北方半干旱区氮肥不同配施方式对小南瓜产量的影响

小南瓜是北方半干旱区增加经济产值的适生作物之一。研究选用日本赤甘栗品种,采用田间小区试验,研究了在两种灌溉方式(灌溉、灌溉施肥)和四个牛粪氮添加水平(25、50、75、100 kg N/hm~2)处理下氮肥不同配施方式对小南瓜产量的影响。结果表明,在小南瓜生长前期,滴灌施肥方式可有效促进叶绿素的积累及叶片的复壮,有利于植株生长。单施有机肥组,随着牛粪氮添加水平的增加小南瓜产量未见明显增加,平均产量为10 t/hm~2;有机肥结合灌溉施肥组,随着牛粪氮添加水平的增加小南瓜产量显著增加,最高达到21.5 t/hm~2。当总氮添加量为100~140 kg/hm~2,有机无机肥配比为3:7~5:5时,小南瓜产量比单施牛粪肥增产60%,平均达到16 t/hm~2。     

Assessment of social implications of nanotechnologies in Japan: Application of problem structuring method based on interview surveys and cognitive maps

This paper aims at developing a problem structuring method based on interview surveys of key stakeholders and a well-known visualizing technique, called a “cognitive map.” We found that this new method, based on an interactive process with key stakeholders, was able to draw broader and more detailed issues than was previously anticipated. We also found that the proposed method was useful for the analysis of the societal implications of emerging technologies, such as nanotechnologies, which are not easily defined. It is confirmed that the proposed method can clarify common and diversified issues based on the perception of key stakeholders and identify additional stakeholders to be interviewed.     

Prediction in the lognormal regression model with spatial error dependence

In the context of the lognormal regression model with spatial error dependence, the present study examines correction of a bias in prediction. If interest lies in the predicted mean value of the dependent variable, antilogarithmic transformation of the predicted mean value of the regressand produces a bias. In order to correct such a transformation bias, we derive several alternative predictors by extending some of the predictors suggested for the lognormal regression model with spherical disturbances. Behaviors of our predictors are described in a theoretical manner, and their performances are assessed in an experimental manner. Extension of an asymptotically unbiased predictor is shown to be useful.     

Productivity, returns to scale and product differentiation in the retail trade industry: an empirical analysis using Japanese firm-level data

This paper examines productivity and returns to scale under the assumption of monopolistic competition using Japanese firm-level data. Although differentiating products (services) is considered important in firms?? strategies and productivity growth, it has not been sufficiently investigated in previous studies. In this paper, we study this issue in two retail trade industries, department stores and supermarkets, applying the model of Melitz (2000). Our results indicate that the standard production function is not relevant to estimate productivity in imperfectly competitive markets. It also suggests that the market structure should be carefully considered in productivity analysis. In addition, product differentiation has a positive effect on firms?? revenue for the supermarkets. Furthermore, the retail trade industries possibly follow increasing returns to scale. Thus, policy measures that promote economies of scale and product differentiation should contribute to further growth in these industries. In addition, the results indicate that the regulatory reform of the retail trade industry in 2000 increased the gap between winners and losers in terms of productivity.     

Asymptotics for panel quantile regression models with individual effects

This paper studies panel quantile regression models with individual fixed effects. We formally establish sufficient conditions for consistency and asymptotic normality of the quantile regression estimator when the number of individuals, n$n$, and the number of time periods, T$T$, jointly go to infinity. The estimator is shown to be consistent under similar conditions to those found in the nonlinear panel data literature. Nevertheless, due to the non-smoothness of the objective function, we had to impose a more restrictive condition on T$T$ to prove asymptotic normality than that usually found in the literature. The finite sample performance of the estimator is evaluated by Monte Carlo simulations.     

Implementation of HACCP in the risk management of medical waste generated from endoscopy

Medical waste poses health hazards, increases the environmental load and is costly to dispose of. To solve the above problems, we applied the hazard analysis and critical control point system (HACCP) to the management of wastes generated from endoscopy. First, the wastes in three hospitals were quantified. The number and weight of waste per case differed significantly among the three hospitals. Second, HACCP was applied to the endoscopy unit of Hospital X for a year. Wastes were segregated into five types and weighed. We found that 25.8% of ‘infectious waste’ was in fact ‘non‐infectious waste’ and ‘non‐infectious plastic waste’. The numbers of needles and needle caps did not correspond in two occasions (needle‐loss rate: 0.42%). Bacterial counts of the waste container were determined to investigate infection hazard. The counts were 0 cfu/cm² in all examinations except one occasion. The waste control manifests were reviewed, and all entries were consistent with the waste sent for disposal. In Hospital X where implementation of HACCP was attempted, reduction of environmental load and cutting of disposal cost are anticipated by changing the categories of waste segregation. The results suggest that hospital wastes should be managed more safely by HACCP.     

Optimal degree of privatization and the environmental problem

We determine the optimal degree of privatization in a mixed duopoly when the environmental problem exists. With regard to the ownership of the private firms, we analyze two cases: (h) the private firm is owned by domestic private investors and (f) it is owned by foreign private investors. A comparison of the two cases presents the following results. Partial privatization is always desirable in (h), and the optimal degree of privatization is independent of the degree of environmental damage. However, in (f), whether partial privatization is desirable or not depends on the degree of environmental damage: there are cases where full privatization or full nationalization is optimal.     

Important attributes of lodgings to gain repeat business: A comparison between individual travels and group travels

The purpose of this study is to investigate the attributes of the satisfaction that are related to the lodging-guests’ tendency to revisit the lodgings and to compare these attributes among the different travel styles, such as individual travel, travel with friends or as a couple, and travel with family. We examine 6351 guest evaluations from a highly popular travel reservations website. Multinomial logistic regression analyses are performed and they show that the important attributes for lodgings to gain repeat business vary among their guest's travel styles.     

The “flying geese” model of Asian economic development: origin, theoretical extensions, and regional policy implications

This paper presents a comprehensive review of the “flying geese” (FG) model, which recently has become well known as a way of explaining rapid economic growth in East Asia. Kaname Akamatsu’s 1930s work introduced the concept. Through statistical analysis of industrial development in pre-war Japan, this author followed Akamatsu in developing a theoretical model called Kojima Model I. Subsequent works produced Kojima Models II and III.The regional transmission of FG industrialization has been noted as an engine of Asian economic growth, due in part to Saburo Okita’s forceful presentation of the theme of the FG model in a 1985 lecture. It is hoped that this paper will help to advance a better understanding of the FG model, its historical origin, its theoretical extensions, and its relevancy, as well as its incompleteness as a model of economic development.