanisms linking field of study to delayed fertility and childlessness. The results are consistent with those found for Europe in showing an overall difference of 10 percentage points between levels of childlessness across fields, with the lowest levels occurring for women in health and education, intermediate levels for women in science and technology, and the highest levels for women in arts and social sciences. The mediating roles of the following field characteristics were assessed: motherhood employment penalties; percentage of men; family attitudes; and marriage patterns. Childlessness was higher among women in fields with a moderate representation of men, less traditional family attitudes, and late age at first marriage. 相似文献
725.
Lot resubmissions are allowed in situations where the original inspection results are suspected or when the supplier is allowed to opt for resampling as per the provisions of the contract etc. This paper examines the situation of resampling of lots and derives the performance measures of a resampling scheme having a single sampling plan for inspection. The usefulness and limitations of resampling of resubmitted lots are also discussed 相似文献
726.
Abstract The present study examines the stability of bright light circadian readjustment during two consecutive dim light night-work periods and circadian synchronization during the recovery after a night-shift period. A sample of 10 subjects was divided into 2 groups (control group: 6 subjects; experimental group: 4 subjects). All subjects worked during 5 days, between 23:00 and 07:00 h and then went to sleep. Subjects received 2500-3000 lux between 02:00 and 05:00 h during 5 days for the control group and 3 days for the experimental group. During recovery after the night-shift periods, three cycles of bright light were administered at two different times: 12:00-15:00 h for two of six subjects from the control group and 10:00-13:00 h for all subjects (4) of the experimental group. By the fifth cycle of night-work the maximum of urinary aMT6s excretion that occurs at 05:00 h in the baseline condition was shifted to 12:00 h for the control and experimental groups (delay in hours: 7±1.6 (control); 7±1 (experimental)). This result suggests that three cycles of bright light are sufficient to induce a significant phase delay and that this delay remained stable when night-work proceeded under dim light. The phase delay of the circadian aMT6s excretion by exposure to bright light was accompanied by an improvement of the quality of day sleep and level of cognitive and psychomotor performances for control and experimental groups. No significant difference was observed in the two groups for daytime sleep and nocturnal performance. The two bright light periods used during the three days of recovery induced a complete synchronization in five of six subjects. One subject showed a partial synchronization probably because he remained at the laboratory under dim light during the day and had few family and social contacts. 相似文献
727.
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
728.
K.S. Madhava Rao 《统计学通讯:理论与方法》2013,42(12):4559-4568
Nonparametric test statistics are constructed by considering the medians in subsamples of appropriate size taken -from n independent observations. These tests are shown to be sensitive to both heavy and moderate tailed distributions. 相似文献
729.
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
730.
Jon E. Grant JD MD MPH Brian L. Odlaug MPH Katherine Derbyshire BS Liana R. N. Schreiber BA Katherine Lust PhD MPH Gary Christenson MD 《Journal of American college health : J of ACH》2013,61(1):75-78
Abstract Objective: This study examined the prevalence of mental health disorders and their clinical correlates in a university sample of lesbian, gay, bisexual, and queer (LGBQ) students. Participants: College students at a large public university. Methods: An anonymous, voluntary survey was distributed via random e-mail generation to university students during April and May of 2011. LGBQ students were compared with their heterosexual counterparts on psychological and physical status as well as academic performance. Results: LGBQ students reported worse depressive symptoms, higher levels of perceived stress, considered themselves less attractive, and were more likely to be overweight. LGBQ students were significantly more likely to report histories of affective, substance use, and certain anxiety disorders as well as compulsive sexual behavior and compulsive buying. Conclusions: The higher rates of many psychiatric conditions among LGBQ students underscore the need for universities to provide LGBQ students a nonjudgmental environment to discuss sexual orientation and health issues. 相似文献