Monotone-path Dutta-Ray solutions on convex games

It is well known that on the domain of convex games, the Dutta-Ray solution satisfies many desirable properties such as population-monotonicity, max consistency, converse max consistency, and conditional self-consistency. In this paper, we define a family of possibly non-symmetric and non-homogeneous generalizations of the Dutta-Ray solution, which we refer to as “monotone-path Dutta-Ray solutions.” We show that above four properties are preserved by our generalizations. Received: 25 August 2000/Accepted: 11 September 2001     

A Test for Instrument Validity

This paper develops a specification test for instrument validity in the heterogeneous treatment effect model with a binary treatment and a discrete instrument. The strongest testable implication for instrument validity is given by the condition for nonnegativity of point‐identifiable compliers' outcome densities. Our specification test infers this testable implication using a variance‐weighted Kolmogorov–Smirnov test statistic. The test can be applied to both discrete and continuous outcome cases, and an extension of the test to settings with conditioning covariates is provided.     

Study on workloads of human care worker with the introduction of IT system - the characteristics of work loads by observational research and the suggestions for KAIZEN

The purpose of this study was to clarify the characteristic of workloads on human care worker with the introduction of IT system, and suggested the support measures for KAIZEN in Japan. The investigation method is workflow line and hearing with a focus on work observation. The objects were 8 human care workers of the acute hospital that introduced an electronic system. By the introduction of the electronic chart, the nurse station sojourn time decreased, sickroom sojourn time increased, and time about direct nursing care to a patient increased. In addition, access to patient information became easy, and the offer of the health care service based on correct information came to be possible in real time. By The point of workflow line, it was effect that moving lengths decreased in order to install the electronic chart in patients' rooms. Though, it was a problem that it hasn't formed where to place the instruments such as sphygmomanometer, clinical thermometer and others.     

Development of the workflow kine systems for support on KAIZEN

In this paper, we introduce the new workflow line system consisted of the location and image recording, which led to the acquisition of workflow information and the analysis display. From the results of workflow line investigation, we considered the anticipated effects and the problems on KAIZEN. Workflow line information included the location information and action contents information. These technologies suggest the viewpoints to help improvement, for example, exclusion of useless movement, the redesign of layout and the review of work procedure. Manufacturing factory, it was clear that there was much movement from the standard operation place and accumulation residence time. The following was shown as a result of this investigation, to be concrete, the efficient layout was suggested by this system. In the case of the hospital, similarly, it is pointed out that the workflow has the problem of layout and setup operations based on the effective movement pattern of the experts. This system could adapt to routine work, including as well as non-routine work. By the development of this system which can fit and adapt to industrial diversification, more effective "visual management" (visualization of work) is expected in the future.     

Development of a Dose‐Response Model for SARS Coronavirus

In order to develop a dose‐response model for SARS coronavirus (SARS‐CoV), the pooled data sets for infection of transgenic mice susceptible to SARS‐CoV and infection of mice with murine hepatitis virus strain 1, which may be a clinically relevant model of SARS, were fit to beta‐Poisson and exponential models with the maximum likelihood method. The exponential model (k= 4.1 × l0²) could describe the dose‐response relationship of the pooled data sets. The beta‐Poisson model did not provide a statistically significant improvement in fit. With the exponential model, the infectivity of SARS‐CoV was calculated and compared with those of other coronaviruses. The does of SARS‐CoV corresponding to 10% and 50% responses (illness) were estimated at 43 and 280 PFU, respectively. Its estimated infectivity was comparable to that of HCoV‐229E, known as an agent of human common cold, and also similar to those of some animal coronaviruses belonging to the same genetic group. Moreover, the exponential model was applied to the analysis of the epidemiological data of SARS outbreak that occurred at an apartment complex in Hong Kong in 2003. The estimated dose of SARS‐CoV for apartment residents during the outbreak, which was back‐calculated from the reported number of cases, ranged from 16 to 160 PFU/person, depending on the floor. The exponential model developed here is the sole dose‐response model for SARS‐CoV at the present and would enable us to understand the possibility for reemergence of SARS.     

Income earning opportunity and work performance affect donating behavior: Evidence from dictator game experiments

Using dictator game experiments, the authors investigate the effect on donation of the dictator and/or recipient working prior to the dictator donating. We focus on two issues that previous studies have not considered. First, we examine the impact on donating behavior of a difference in endowment caused by the dictator's work performance. Second, we explore donation behavior when the recipient's work does not yield income or affect the dictator's endowment, but the recipient's work performance is made known to the dictator. Experimental results indicate that donating behavior is affected not only by the dictator working, but also by the recipient working. In addition, donating behavior is affected by income level, as determined by the dictator's work performance, and is influenced by the recipient's work performance, two findings not previously reported.     

GPS cell phone tracking in the Greater Tokyo Area: A field test on raccoon dogs

We tested instantaneous GPS cell phone telemetry to record movement data of raccoon dogs (Nyctereutes procyonoides) in Abiko city, Greater Tokyo, Japan. We monitored the changes in locations of six raccoon dogs in various land use types such as roads, golf courses, towns, rice and crop paddies, and forest. Data were downloaded instantaneously using cell phone networks and the internet, remotely to a desktop computer. We obtained 410 location points and the maximum duration of individual tracking was 144 hours. The success rate of GPS positioning varied among individuals. On average, the success rate of three raccoon dogs in a relatively open area was 98% and that of three raccoon dogs in a mosaic area was 70%. In total, 372 of the data points (91 % of all downloaded data) with reliable accuracy were used to analyze movement speed during the day time as well as habitat use of the raccoon dogs, revealing various spatial and temporal behavioral patterns. Human activities were the likely cause of characteristic behaviors in tall weed patches and golf courses, and daily patterns of movement. Our results indicate the potential utility of GPS cell phone tracking to efficiently monitor and manage wildlife in changing urban environments.     

The Performance Implications of Ownership-driven Governance Reform

This paper explores the performance impact of recent changes in foreign shareholdings and boardroom reforms in Japan. Empirical research on the impact of reform on the Japanese corporate governance system could provide useful lessons for their European counterparts who are themselves facing similar pressures to reform. We found that although participation of outside directors in strategic decision-making was associated with positive stock returns, the increase in the ratio of outside directors, the separation of the board members and executive officers, and the reduction of board size were not related to firm performance.     

Dose-response assessment for influenza A virus based on data sets of infection with its live attenuated reassortants

Reported data sets on infection of volunteers challenged with wild-type influenza A virus at graded doses are few. Alternatively, we aimed at developing a dose-response assessment for this virus based on the data sets for its live attenuated reassortants. Eleven data sets for live attenuated reassortants that were fit to beta-Poisson and exponential dose-response models. Dose-response relationships for those reassortants were characterized by pooling analysis of the data sets with respect to virus subtype (H1N1 or H3N2), attenuation method (cold-adapted or avian-human gene reassortment), and human age (adults or children). Furthermore, by comparing the above data sets to a limited number of reported data sets for wild-type virus, we quantified the degree of attenuation of wild-type virus with gene reassortment and estimated its infectivity. As a result, dose-response relationships of all reassortants were best described by a beta-Poisson model. Virus subtype and human age were significant factors determining the dose-response relationship, whereas attenuation method affected only the relationship of H1N1 virus infection to adults. The data sets for H3N2 wild-type virus could be pooled with those for its reassortants on the assumption that the gene reassortment attenuates wild-type virus by at least 63 times and most likely 1,070 times. Considering this most likely degree of attenuation, 10% infectious dose of H3N2 wild-type virus for adults was estimated at 18 TCID50 (95% CI = 8.8-35 TCID50). The infectivity of wild-type H1N1 virus remains unknown as the data set pooling was unsuccessful.