An investigation of transformation-based prediction interval for the Weibull median life

Statistical inference based on the Weibull distribution, a distribution widely used in reliability and survival analysis, is usually difficult as it often involves numerical computation and approximation. However, this distribution can be transformed to near-normality by a simple power transformation. Based on this transformation, a prediction interval (PI) for its median can be easily constructed through an inverse transformation. The procedure for selecting the best power transformation through minimizing Kullback-Leibler information is described. The property of this transformation-based PI is investigated. Simple correction factors are also proposed. It is shown that the transformation-based PI with corrections performs well, irrespective of the sample size and parameter values. Simulation results show that the new PI generally outperforms the existing PI. Numerical examples are given for illustration.     

More thinking on research methods for the resource‐based perspective

We re‐examine the benefits of using a broader set of research methods to address key questions associated with the resource‐based view (RBV) of the firm. In responding to Levitas and Chi, we consider how research inside organizations can complement and augment research relying on secondary data. Copyright © 2002 John Wiley & Sons, Ltd.     

Job change and workplace learning in the public sector: the significance of new technology for unskilled work

Focussing here on local authorities and health services, this paper examines the significance of new technology to unskilled work in the public sector as it is developing and the implications for workplace learning. An argument is developed that new technology is central to a minority of examples of job change, although, significantly, it is more important to staff–initiated change and to workers' ability to fully participate in life beyond the workplace.     

Improved estimation of portfolio value‐at‐risk under copula models with mixed marginals

Portfolio value‐at‐risk (PVAR) is widely used in practice, but recent criticisms have focused on risks arising from biased PVAR estimates due to model specification errors and other problems. The PVAR estimation method proposed in this article combines generalized Pareto distribution tails with the empirical density function to model the marginal distributions for each asset in the portfolio, and a copula model is used to form a joint distribution from the fitted marginals. The copula–mixed distribution (CMX) approach converges in probability to the true marginal return distribution but is based on weaker assumptions that may be appropriate for the returns data found in practice. CMX is used to estimate the joint distribution of log returns for the Taiwan Stock Exchange (TSE) index and the associated futures contracts on SGX and TAIFEX. The PVAR estimates for various hedge portfolios are computed from the fitted CMX model, and backtesting diagnostics indicate that CMX outperforms the alternative PVAR estimators. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:997–1018, 2006     

Finance as a Barrier to Entry: Bank Competition and Industry Structure in Local U.S. Markets

This paper tests how competition in local U.S. banking markets affects the market structure of nonfinancial sectors. Theory offers competing hypotheses about how competition ought to influence firm entry and access to bank credit by mature firms. The empirical evidence, however, strongly supports the idea that in markets with concentrated banking, potential entrants face greater difficulty gaining access to credit than in markets in which banking is more competitive.     

Marketplace and personal space: Investigating the differential effects of attachment style across relationship contexts

An individual's tendencies in purely personal relationships seem to lead to related tendencies in consumer relationships. The following article presents a study that illustrates how individual differences in personal relationship attachment style can be used to predict the likely success of consumer relationships. In addition, it illustrates how the success of consumption versus nonconsumption relationships can be explained by the effect of attachment style on the individual's perception of qualities of the relationship. © 2006 Wiley Periodicals, Inc.     

Initial Public Offerings: CFO Perceptions

We examine four issues pertaining to initial public offerings (IPOs) using a survey of 438 chief financial officers (CFOs). First, why do firms go public? Second, is CFO sentiment stationary across bear and bull markets? Third, what concerns CFOs about going public? Fourth, do CFO perceptions correlate with returns? Results support funding for growth and liquidity as the primary reasons for IPOs. CFO sentiment is generally stationary in pre‐ and post‐bubble years. Managers are concerned with the direct costs of going public, such as underwriting fees, as well as indirect costs. We find a negative relation between a focus on immediate growth and long‐term abnormal returns.