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1.
In this paper we consider the Neyman accuracy and the Wolfowitz accuracy of the Stein type improved confidence interval I?S for the disturbance variance in a linear regression model. The Neyman accuracy is a measure related to the unbiasedness of a confidence interval, and the Wolfowitz accuracy is related to the closeness of the endpoints to the true parameter. We show that I?S is not unbiased and give some numerical results for the Neyman accuracy. As for the Wolfowitz accuracy we derive the sufficient condition for I?S to improve on the usual confidence interval under this criterion and show numerically that a large degree of improvement can be obtainted.  相似文献   
2.
明朝正德到嘉靖年间,湛甘泉(1466-1560)在构想着"内外、心事"合一的理论时,提倡了将"德业"与"举业"统一的主张。虽然他的主张受到了当时士人的支持,王门的聂豹(1487-1563)和邹守益(1491-1562)也对它表示赞同,但他们俩尝试对其理论进行修订,提到了将内外合一的立场向内一方倾斜的看法。到嘉靖后半期,蒋信(1483-1559)和胡直(1517-1585)两人都关注着内外合一状态的实践主体与客体之间紧密关系,针对内外合一的理论尝试进一步深化。  相似文献   
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We consider bridge regression models, which can produce a sparse or non-sparse model by controlling a tuning parameter in the penalty term. A crucial part of a model building strategy is the selection of the values for adjusted parameters, such as regularization and tuning parameters. Indeed, this can be viewed as a problem in selecting and evaluating the model. We propose a Bayesian selection criterion for evaluating bridge regression models. This criterion enables us to objectively select the values of the adjusted parameters. We investigate the effectiveness of our proposed modeling strategy with some numerical examples.  相似文献   
5.
The problem of constructing classification methods based on both labeled and unlabeled data sets is considered for analyzing data with complex structures. We introduce a semi-supervised logistic discriminant model with Gaussian basis expansions. Unknown parameters included in the logistic model are estimated by regularization method along with the technique of EM algorithm. For selection of adjusted parameters, we derive a model selection criterion from Bayesian viewpoints. Numerical studies are conducted to investigate the effectiveness of our proposed modeling procedures.  相似文献   
6.
This report shows that one of the most important roles of the flower nectar of an autogamous perennialRorippa indica (L.) Hieron is as an attractant for employing some ant species as a defense against herbivorous insects. The plant has flowers from spring to early winter. Its flower nectar is frequently stolen by some ant species (hereafter cited as ants) which also feed on small herbivorous insects on the plant. Internations among the tritrophic levels (R. indica, herbivores, ants) were experimentally examined and the followings became clear. (1) Ants were attracted toR. indica in search of its flower nectar. (2) The gradual secretion of flower nectar seemed to detain ants on the plant. (3)Pieris butterfly lavae were the major herbivores onR. indica and were potentially harmful to the plant. (4) The presence of ants reduced the survival rate ofP. rapae larvae onR. indica. (5) The presence of ants reduced the feeding damage toR. indica. (6) The disadvantage of nectar use by ants seemed to be minimal for the plant since the ants did not disturb the other flower visitors. These facts suggest a mutualistic relationship betweenR. indica and ants. That is, the flower nectar serves as an indirect defense against herbivorous insects.  相似文献   
7.
Aim: To evaluate epidemiologically the association between measured prostate volume and sex hormones.

Methods: Between December 2012 and September 2014, 226 patients attending the urological clinic were assessed for the relationship between prostate volume (PV) and, serum sex hormones, physical size, personal habits, etc. Prostate volume was measured by using transabdominal ultrasonography. Statistically, the Pearson correlation coefficients test was used.

Results: Total cases, the cases of PV?≤?25?ml, and the cases of PV?>?25?ml were evaluated respectively. Total cases and the cases of PV?>?25?ml showed a positive significant correlation with testosterone (T), but the cases of PV?≤?25?ml showed no such correlation. The cases of PV?>?25?ml had a positive significant correlation with estradiol (E2), but total cases and cases of PV?≤?25?ml did not. Dehydroepiandrosterone sulfate (DHEAS) showed no correlation with any case of PV, however it decreased significantly with age and had a correlation with alopecia. The E2/T ratio had no correlation with any case of PV, but on the other hand, the T/DHEAS and E2/DHEAS ratios had significant positive correlation with PV?>?25?ml.

Conclusions: Serum T and E2 had significant positive correlation with measured PV especially in larger prostates. This result seems to correspond with the conventional theory that T and E2 have an etiological effect on benign prostatic hyperplasia. DHEAS did not show direct correlation with PV, however it appeared to suppress the role of T and E2 on benign prostatic hyperplasia growth. DHEAS might be a key to understanding the etiology of benign prostatic hyperplasia with aging.  相似文献   
8.
Child and Adolescent Social Work Journal - Gun carrying and bullying victimization are associated among adolescent boys, however the type of the bullying remains relatively unknown. This study...  相似文献   
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Matured seeds of bitter cress,Cardamine scutata Thumb, are scattered by the bursting of siliques. They also burst in response to chewing by seed predatory caterpillars even when seeds are immature. In this case, the caterpillars are frequently expelled, or killed when their bodies become enswathed by the released pericarps. Consequently, many seeds escape from the attack. The plant trait is explained as an immediate induction of a physical defense against seed predators. The germination rate of scattered immature seeds was significantly lower than that of mature ones, which is a direct demonstration of trade-off between anti-herbivore defense and reproduction of the plant.  相似文献   
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