Problems with detecting assumed mediation using the hierarchical multiple regression strategy

In human resource management (HRM) and allied fields (e.g., organizational behavior, management, and industrial and organizational psychology), tests of mediation are frequently conducted using the hierarchical multiple regression (HMR) strategy of Baron and Kenny [Baron, R. M., & Kenny, D. A. (1986). The moderator–mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations. Journal of Personality and Social Psychology, 51, 1173–1182]. Although previous research has identified a number of serious problems with this approach, the present study adds to the literature by identifying yet additional problems with its use in inferring the existence of mediation. Using a statistical simulation, we found that certain patterns of correlation coefficients guarantee inferences about mediation, whereas other patterns preclude such inferences. On the basis of various analyses including logistic regression and inspection of three-dimensional plots, we identified patterns of correlation coefficients needed to satisfy Baron and Kenny's [Baron, R. M., & Kenny, D. A. (1986). The moderator–mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations. Journal of Personality and Social Psychology, 51, 1173–1182] conditions for inferring mediation. The same patterns have no necessary relation to actual causal connections among variables in mediation models. Moreover, as a consequence of the failure of the HMR strategy to detect mediating effects, many instances of actual mediation in HRM and allied fields may have gone undetected. In view of the foregoing, we conclude that the HMR strategy should no longer be used in testing for mediation.     

Poisson Regression for Clustered Data

We compare five methods for parameter estimation of a Poisson regression model for clustered data: (1) ordinary (naive) Poisson regression (OP), which ignores intracluster correlation, (2) Poisson regression with fixed cluster‐specific intercepts (FI), (3) a generalized estimating equations (GEE) approach with an equi‐correlation matrix, (4) an exact generalized estimating equations (EGEE) approach with an exact covariance matrix, and (5) maximum likelihood (ML). Special attention is given to the simplest case of the Poisson regression with a cluster‐specific intercept random when the asymptotic covariance matrix is obtained in closed form. We prove that methods 1–5, except GEE, produce the same estimates of slope coefficients for balanced data (an equal number of observations in each cluster and the same vectors of covariates). All five methods lead to consistent estimates of slopes but have different efficiency for unbalanced data design. It is shown that the FI approach can be derived as a limiting case of maximum likelihood when the cluster variance increases to infinity. Exact asymptotic covariance matrices are derived for each method. In terms of asymptotic efficiency, the methods split into two groups: OP & GEE and EGEE & FI & ML. Thus, contrary to the existing practice, there is no advantage in using GEE because it is substantially outperformed by EGEE and FI. In particular, EGEE does not require integration and is easy to compute with the asymptotic variances of the slope estimates close to those of the ML.     

Managerial perceptions of service-infused IORs in China & India: A discursive view of value co-creation

This paper explores the managerial challenges facing firms seeking to build relationships with other network actors while doing business in foreign markets. By taking a critical perspective on an area of increasing importance in both manufacturing and service sectors, that of value co-creation, the paper explores how managers in different cultural contexts make sense of the notion of ‘value’ in inter-organizational B2B relationships between New Zealand service and service-infused supplier firms and buyers in China and India. From an analysis of the interview-based accounts on both sides of the buyer–seller dyad marked differences emerge regarding value-creation within managers' discourse around partnerships, collaboration and cooperation. Our findings suggest that the Indian manager's discursive use of ‘partnership’ draws on service-dominant logic in viewing this type of interaction as a means for co-creating value; they and their New Zealand suppliers are jointly involved in co-creating value within a service system, creating value-in-use. In contrast, the predominant perspective seen in the discourse of Chinese managers is the use of cooperation as a means of making transactions more cost-effective, or to fill gaps in their supply chains, resulting in the creation of transaction-based, co-production of value, which suggests a value-in-exchange orientation. In both cases, there is repeated reference to more peripheral actors whose efforts result in what we interpret as network value creation, based on their interactions with actors within the buyer–seller dyad.     

Plant Scale and Exchange‐Rate‐Induced Productivity Growth

This paper examines the impact of exchange rate movements on firm‐level productivity through changes in the scale of production. We employ plant‐level data to examine whether, and in what direction, exchange rate movements affect the scale of production, and how these changes in scale influence productivity. The paper finds that a real appreciation of the domestic currency reduces shipments and this negative effect is larger for exporters (both domestic and foreign owned). The paper also finds evidence that the appreciation‐induced reduction of scale negatively affects productivity at the plant level. This scale effect more than offsets any potential gains from the appreciation‐induced reduction in the price of imported inputs.     

Do small shareholders count?

We hypothesize that age similarity among small shareholders acts as an implicit coordinating device for their actions and, thus, could represent an indirect source of corporate governance in firms with dispersed ownership. We test this hypothesis on a sample of Swedish firms during the 1995-2000 period. Consistent with our hypothesis, we find that compared with shareholders of differing ages, same-age noncontrolling shareholders sell more aggressively following negative firm news; firms with more age-similar small shareholders are more profitable and command higher valuation; and an increase (decline) in a firm's small shareholder age similarity brings a significantly large increase (decline) in its stock price. The last effects are more pronounced in the absence of a controlling shareholder.     

Foreign investment in Russia and China: A long way to go,but reason for optimism

D. LeBaron, with D. Carpenter. 2002. Mao, Marx, and the Market: Capitalist Adventures in Russia and China. New York: John Wiley & Sons, Inc. 303 pages; ISBN: 0‐471‐15315‐X. B. Granville & P. Oppenheimer (Eds.). 2001. Russia's Post‐Communist Economy. Oxford, England: University Press. 538 pages; ISBN 0‐19‐829525‐1. H. Fung & K.H. Zhang (Eds.). 2002. Financial Markets and Foreign Direct Investment in Greater China. New York: M.E. Sharpe, Inc. 302 pages; ISBN: 0‐7656‐0804‐9.     

Attitudes toward ethics: A view of the college student

This study investigated the differences in responses of undergraduate business students to an ethical dilemma. Demographic characteristics were collected on the respondents and profiled as a means of examining common bases for decision. The authors found that certain demographic characteristics appear to be predictors of ethical decision behavior of future businessmen.Eugene W. Grant, Jr. is Accounting Professor at Samford University. He has published several books as well as numerous articles. One of his areas of research interest is the predicability of ethical decision behavior in potential employees. Prior to joining academia, he was a consultant with the firm of Ernst & Whinney.Lowell Broom is the Dwight Moody Beeson Professor of Accounting at Samford University, Birmingham, Alabama. Professor Broom received his DBA in Accounting from Louisiana Tech University and is a CPA. He has previously served on the faculty of Baylor University and was employed by Ernst & Whinney prior to entering teaching.