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1.
2.
For the problem of adjudicating conflicting claims, a rule is consistent if the choice it makes for each problem is always in agreement with the choice it makes for each “reduced problem” obtained by imagining that some claimants leave with their awards and reassessing the situation from the viewpoint of the remaining claimants. We develop a general technique to determine whether a given two-claimant rule admits a consistent extension to general populations, and to identify this extension if it exists. We apply the technique to a succession of examples. I gratefully acknowledge support from NSF under grant SBR-9731431 and SES 0214691, and the comments of Carmen Bevia, Rodrigo Velez, Chun-Hsien Yeh, and a referee.  相似文献   

3.
We consider a problem of selecting the best treatment in a general linear model. We look at the properties of the natural selection rule. It is shown that the natural selection rule is minimax under to “0–1” loss function and it is a Bayes rule under a monotone permutation invariant loss function with respect to a permutation invariant prior for every variance balanced design. Some other condition on the design matrix is given so that a Bayes rule with respect to a normal prior will be of simple structure.  相似文献   

4.
We calculate the proportion of preference profiles where “small” coalitions of agents may successfully manipulate any given scoring rule and show that it decreases to zero at a rate proportional to with the number of agents. If agents have to incur a small cost in order to decide how to manipulate the voting rule, our results imply that scoring rules are robust to such manipulation in large groups of agents. We present examples of asymptotically strategyproof and non strategyproof Condorcet consistent rules. We thank Eric Maskin and Shmuel Nitzan for useful discussions. We also thank seminar participants at Harvard, Haifa, and Technion universities for their comments. Neeman is grateful for the generous financial support of the NSF under grant SBR-9806832.  相似文献   

5.
Tests for the goodness-of-fit problem based on sample spacings, i.e., observed distances between successive order statistics, have been used in the literature. We propose a new test based on the number of “small” and “large” spacings. The asymptotic theory under close alternative sequences is also given thus enabling one to calculate the asymptotic relative efficiencies of such tests. A comparison of the new test and other spacings tests is given.  相似文献   

6.
Contemporary society is experiencing dramatic shifts in its expectations for business and its practices. Within the academic realm two voices of change are the “feminist” and “business ethics” perspectives; unfortunately, these two perspectives often advocate conflicting expectations for business organizations. The purpose of this article is to provide an analysis of the expectations each perspective advocates, and to draw relevant implications for future business practices. Our general conclusion is that the feminist perspective maintains a system of gender dichotomies and fails to recognize shifts in the balance of powers. In contrast, a business ethics perspective moves beyond gender issues and dichotomous systems to the recognition that contemporary society is comprised of minorities, and that the rights of all minorities must be recognized and balanced. We suggest that the feminist perspective must reposition with the rapid shifts currently occurring within our society before it can be a “voice” that should be listened to by business organizations.  相似文献   

7.
M. Riedle  J. Steinebach 《Metrika》2001,54(2):139-157
We study a “direct test” of Chu and White (1992) proposed for detecting changes in the trend of a linear regression model. The power of this test strongly depends on a suitable estimation of the variance of the error variables involved. We discuss various types of variance estimators and derive their asymptotic properties under the null-hypothesis of “no change” as well as under the alternative of “a change in linear trend”. A small simulation study illustrates the estimators' finite sample behaviour.  相似文献   

8.
The main purpose of the article is to educate managers about potential difficulties caused by breach of fiduciary duties on the part of agents/employees within their organization. Managers will learn how to recognize common problem situations so they can take steps to avoid, or at least mitigate, any resulting damage. This article highlights 12 frequent situations—the “dirty dozen”—that pose dangers for business organizations.  相似文献   

9.
While often well-meant and sometimes unintended, nagging is an irritation we can easily do without. Whether personal or electronic, low-tech or high, it matters not. With PC proliferation, problem potential increases—even at home. Resisting the urge to telecommute unless anticipated gains can be “proved” in advance, and self-discipline if and when the PC becomes a “family member,” are urged.  相似文献   

10.
The “winner-winner, winner-loser, gone” methodology allows tests for short-term performance persistence for government and corporate fixed income mutual funds from 1990 to 1999. Persistence occurs when “winner” (loser) funds remain “winner” (loser) funds. If intermediate-term (long-term) bond returns are higher than long-term (intermediate-term) bond returns for successive years, the z-statistic is positive. Persistence is negative in the opposite case, and the pattern holds for longer lag periods. Statistical significance and consistency between the sign of persistence and bond returns indicates persistent returns on bond funds, but the nature of persistence is driven by changes in interest rates. The authors would like to acknowledge the research assistance of Michael Serra and Michael Wieczorek. This research was supported in part by the McDonough School of Business and the Capital Markets Research Center at Georgetown University.  相似文献   

11.
This paper covers some of the past accomplishments of DEA (Data Envelopment Analysis) and some of its future prospects. It starts with the “engineering-science” definitions of efficiency and uses the duality theory of linear programming to show how, in DEA, they can be related to the Pareto–Koopmans definitions used in “welfare economics” as well as in the economic theory of production. Some of the models that have now been developed for implementing these concepts are then described and properties of these models and the associated measures of efficiency are examined for weaknesses and strengths along with measures of distance that may be used to determine their optimal values. Relations between the models are also demonstrated en route to delineating paths for future developments. These include extensions to different objectives such as “satisfactory” versus “full” (or “strong”) efficiency. They also include extensions from “efficiency” to “effectiveness” evaluations of performances as well as extensions to evaluate social-economic performances of countries and other entities where “inputs” and “outputs” give way to other categories in which increases and decreases are located in the numerator or denominator of the ratio (=engineering-science) definition of efficiency in a manner analogous to the way output (in the numerator) and input (in the denominator) are usually positioned in the fractional programming form of DEA. Beginnings in each of these extensions are noted and the role of applications in bringing further possibilities to the fore is highlighted.
J. ZhuEmail:
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12.
The Blocking Lemma identifies a particular blocking pair for each non-stable and individually rational matching that is preferred by some agents of one side of the market to their optimal stable matching. Its interest lies in the fact that it has been an instrumental result to prove key results on matching. For instance, the fact that in the college admissions problem the workers-optimal stable mechanism is group strategy-proof for the workers and the strong stability theorem in the marriage model follow directly from the Blocking Lemma. However, it is known that the Blocking Lemma and its consequences do not hold in the general many-to-one matching model in which firms have substitutable preference relations. We show that the Blocking Lemma holds for the many-to-one matching model in which firms’ preference relations are, in addition to substitutable, quota q-separable. We also show that the Blocking Lemma holds on a subset of substitutable preference profiles if and only if the workers-optimal stable mechanism is group strategy-proof for the workers on this subset of profiles.  相似文献   

13.
Alcuni Autori ritengono che non abbia senso il costo del denaro, in uno schema lineare in cui si può ripartire il proprio denaro in tutte e sole le operazioni che determinano il tasso di sconto. La conclusione di tali Autori appare azzardata: infatti il loro risultato discende da una ipotesi estranea al modello lineare. In questo lavoro io interpreto lo stesso modello, mostro che in esso ha senso il costo del denaro e propongo delle impostazioni alternative.
An interesting economic problem consist in the search of the optimal allocation of one’s monetary resources in different financial transactions. We often consider as “optimal” the allocation which makes the sum of the actual values of investiments the highest possible, within the limits of all feasible operations. These values are reckoned according to the discount rates established by the financial market. This type of abstraction can be acceptable when we can split our capital into a number of operations that are on the whole negligible, if compared with the movement of the market. In case of a considerable turn over that may therefore affect the cost of money, it follows that we can’t determine an appropriate discount rate before establishing the distribution policy; on the other hand we cannot determine the distribution policy before defining the discount rate. As a border-line case we have that of an “enclosed” economy, where funds can be rationed into all and only those operations which determine the cost of capital. That is the case of “pure capital rationing”. To solve the problem of reckoning the cost of capital under pure capital rationing, some Authors have formulated the two dual linear programs (1) and (2) and have deduced that f is the vector of market prices if and only if the optimal dual solution is equal to f. As that happens if and only if f=0, Burton and Damon [2] consider their “main result a rigorous proof that there does not exist a meaningful solution for the pure capital rationing problem” and conclude “that if there exist a solution to the problem it is not to be found by the traditional linear programming formulations”. On the contrary I demonstrate that f=0 is the only possible capital cost because of the hypotesis =f, which is not related to the linear pattern and is not acceptable from an economic-financial point of view. Then I demonstrate that the market prices are all and only those based on which the actual values of the operations considered are 0. Nor was it right to expect more sophisticated conclusions of such an elementary scheme. Finally I express an alternative linear formulation, where the dual optimal solutions are exactly the market prices.


Lavoro effettuato nell’ambito del G.N.A.F.A. del C.N.R.  相似文献   

14.
Metin  Nurcan 《Quality and Quantity》2012,46(4):1297-1309
The article examines whether the US threat perceptions defined in terms of federal government national defense outlays in billions of constant (FY 2000) dollars change along with periodical changes in international politics between 1945 and 2007. Three different models affecting direction of the US defense expenditures are developed. The first model are estimated by using five link functions even though results of only two of them, complementary log–log and cauchit, are presented. As complementary log–log produced the best results, others models are predicted by using only this function. The parameter estimates of complementary log–log function for the first model indicate that four of these variables (Ford, Carter, Reagan and Bush Sr.) out of eleven are significant in the category of presidents. “Truman Docrtrine/Cominform”, “Korean War”, “Vietnam War”, and “Invasion of Iraq” also seem to be the important independent variables on empirical grounds for the first model. While “Party”, “Invasion of Iraq”, “Vietnam War”, “Korean War”, and “Cuban Missile Crisis” constitute the important independent variables on empirical grounds for the second model, “Korean War”, “Vietnam War”, “Invasion of Iraq”, “Truman Docrtrine/Cominform”, “The Cold War and New World Order”, and “Cuban Missile Crisis” are important independent variables on empirical grounds for the third model. Estimations based on these three models therefore suggest that aforementioned independent variables do indeed have effect on the US defense expenditures.  相似文献   

15.
The purpose of this study is to explore the correlation between adolescent participation in leisure activity, its benefits, and coping with stress. Questionnaire surveys and structural equation model (SEM) were used for testing, and the analytical results showed that the model has good fit. The main findings of this study are: (1) youth participation in leisure activity would positively influence benefits of leisure activity; (2) participation in leisure activity has a significant positive correlation to adolescent coping with stress; (3) benefits of leisure activity has a significant positive influence on coping with stress. Research results showed that among participation in leisure activity, “kinetic activity” is the most important element for adolescent choice; among benefits of leisure activity, “enrich the quality of life” and “enhance self-worth” are most emphasized by adolescents. In terms of coping with stress, adolescents generally use “avoidance coping.” According to the research results, it is suggested that under the current social and cultural framework, promotion of adolescent participation in leisure activity can help them increase avoidance coping when faced with stress.  相似文献   

16.
Building upon a formerly performed study on port competitiveness, this article discusses the use of a stochastic frontier model as an interesting novel use to test, identify and correct respondents’ bias by applying it to competitiveness analysis based on perceptions of senior executives. Measuring the importance of competition determinants of seaports, conventionally analyzed using a SWOT-analysis based on (transport) infrastructure as a prime requirement for port activity growth, is an important issue to port management. However, it seems that the “institutional” environment of a seaport is also critical in obtaining a competitive advantage. In Haezendonck et al. (2000 and 2001) those port specific advantages and disadvantages were identified using factor analysis and L1-regression on the perceptions of 75 respondents, all senior executives and experts, through a survey. As regards the results of this study, critiques were formulated on the use of perceptions, often biased due to the political lobbying potential of the results. Since respondents often see independent studies as an opportunity to obtain more or early government subsidies, attract new investment projects or at least highlight the attention on their specific problems and demands, they were prone to underestimating the positive impact of the key success factors of the studied seaport compared to its main rivals, in this case major seaports in the so-called Hamburg–Le Havre competitive range. The purpose of this article is to test the assumption that respondents significantly underestimate the positive impact of port specific advantages and to see which of the respondent subgroups within the 75 respondents sample are more responsible than others for this underestimation. In addition, we argue and demonstrate that the use of a stochastic frontier method is appropriate for this matter. Each of 25 considered competition determinants of the original study is decomposed into a noise and “efficiency” term, based on the Bayesian stochastic frontier model (BSFM). In this article, we find evidence that BSFM could be used to test the “lobby-effect” or underestimation of the real effect of determinants, that terminal operators as a subgroup of respondents, are more likely to underestimate the key success factors than the subgroup of port experts and that those determinants that are directly related to government action show more underestimation than competitiveness determinants that result from private investments.  相似文献   

17.
Models of organizational management are presented in the literature and in the managerial practices of recent years. They are aimed to improve organizational governance, and to enhance organizational overall efficiency. The common denominator for most, if not all these management models is that they generally focus on a single aspect, or on a very limited number of aspects of the organizational conduct whereas running an organization is a highly complex undertaking, incorporating a large number of functions and processes. School principals tend to adapt out-of-school management process, usually adapting them from the business world. And therefore we can see that the educational system at all and the school system in particular, implement business management methods. This research indicates that school principals are well aware of all the school management processes and procedures. The important contribution of this research, which is based on the unique contribution of the multi-faceted theory, is acknowledging the work of the school principals as a pyramid which its base is composed of essential consensus procedures and its three sided indicate three major school management process. We suggest that this pyramid will be called “The Pyramid Model of School Management”. The various management processes that built this pyramid are based on mutual aims and consensus of the school team to reach these aims. The consensus of the aims is essential, and with out it, the school cannot exist as an affective organization. Choosing when to take a various management action is a feedback based, and situation-based conduct. It is also shown in this research that school principals distinguish between three major management processes which we recommend that they will be called the “pyramid sides” and include: results management, human resources management and general resources management. The three groups are bounded by the “core of management” which we recommend that will be called the “pyramid base”. The pyramid base is connected to each and every phase of the life cycle of the organization, to each process and each result. It includes the school targets and aims which all the school team has to agree upon and there must be an un-doubtful consensus about them.  相似文献   

18.
This paper examines the ways in which the number of item nonresponses is determined by social distance and/or interview rapport, with a focus on responses of “refusal” and “don’t know”, implying the respondent’s lack of willingness and ability to provide substantive responses to sensitive questions. The data analyzed were from 39 self- administered questions concerning sexual attitudes and behaviors in the 2002 Taiwan Social Change Survey for module “Family and Changing Gender Role”. Poisson Regression in 2-level Hierarchical Linear Model was employed to enhance the accuracy of the analysis of the accumulation of “don’t know” and “refusal” responses. The results showed that respondent cooperation significantly decreased the number of both “don’t know” and “refusal” replies. The decrease was not conditioned by any kind of social distance. Age and education distances have respectively negative and positive effect on the number of “don’t know” and “refusal” answers. The married–married interview produced more “don’t know” and “refusal” than other paired interview types. The larger the ethnicity distance is, the more “refusal” appears. The substantial findings imply that the effects of social-distance and rapport (respondent cooperation) on the number of item nonresponses deserve more attention in research on survey methodology. The divergent findings on gender-distance effect and marital-status effect, however, call for replication studies in the future.  相似文献   

19.
Consider an experiment involving the observation of a discrete random variable, or quantitative classification process. When, in addition to the probability of each value or class we know its “utility” (or, more precisely, we can quantify the “nature” of each value or class), the “uncertainty corresponding to the utilities” may be evaluated. In this paper, we are first going to introduce a family of Measures of Uncertainty involving Utilities and several properties of this family are studied. Then, some immediate applications are discussed: the definition of criteria for Comparing Experiments in Statistical Decision problems, and the quantification of the Inequality with respect to an economical attribute or the Industrial Concentration. Finally, we will analyze the asymptotic behaviour of the measures in simple random sampling, and some related problems. This work was partially supported by the Comisión Asesora de Investigación Científica Técnica (CAICYT) under the contract PB85-0401.  相似文献   

20.
Dr. Herbert Basler 《Metrika》1987,34(1):287-322
Summary The so-called Exact Test of R. A. Fisher for comparing two probabilitiesp 1 andp 2 in a Fourfold-Table with small cell frequencies is known as a UMPU-Test. But in practice the test is used in a nonrandomized, often tabulated version. Given a certain level of significanceα it is shown: the critical region of this nonrandomized test, referred to as “Fisher 1”, can be enlarged considerably. For instance for all sample-size-sums up to 20 andα=0.01 the total number of points in the critical regions of “Fisher 1” is 552 whereas the analogous number of the new version “Fisher 2” is 788. The size of tables for “Fisher 2” can be reduced considerably because the main parts of the critical regions can be described by the aid of some Chi-square-test versions. In particular Yates’ continuity-correction turns out to be always conservative in the above mentioned region relative to “Fisher 2” whereas this is not strictly true relative to “Fisher 1”.   相似文献   

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