A note on generalized wald’s method

Let {v _n(θ)} be a sequence of statistics such that whenθ =θ ₀,v _n(θ ₀) N _p(0,Σ), whereΣ is of rankp andθ εR ^d. Suppose that underθ =θ ₀, {Σ _n} is a sequence of consistent estimators ofΣ. Wald (1943) shows thatv _n ^T (θ ₀)Σ _n ⁻¹ v _n(θ ₀) x ²(p). It often happens thatv _n(θ ₀) N _p(0,Σ) holds butΣ is singular. Moore (1977) states that under certain assumptionsv _n ^T (θ ₀)Σ _n ⁻ v _n(θ ₀) x ²(k), wherek = rank (Σ) andΣ _n ⁻ is a generalized inverse ofΣ _n. However, Moore’s result as stated is incorrect. It needs the additional assumption that rank (Σ _n) =k forn sufficiently large. In this article, we show that Moore’s result (as corrected) holds under somewhat different, but easier to verify, assumptions. Research partly supported by the U.S. Army Research Office through the Mathematical Sciences Institute at Cornell University.     

The concept study of Servqual method’s gap

The methodology of conduct, presented in this publication, allows conducting the study of clients’ satisfaction of services in a complex manner and at the same time, it allows getting to know all problems appearing in the process of their provision. Gap no 5 expresses a general client’s perception of services and allow defining his satisfaction. Gap 4 allows defining in what range the organization provides clients with false and distorted information in its promotion and advertising materials, which in consequence influence on their satisfaction. The result from gap no 4 can be used when planning promotion campaign. Gap no 2 and 3 allow defining if the organization is realizing the planned strategy of quality. It allows defining which employees provide services of a low quality and then by means of the application the appropriate motivation tools it allow to cut it out. Finally, gap no 1 which allow defining problems connected with marketing communication. It allows finding client’s needs which organization does not know and which should be included in its strategy.     

A survey of poverty research in Russia: Does it follow the scientific method?

This paper presents the first critical review of the literature on poverty published in Russia between 1992 and 2006. Using a dataset of about 250 publications in Russian scientific journals we assess whether the poverty research in Russia satisfies the general criteria of a scientific publication and if such studies could provide reliable guidance to the Russian government as it maps out its anti-poverty policies. Our findings indicate that only a small proportion of papers on poverty published in Russia in 1992–2006 follow the universally recognized principles of the scientific method. The utility of policy advice based on such research is questionable. We also suggest certain steps that could, in our view, improve the quality of poverty research in Russia.     

An application of Stein’s method to limit theorems for pairwise negative quadrant dependent random variables

Stein’s method is used to derive an error in normal approximation for sums of pairwise negative quadrant dependent random variables, but under the assumption of second moment only. This allows us to derive a central limit theorem for pairwise negative quadrant dependent random variables with Lindeberg’s condition. Research supported by Science Foundation of Zhejiang Provincial Education(no. 20060122)     

Diversification strategy,CEO management style and firm performance: an application of Heckman’s two-stage method

This paper aims to explore whether CEOs’ management style as agents or as stewards, which depends on their psychological and situational characteristics, moderates the effect of the diversification strategy on firm performance. After applying Heckman’s two-stage method to control econometrically for endogeneity bias in empirical work, results demonstrate that the relationship between diversification and profitability varies significantly depending on the management style of the diversifying CEO.     

Incentive regulation and performance measurement of Taiwan’s incineration plants: an application of the four-stage DEA method

The aim of this paper is to provide a technical efficiency assessment of Taiwan’s incineration plants as the basis of incentive regulation schemes. We integrate the four-stage approach with Simar and Wilson’s (in J Econom 136:31–64, 2007) double bootstrapping to filter out the impacts of external variables in the efficiency measurement. Empirical results show that there is room for 15 % cost reductions and capacity, ownership, location and experience are all influential in improving the performance of these plants. We also demonstrate how the results can be applied to modify a yardstick incentive scheme.     

Forecasting sales using online review and search engine data: A method based on PCA–DSFOA–BPNN

Traditional sales forecasting methods are mainly based on historical sales data, which result in a certain lag. The relationship between sales volume and its influencing factors is intricate and often non-linear. In view of this, we propose a novel product forecasting method using online reviews and search engine data. Firstly, a dictionary-based sentiment analysis method is developed to convert the textual review concerning each attribute of the product into the corresponding sentiment score. And by combining the prospect theory and relevant online review data, sentiment indices in each period are calculated. Subsequently, data of product-related Baidu search words with different lag orders are collected and screened by time difference correlation analysis. Finally, the forecast model, PCA–DSFOA–BPNN, is constructed by combining the principal component analysis (PCA), the back propagation neural network (BPNN), and the improved fruit fly optimization algorithm (DSFOA), in which sentiment indices, Baidu search data, and historical sales volume are input data. Taking the monthly sales forecast of 14 automobile models as a case study, we observe that the proposed forecast method can effectively improve the forecast accuracy with good robustness.     

Elfving’s method for <Emphasis Type="Italic">m</Emphasis>-dimensional models

Elfvings method is a well known graphical procedure for obtaining c-optimal designs. Although the method is valid for any dimension it is rarely used for more than two parameters. Its usefulness seems to be constrained by the difficulty on the construction of the Elfving set. In this paper a computational procedure for finding c-optimal designs using Elfvings method for more than two dimensions is provided. It is suitable for any model, achieving an efficient performance for three or four dimensional models. The procedure can be implemented in most programming languages.Acknowledgments. The authors would like to thank Dr. Torsney for his helpful comments. This research was supported by a grant from JCyL SA004/01.     

Overcoming the ethnocentric firm? – foreign fresh university graduate employment in Japan as a new international human resource development method

Abstract

This article analyses a new and, by international comparison, distinct recruitment trend – the systematic hiring of foreign fresh university graduates (FFGs) into Japanese multinational enterprises’ (MNEs) operations in Japan. Our explorative research, which is based on interviews with HR managers and FFGs, offers three major findings related to international HR development methods. Firstly, the inpatriate literature has identified the roles of foreign (subsidiary) staff as knowledge conduits and boundary-spanners between headquarters and subsidiaries. While such objectives do not drive Japan’s FFG hiring trend, we find similar challenges in terms of the absorptive capacities of headquarters. Secondly, following a Varieties-of-Capitalism perspective, we argue that FFG hiring is an institutional answer to the particularities of Japan’s employment system. Aiming at internationalizing headquarters from within, it contributes to resolving the internationalization conundrum of Japanese MNEs, but rather than overcoming the existing ethnocentric HR model it accommodates this orientation. Thirdly, we advance the general HR literature by proposing a new framework that addresses the viability of international personnel development methods in dependence of the workforce diversity and distinctiveness of employment practices in headquarters. We locate FFG hiring, inpatriation and self-initiated assignments within this framework.     

Evaluation of the convergence between “self-reporters” and “proxies” in a disability questionnaire by means of behaviour coding method

Household surveys often require including proxy reporters to obtain information about other household members who cannot be interviewed. The participation of proxies can undermine survey data quality due to the fact that proxies must respond to questions thinking about other people. The objectives of the present study were to analyze the behaviour of proxy reporters and evaluate the convergence between the answers given by proxies and self-reporters by means of behaviour coding. This improves the evaluation of convergence, since only adequate (i.e., interpretable) answers given by both types of informant are taken into account. Responses to a disability questionnaire employed by an official statistical institute were analyzed. The questionnaire includes 11 questions about different limitations related to everyday activities. 16 self-reporter and 16 proxies formed 16 couples whose members lived together and supported a direct family relation. The results show a high percentage (52%) of convergence between both types of informant, although fluctuating across the questions and the couples. Proxies showed relatively more adequate behaviour during the interaction than self-reporters. From this we conclude that proxies can be considered at least as good informants as self-reporters from an interviewer-respondent interaction perspective. Future research should address the impact of proxy responses on survey validity.     

How does the development of urban agglomeration affect the electricity efficiency of resource-based cities?—An empirical research based on the fsQCA method

Urban agglomeration impacts the electricity efficiency of resource-based cities. Under the background, the paths that lead to high level electricity efficiency are not clear. Therefore, it is difficult to guide the socio-economic planning. This paper assumes that the influence of urban agglomeration includes agglomeration and diffusion effect. Then, this paper uses fuzzy-set qualitative comparative analysis (fsQCA) to explore the paths lead to high-level electricity efficiency. The process includes the measurement of electricity efficiency, the selection and quantification of action conditions, and path analysis. Four main conclusions are obtained. First, the positive impact of urban agglomeration on the electricity efficiency of resource-based cities is achieved through the optimal allocation of regional resources. Second, compared with the paths under diffusion effect, the paths under agglomeration effect are more diversified. Third, the effects of two kinds of paths are obvious: the agglomeration of non-resource-based industries to central cities and the diffusion of green production from central cities. Fourth, the diffusion of green production depends on the sustainability of resource-based cities. The research conclusion can improve the energy and sustainability policies of urban agglomerations and resource-based cities, and the improved policies will improve the efficiency of regional resource allocation and will promote the electricity efficiency and sustainability of resource-based cities.     

Using <Emphasis Type="Italic">K</Emphasis>-means method and spectral clustering technique in an outfitter’s value analysis

This study applies K-means method and spectral clustering technique in the customer data analysis of an outfitter in Taipei City, Taiwan. The data set contains transaction records of 551 customers from April 2004 to March 2006. The differences between the two clustering techniques mentioned here are significant. K-means method is more capable of dealing with linear separable input, while spectral clustering technique might have the advantage in non-linear separable input. Thus, it would be of interest to know which clustering technique performs better in a real-world case of evaluating customer value when the type of input space is unknown. By using cluster quality assessment, this study found that spectral clustering technique performs better than K-means method. To summarize the analysis, this study also suggests marketing strategies for each cluster based on the results generated by spectral clustering technique.