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1.
S. Bagchi 《Metrika》1988,35(1):1-12
In a situation where the given set of parameters (b, k andv) precludes the existence of any known optimal block designs, but an optimal block design is known to exist with parametersb, k andv*>v, a new design is shown to be useful. This (b, k, v) design is obtained from the (b, k, v*) optimal design by collapsing the classes of a suitable paritition of the treatment set (of the latter design) to treatments (of the former). We call the new design a quotient of the original design. Although the quotient is non binary and unequally replicated, it turns out to beE-optimal within the class of all proper and connected designs withb, k andv, provided the replication number of the optimal design we start with is not too large.  相似文献   

2.
Zimmer (‘The role of copulas in the housing crisis’, Review of Economics and Statistics 2012; 94 : 607–620) provides an interesting case study of the pitfalls of using parametric copulas to understand the US housing crisis in the latter part of 2000s. The original study by Zimmer (2012) employs a finite‐mixture copula to illustrate that the symmetry of the Gaussian copula may not be tenable, especially for US housing price data during the time period from 1975:Q2 to 2009:Q1. We undertake a replication of his study in a wide sense. First, we replicate the study by incorporating revised data and then extending the dataset to include the most recent data. Second, we implement a nonparametric copula estimator recently proposed by Racine (‘Mixed data kernel copulas’, Empirical Economics forthcoming) to the parametrically filtered data used in Zimmer (2012). Our replication finds that the application of the nonparametric copula to the same and extended filtered data provides an alternative flexible specification for copulas. However, the overall cautionary message of the flexible‐form copula espoused in Zimmer (2012) remains. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

3.
This note provides a narrow replication of Fisman and Miguel's (Journal of Political Economy, 2007a; 115 (6): 1020–1048) original findings about estimating negative binomial count models to study corruption practices among United Nations diplomats. We present estimates based on zero‐inflated count models, given the possible presence of excessive zero counts in the dependent variable of the main specifications. Our results confirm Fisman and Miguel's original findings. However, they also suggest the importance of considering distinct generating processes for zero outcomes. We cannot reject hypotheses favoring the use of zero‐inflated negative binomial models over its simpler versions in this context. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

4.
The Hannah-Kay [1977] generalized concentration index contains the well-known Herfindahl [1950]-Hirschman [1945] and the entropy indices as particular cases. In this papaer we show that the Hannah-Kay class can be regarded as a particular member of a generalized family of indices, which we refer to as self-weighted quasilinear means. We then show that among all self-weighted quasilinear means the Hannah-Kay family is the only class of concentration indices which satisfies the replication principle, a requirement which states that an m-fold replication of the industry, firm by firm, will multiply the concentration index by the factor 1/m.The refereeing process of this paper was handled through N.R. Adam.We are grateful to two anonymous referees for their suggestions.  相似文献   

5.
We examine how price impact in the underlying asset market affects the replication of a European contingent claim. We obtain a generalized Black–Scholes pricing PDE and establish the existence and uniqueness of a classical solution to this PDE. Unlike the case with transaction costs, we prove that replication with price impact is always cheaper than superreplication. Compared to the Black–Scholes case, a trader generally buys more stock and borrows more (shorts and lends more) to replicate a call (put). Furthermore, price impact implies endogenous stochastic volatility and an out-of-money option has lower implied volatility than an in-the-money option. This finding has important implications for empirical analysis on volatility smile.  相似文献   

6.
The present paper re-analyzes and extends a study on institutional forces and the written business plan (Honig and Karlsson in J Manag 30(1):29–48, 2004). We attempt to examine to what extent critical decision making is evident in model and variable choice, and whether the implications provided by systematic replication efforts may serve to provide additional and perhaps unrecognized theoretical and/or empirical observations. We find that the key result—formal business planning does not affect performance, does not hold. In fact, we find evidence that formal business planning affects survival but not profitability. The re-analysis also reveals, that institutional antecedents to formal planning appear to be fragile and prone to researcher biases due to different coding and assumptions. Our study underscores the consequences of access to original data and coding material, and to rely upon current methodological explanations for subsequent analyses.  相似文献   

7.
The welcome rise of replication tests in economics has not been accompanied by a consensus standard for determining what constitutes a replication. A discrepant replication, in current usage of the term, can signal anything from an unremarkable disagreement over methods to scientific incompetence or misconduct. This paper proposes a standard for classifying one study as a replication of some other study. It is a standard that places the burden of proof on a study to demonstrate that it should have obtained identical results to the original, a conservative standard that is already used implicitly by many researchers. It contrasts this standard with decades of unsuccessful attempts to harmonize terminology, and argues that many prominent results described as replication tests should not be described as such. Adopting a conservative standard like this one can improve incentives for researchers, encouraging more and better replication tests.  相似文献   

8.
Statistical agencies often release a masked or perturbed version of survey data to protect the confidentiality of respondents' information. Ideally, a perturbation procedure should provide confidentiality protection without much loss of data quality, so that the released data may practically be treated as original data for making inferences. One major objective is to control the risk of correctly identifying any respondent's records in released data, by matching the values of some identifying or key variables. For categorical key variables, we propose a new approach to measuring identification risk and setting strict disclosure control goals. The general idea is to ensure that the probability of correctly identifying any respondent or surveyed unit is at most ξ, which is pre‐specified. Then, we develop an unbiased post‐randomisation procedure that achieves this goal for ξ>1/3. The procedure allows substantial control over possible changes to the original data, and the variance it induces is of a lower order of magnitude than sampling variance. We apply the procedure to a real data set, where it performs consistently with the theoretical results and quite importantly, shows very little data quality loss.  相似文献   

9.
We re-examine the importance of instruction time for student achievement on international assessments. We successfully replicate the positive effect of weekly instruction time in the seminal paper by Lavy (Economic Journal, 125, F397-F424) in a narrow sense. Extending the analysis to other international assessments, we find effects that are consistently smaller in magnitude. We provide evidence that this discrepancy might be partly due to a different way of measuring instruction time in the data used in the original paper. Our results suggest that differences in instruction time are less important than previously thought for explaining international gaps in student achievement.  相似文献   

10.
We provide an analytic and systematic review of the impact of March and Simon’s seminal Organizations on management research and discuss the book’s value for current research and propose future applications of it. Building on bibliometric and text‐mining approaches, our empirical analysis reveals that although Organizations was contextually based in the industrial milieu of the 1950s, its concepts have found ongoing resonance with scholars. Further, we find that much of this resonance appears to be driven by the ability of scholars in different ‘schools of thought’ to find useful insights from March and Simon’s generalized theoretical structure. However, we also observe that scholars have been selective in their usage of ideas from the book over the last 60 years. Based our analysis, we propose a particular set of future research areas, including a focus on new organizational forms and extending March and Simon’s ideas to multi‐level research, which can benefit from more holistically drawing on Organizations and connect its original ideas to address current management problems.  相似文献   

11.
We previously showed that ‘led by an invisible hand’ was physically central in original editions of The Theory of Moral Sentiments and The Wealth of Nations. We suggested that Adam Smith did that deliberately. Three authors commented on our paper, Gavin Kennedy, Ryan Hanley and Craig Smith. In this article we reply to their comments.  相似文献   

12.
The reproducibility crisis, that is, the fact that many scientific results are difficult to replicate, pointing to their unreliability or falsehood, is a hot topic in the recent scientific literature, and statistical methodologies, testing procedures and p‐values, in particular, are at the centre of the debate. Assessment of the extent of the problem–the reproducibility rate or the false discovery rate–and the role of contributing factors are still an open problem. Replication experiments, that is, systematic replications of existing results, may offer relevant information on these issues. We propose a statistical model to deal with such information, in particular to estimate the reproducibility rate and the effect of some study characteristics on its reliability. We analyse data from a recent replication experiment in psychology finding a reproducibility rate broadly coherent with other assessments from the same experiment. Our results also confirm the expected role of some contributing factor (unexpectedness of the result and room for bias) while they suggest that the similarity between original study and the replica is not so relevant, thus mitigating some criticism directed to replication experiments.  相似文献   

13.
We contribute to the body of literature on the what is beautiful is good heuristic (Dion, Berscheid, & Walster, 1972, Journal of Personality and Social Psychology, 24, 285–290), the beauty is beastly effect (Heilman & Saruwatari, 1979, Organizational Behavior and Human Performance, 23, 360–372) and lack of fit theory (Heilman, 1983, Research in Organizational Behavior, 5, 269–298) by reconciling previous discrepancies in the literature and by examining the circumstances in which attractiveness may and may not be detrimental for female job applicants. First, we perform a review of studies which have previously tested the beauty is beastly effect, and we provide and test explanations for previous discrepancies in the literature. Next, we conduct two new studies on the beauty is beastly effect using corporate types of jobs, and empirically test Heilman's lack of fit theory (1983) as an explanation for the effect. We find support for the effect in a general population sample, and partial support for the effect in a sample of human resource professionals. We also provide support for a mediated moderation model showing that applicant sex is related to job suitability for a male-typed job through the indirect effect of perceived agency, which is moderated by applicant attractiveness.  相似文献   

14.
In this article we reflect on our time as editors of JMS during the period 2003–09. First we describe the context as we saw it on assuming editorship of the Journal and the actions that we took to improve the quality of scholarship published in the journal in order to set JMS on the trajectory to become a world‐leading Journal. We articulate our view of what quality means in this context and observe that we eschewed the USA–Europe divide. Rather, to be publishable, all papers had to meet the highest standards relative to their epistemological assumptions. Finally, we address two important challenges facing the Journal, and indeed management research in general, and consider what they mean for the future of JMS, notably in relation to open access publishing and to provide greater practical relevance. We conclude that the latter represents a swing of the pendulum towards the kinds of papers published in the early years of JMS but that recent developments in JMS provide new conceptual frameworks and empirical methods that contribute to enhanced insights for practice.  相似文献   

15.
We consider the codifference and the normalized codifference function as dependence measures for stationary processes. Based on the empirical characteristic function, we propose estimators of the codifference and the normalized codifference function. We show consistency of the proposed estimators, where the underlying model is the ARMA with symmetric α-stable innovations, 0 < α ≤ 2. In addition, we derive their limiting distribution. We present a simulation study showing the dependence of the estimator on certain design parameters. Finally, we provide an empirical example using some stocks from Indonesia Stock Exchange.  相似文献   

16.
ABSTRACT

To allow for ‘multiple technologies’ to produce a homogeneous output in input–output models, Duchin and Levine [(2011) Sectors may use Multiple Technologies Simultaneously: The Rectangular Choice-of-technology Model with Binding Factor Constraints, Economic Systems Research, 23(3), 281–302] propose an optimization model constrained by primary resources. We show that the Duchin–Levine model contains two different mechanisms by which multiple technologies can arise. If a factor in short supply is shared by the original and the newly entering technology, the output of the original, lower-cost technology will be reduced to make room for the higher-cost technology which is less intensive in that factor. In contrast, if the factor in short supply is technology-specific, a higher-cost technology supplements the original lowest-cost one, which stays fully active. Either mechanism implies a mechanism-specific set of prices, quantities and rents. We relate these results to classical views on comparative advantage, fixed output levels and the origin of rents.  相似文献   

17.
When academic researchers, business commentators, and boards of directors have debated the merits of hiring new CEOs from outside the firm, the implicit or explicit assumption typically made is that outsider CEOs will provide an advantage in achieving strategic change. In this study, we challenge this assumption by employing a duality perspective on stability/change, and we provide an original conceptual framework to posit that it is the presence of corporate stability (ordinary succession, a long‐tenured predecessor CEO, and good firm performance) that allows outsider CEOs to generate a greater degree of post‐succession strategic change. We use extensive longitudinal data from US airline and chemical industries between 1972 and 2010 to test our hypotheses, and we discuss how our supportive findings challenge long‐standing assumptions regarding the outsider succession–strategic change relationship, and we advocate embracing the non‐intiutive notion that stable (unstable) conditions can be enablers (barriers) of strategic change for outsider CEOs.  相似文献   

18.
Using US fatality data from 1975 to 2003, Levitt (Evidence that seat belts are as effective as child safety seats in preventing death for children aged two and up, Review of Economics and Statistics 2008; 90 (1): 158–163) shows that child safety seats do not significantly reduce fatalities for children aged 2–6 years as compared to standard seat belts. Although we were unable to gain access to the original programs and dataset used, we were able to replicate Levitt's ( 2008 ) findings almost exactly. We extend Levitt ( 2008 ) by showing that the findings also hold for the years 2004–2011 despite changing driver characteristics and restraint use patterns. We fail to find evidence that SUVs provide additional safety for children. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

19.
In addition to their theoretical analysis of the joint determination of oil futures prices and oil spot prices, Alquist and Kilian (Journal of Applied Econometrics, 2010, 25(4), 539–573) compare the out‐of‐sample accuracy of the random walk forecast with that of forecasts based on oil futures prices and other predictors. The results of my replication exercise are very similar to the original forecast accuracy results, but the relative accuracy of the random walk forecast and the futures‐based forecast changes when the sample is extended to August 2016, consistent with the results of several other recent studies by Kilian and co‐authors.  相似文献   

20.
Phillips and Sul (Journal of Applied Econometrics 2009, 24 , 1153–1185) provide an algorithm to identify convergence clubs in a dynamic factor model of economic transition and growth. We provide a narrow replication of their key results, using the open source R software instead of the original GAUSS routines. We are able to exactly replicate their results on convergence clubs, corresponding point estimates and standard errors. We comment on minor differences between their reported results and their clustering algorithm. We propose simple adjustments of the original algorithm to make manual intervention unnecessary. The adjustments allow automated application of the algorithm to other data. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

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