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281.
282.
T. J. Rao 《Metrika》1972,18(1):209-215
Summary In an earlier paper [Rao 1966] an exact expression for the variance of the ratio estimator under theMidzuno-Sen sampling scheme is obtained and here we study some of the interesting properties of the coefficients involved in this expression which depend on the auxiliary information. Use of these coefficients is made of in finding out an exact expression for the Bias and Mean Square Error of the ratio estimator under Simple Random Sampling With-Out Replacement (SRSWOR) scheme.  相似文献   
283.
This article focuses on the structuring of the corporate headquarters in a franchise organization. Four essential issues that are related to franchisors organizational structure are discussed—homogeneity and heterogeneity of franchisors structure, company-owned and franchise arrangement, the dynamics between strategy and structure, and performing innovative and administrative functions simultaneously in the headquarters. Propositions are given for each issue. The results of qualitative analysis associated with each issue are discussed.  相似文献   
284.
The purpose of this paper is to provide evidence that the debate between quantitative and qualitative is divisive and, hence, counterproductive for advancing the social and behavioral science field. We advocate that all graduate students learn to utilize and to appreciate both quantitative and qualitative research methodologies. As such, students will develop into pragmatist researchers who are able to utilize both quantitative and qualitative techniques when conducting research. We contend that the best way to accomplish this is by eliminating quantitative research methodology and qualitative research methodology courses from curricula and replacing these with research methodology courses at different levels that simultaneously teach both quantitative and qualitative techniques within a mixed methodological framework.An earlier version of this article received the 2003 Southwest Educational Research Association (SERA) Outstanding Paper Award.  相似文献   
285.
Robustness issues in multilevel regression analysis   总被引:8,自引:0,他引:8  
A multilevel problem concerns a population with a hierarchical structure. A sample from such a population can be described as a multistage sample. First, a sample of higher level units is drawn (e.g. schools or organizations), and next a sample of the sub‐units from the available units (e.g. pupils in schools or employees in organizations). In such samples, the individual observations are in general not completely independent. Multilevel analysis software accounts for this dependence and in recent years these programs have been widely accepted. Two problems that occur in the practice of multilevel modeling will be discussed. The first problem is the choice of the sample sizes at the different levels. What are sufficient sample sizes for accurate estimation? The second problem is the normality assumption of the level‐2 error distribution. When one wants to conduct tests of significance, the errors need to be normally distributed. What happens when this is not the case? In this paper, simulation studies are used to answer both questions. With respect to the first question, the results show that a small sample size at level two (meaning a sample of 50 or less) leads to biased estimates of the second‐level standard errors. The answer to the second question is that only the standard errors for the random effects at the second level are highly inaccurate if the distributional assumptions concerning the level‐2 errors are not fulfilled. Robust standard errors turn out to be more reliable than the asymptotic standard errors based on maximum likelihood.  相似文献   
286.
Business school deans’ feelings about the importance of various teaching research and service activities in the roles played by holders of endowed chairs in Entrepreneurship were contrasted with the views of chair holders themselves, based on their experiences. Differences were highlighted and discussed. Results suggest that the chair holder role is negotiated between multiple constituencies, with deans’ influence being strong but limited. Implications for individuals aspiring to hold chairs are discussed.  相似文献   
287.
This paper utilizes the average derivative estimation of Stoker (1986) and the pesudo-likelihood estimation of Fan, Li, and Weersink (1996) to estimate a semiparametric stochastic frontier regression, y = g(x) + , where the function g(.)is unknown and is a composite error in a standard setting. The proposed semiparametric method of estimation is applied to data on farmers' credit unions in Taiwan. Empirical results show that the banking services of the farmers' credit unions is subject to economies of scale, but high degree of cost inefficiency in operation.  相似文献   
288.
The present study empirically examines the contribution of the acquired banks in only the nonconglomerate types of mergers (i.e., banks with banks), where the bulk of the payment is in the form of equity to the acquiring bank and finds overwhelmingly statistically significant evidence that nonconglomerate types of mergers definitely reduce the total as well as the unsystematic risk while having no statistically significant effect on systematic risk. Therefore, it seems that diversification may be a possible motive for bank mergers.  相似文献   
289.
Airports in the US air transport network have become increasingly congested, leading to delays for business travelers and freight shipments. Since disruptions in one part of the network exacerbate problems throughout the system, airport infrastructure expansions to enhance air traffic flows confer travel-time savings and reliability benefits, and thus increased worker productivity and shipping efficiency for manufacturing firms. We evaluate such spillovers, and find that higher own-state airport infrastructure implies lower manufacturing costs from both labor- and materials-savings. Airport expansion in connected states has a comparable effect for states with hub airports, and an even greater impact for other states.  相似文献   
290.
We present a probabilistic model based on the one developed by Hernández Mendo and Anguera (Revista de Psicologíca Social, 16(1), 71–93, 2001). Here we have tried to break down the interaction contexts that the opposing teams are able to generate and transform during the game. We are aware that a given player or team does not produce consistent behaviour in similar situations. However, a degree of uncertainty is assumed to exist regarding whether the results obtained are a specific function of the analysis used. In order to carry out this research a category system which optimized that used in the previous model was developed. This system should enable the interaction between teams to be observed within the actual play of a soccer game. A lag sequential analysis was performed on the basis of a coding of the behavioural flow. After describing the behavioural patterns obtained a probabilistic model of the development of play in soccer is proposed.  相似文献   
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