The union-intersection principle applied to the test of dimensionality

In the first section Anderson-Rao-Fujikoshi's test statistics for testing the hypothesis of dimensionality are reviewed and then Olkin-Tomsky's generalized union-intersection principle is applied to show that a new class of test statistics for testing the hypothesis of dimensionality are derived which includes the likelihood ratio test statistics, the trace test statistics and a version of ROY'S maximum root test statistics.     

Community-Based System,Reports, and Substantiated Cases of Elder Abuse: Disparities Between Municipalities and Relating Factors in Japan

This study examines (1) the staffing and financial characteristics of systems for elder abuse detection and intervention in the municipal governments of Japan and (2) the relationship among the development of detection and intervention systems, the reporting rates of suspected elder abuse cases, and substantiated abuse rates in 927 municipalities across Japan. Progressive systems for the detection and intervention of elder abuse were significantly associated with a larger number of public officers than in non-progressive systems. Furthermore, greater rates of both suspected and substantiated cases of abuse were associated with progressive systems for elder abuse detection and intervention. Per capita annual expenditures on the comprehensive support project and the community general support center's catchment under the Long-Term Care Insurance (LTCI) program showed no significant association with the development of systems, the rate of suspected cases, or the number of substantiated cases. National social policy makers should examine strategies that would help municipalities assign sufficient staff to elder abuse detection and intervention programs.     

Likelihood ratio test for one-sided hypothesis of covariance matrices of two normal populations

The likelihood ratio test is derived for a one-sided hypothesis about the covariance matrices from two multivariate normal populations. In the case of equal sample sizes, the limiting distribution of -21og ?_n is given, where ?_n denotes the likelihood ratio criterion. When dimension p=2, for some alternatives, the power of -21og ?_n of size 0.05 is compared with those of several well-known test statistics using Monte Carlo Methods.     

东亚合作的区域主义分析

1997年东亚经济危机揭开了东亚区域一体化的序幕,ASEAN+3框架下的金融合作极大地推动了区域合作的进程.在经济危机面前,以区域主义替代华盛顿共识下的全球标准,谋划建立地区安全体系是东亚区域合作的实质.东北亚是东亚地区最重要的次区域,这一地区内部各国间积极的经济、人员交流为推进地区合作创造了条件,但是同时也存在很多障碍.只有通过民间的交流增进相互理解和信任,达成次区域合作,才能使东亚最终走向一体化.     

Detecting a change in variances

The likelihood ratio test for testing for a change in a sequence of variances of normal populations is derived. The alternative hypothesis considered is of a one-sided nature. For the test, the conservativeness of the Sidak bound is shown and the asymptotic version of the Sidak bound is also constructed. These bound are compared with the Bonferroni bound and the Worsley bound, using the Monte Carlo method. Finally Hsu's data of stock market returns is reanalysed, using the test.     

How an ant decides to prey on or to attend aphids

The following results on the behavior decision making of the antLasius niger toward two species of myrmecophilous aphidsLachnus tropicalis andMyzocallis kuricola on chestnut trees have been found. (1) An individual worker consistently attended only one aphid species, even if her nestmates attended other aphid species on the same tree. (2) The ants preyed less on the aphid species which they attended than on other myrmecophilous aphid species. (3) The ants preyed less on the aphids which had been attended by their nestmates, even if both aphids were the same species. (4) The ants preyed less on aphids which had provided honeydew to their nestmates. (5) The increased aphid density per ant led to an increase in the rate of predation on the introduced aphids by the ants. These results suggest that each worker ofL. niger chooses aphid species to attend from her experience. In addition, the workers can recognize whether an aphid has been attended by their nestmates and whether an aphid has given their nestmates honeydew. Through these processes, each worker decides to attend or to prey on the aphid. As a result, they may realize efficient collective foraging dependent on aphid density per worker.     

Urban Space and Cyberspace: Urban Environment in the Age of Media and Information Technology

Today, the many innovations and the spread of new media and information technologies are bringing new realities to contemporary society. In Japanese sociology, this social transformation is called johoka , or information–oriented transformation. The present study examines two aspects of today's urban environment, concerning this social transformation. One is the phenomenon of "Disneylandization" of the urban environment and the other is the emergence of "cyberspace" or the "cybercity". The former is the proliferation of areas and buildings filled with signs and designs that are quoted from other historical or geographical contexts, and arranged under some "theme" or "concept", such as theme parks. The latter is the emergence of "virtual spaces" and the "virtual city" in computer networks, especially on the Internet. The former is a change in the physical urban environment and the latter is a phenomenon of the non–physical environment, inside computers. However, in spite of this contrast, these phenomena can be considered to result from the same social transformation—that is, the new relationship between space and society. The semantic emptiness, and expectations and desires for a sense of "placeness" in contemporary society are the preconditions of both phenomena. Often these elements are regarded as postmodern phenomena, yet it is of interest to explore Disneylandization and the emergence of the cybercity as the latest versions of the modern urban transformation and the modern urbanism.     

Estimation of Benchmark Dose as the Threshold Amount of Alcohol Consumption for Blood Pressure in Japanese Workers

In order to determine the threshold amount of alcohol consumption for blood pressure, we calculated the benchmark dose (BMD) of alcohol consumption and its 95% lower confidence interval (BMDL) in Japanese workers. The subjects consisted of 4,383 males and 387 females in a Japanese steel company. The target variables were systolic, diastolic, and mean arterial pressures. The effects of other potential covariates such as age and body mass index were adjusted by including these covariates in the multiple linear regression models. In male workers, BMD/BMDL for alcohol consumption (g/week) at which the probability of an adverse response was estimated to increase by 5% relative to no alcohol consumption, were 396/315 (systolic blood pressure), 321/265 (diastolic blood pressure), and 326/269 (mean arterial pressures). These values were based on significant regression coefficients of alcohol consumption. In female workers, BMD/BMDL for alcohol consumption based on insignificant regression coefficients were 693/134 (systolic blood pressure), 199/90 (diastolic blood pressure), and 267/77 (mean arterial pressure). Therefore, BMDs/BMDLs in males were more informative than those in females as there was no significant relationship between alcohol and blood pressure in females. The threshold amount of alcohol consumption determined in this study provides valuable information for preventing alcohol-induced hypertension.     

Partitioning 2-edge-colored complete multipartite graphs into monochromatic cycles, paths and trees

In this paper we consider the problem of partitioning complete multipartite graphs with edges colored by 2 colors into the minimum number of vertex disjoint monochromatic cycles, paths and trees, respectively. For general graphs we simply address the decision version of these three problems the 2-PGMC, 2-PGMP and 2-PGMT problems, respectively. We show that both 2-PGMC and 2-PGMP problems are NP-complete for complete multipartite graphs and the 2-PGMT problem is NP-complete for bipartite graphs. This also implies that all these three problems are NP-complete for general graphs, which solves a question proposed by the authors in a previous paper. Nevertheless, we show that the 2-PGMT problem can be solved in polynomial time for complete multipartite graphs. Research supported by NSFC.     

Benchmark Duration of Work Hours for Development of Fatigue Symptoms in Japanese Workers with Adjustment for Job‐Related Stress

The objective of this study was to calculate benchmark durations and lower 95% confidence limits for benchmark durations of working hours associated with subjective fatigue symptoms by applying the benchmark dose approach while adjusting for job‐related stress using multiple logistic regression analyses. A self‐administered questionnaire was completed by 3,069 male and 412 female daytime workers (age 18–67 years) in a Japanese steel company. The eight dependent variables in the Cumulative Fatigue Symptoms Index were decreased vitality, general fatigue, physical disorders, irritability, decreased willingness to work, anxiety, depressive feelings, and chronic tiredness. Independent variables were daily working hours, four subscales (job demand, job control, interpersonal relationship, and job suitability) of the Brief Job Stress Questionnaire, and other potential covariates. Using significant parameters for working hours and those for other covariates, the benchmark durations of working hours were calculated for the corresponding Index property. Benchmark response was set at 5% or 10%. Assuming a condition of worst job stress, the benchmark duration/lower 95% confidence limit for benchmark duration of working hours per day with a benchmark response of 5% or 10% were 10.0/9.4 or 11.7/10.7 (irritability) and 9.2/8.9 or 10.4/9.8 (chronic tiredness) in men and 8.9/8.4 or 9.8/8.9 (chronic tiredness) in women. The threshold amounts of working hours for fatigue symptoms under the worst job‐related stress were very close to the standard daily working hours in Japan. The results strongly suggest that special attention should be paid to employees whose working hours exceed threshold amounts based on individual levels of job‐related stress.