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Meta-regression is widely used and misused today in meta-analyses in psychology, organizational behavior, marketing, management, and other social sciences, as an approach to the identification and calibration of moderators, with most users being unaware of serious problems in its use. The purpose of this paper is to describe nine serious methodological problems that plague applications of meta-regression.

This paper is methodological in nature and is based on well-established principles of measurement and statistics. These principles are used to illuminate the potential pitfalls in typical applications of meta-regression.

The analysis in this paper demonstrates that many of the nine statistical and measurement pitfalls in the use of meta-regression are nearly universal in applications in the literature, leading to the conclusion that few meta-regressions in the literature today are trustworthy. A second conclusion is that in almost all cases, hierarchical subgrouping of studies is superior to meta-regression as a method of identifying and calibrating moderators. Finally, a third conclusion is that, contrary to popular belief among researchers, the process of accurately identifying and calibrating moderators, even with the best available methods, is complex, difficult, and data demanding.

This paper provides useful guidance to meta-analytic researchers that will improve the practice of moderator identification and calibration in social science research literatures.

Today, many important decisions are made on the basis of the results of meta-analyses. These include decisions in medicine, pharmacology, applied psychology, management, marketing, social policy, and other social sciences. The guidance provided in this paper will improve the quality of such decisions by improving the accuracy and trustworthiness of meta-analytic results.

This paper is original and valuable in that there is no similar listing and discussion of the pitfalls in the use of meta-regression in the literature, and there is currently a widespread lack of knowledge of these problems among meta-analytic researchers in all disciplines.

Recently, we (Judiesch, Schmidt, & Mount, 1992) concluded that the Schmidt et al. (1979) SDy estimation procedure results in downwardly biased estimates of utility. This conclusion led us to propose a modification of the Schmidt et al. method that involves estimating SDy as the product of estimates of the coefficient of variation (SDy/ Y) and an objective estimate of the average value of employee output (Y). The present article reviews the rationale underlying our conclusion that this modification of the Schmidt et al. method of estimating SDy results in more accurate estimates of SDy, and hence, utility.

This study focused on analysing the effect of acquisition characteristics on post‐acquisition operating performance for 83 bids consisting of 83 public listed bidders acquiring 80 private, 2 public listed and 1 non‐public listed targets in Malaysia during the period 1988–1992. The specific bid characteristics analysed are business relatedness, management turnover, the relative size of targets to bidders, the method of payment offered and board of directors' ownership structure. Since the specific feature of the current sample is that it consists mainly of privately owned targets, the characteristics of disciplinary bids found in acquisitions of public listed targets were not expected in agreed bids between the bidders and targets in this study. The results indicate that the target directors' turnover and the directors' share ownership do not have a significant effect on the post‐acquisition performance. Rather it appears that, if anything, retention of existing management is more likely to lead to performance improvement. Further analysis shows that replacement of target management has no impact on post‐acquisition performance regardless of the relatedness line of business. The latter findings reinforce the unique characteristics of the data set used in the current analysis of acquisitions of privately owned Malaysian companies in which unique skills of previous directors may often be retained post‐acquisition regardless of the business relatedness. The study also provides evidence that acquisitions of highly related business between target and acquiring firm, large relative size of target to bidders and payment for the acquisition by shares have a significant positive impact on post‐acquisition control‐adjusted performance. However, highly related business between target and bidder and payment by shares are the only significant acquisition characteristics that have a significant positive impact on the post‐acquisition control‐adjusted performance when multiple regression is used.

The purpose of this paper is to find an optimized thin-film amorphous silicon solar cell design by numerically optimizing the light trapping efficiency of a pyramid-structured back-reflector using a frequency-domain finite element Maxwell solver. For this purpose short circuit current densities and absorption spectra within the investigated solar cell model are systematically analyzed. Furthermore, the authors employ a topology simulation method to accurately predict the material layer interfaces within the investigated solar cell model. The method simulates the chemical vapor deposition (CVD) process that is typically used to fabricate thin-film solar cells by combining a ballistic transport and reaction model (BTRM) with a level-set method in an iterative approach. Predicted solar cell models are far more realistic compared to solar cell models created assuming conformal material growth. The purpose of the topology simulation method is to increase the accuracy of thin-film solar cell models in order to facilitate highly accurate simulation results in solar cell design optimizations.

The authors perform numeric optimizations using a frequency domain finite element Maxwell solver. Topology simulations are carried out using a BTRM combined with a level-set method in an iterative fashion.

The simulation results reveal that the employed pyramid structured back-reflectors effectively increase the light path in the absorber mainly by exciting photonic waveguide modes. In using the optimization approach, the authors have identified solar cell models with cell periodicities around 480 nm and pyramid base widths around 450 nm to yield the highest short circuit current densities. Compared to equivalent solar cell models with flat back-reflectors, computed short circuit current densities are significantly increased. Furthermore, the paper finds that the solar cell models computed using the topology simulation approach represent a far more realistic approximation to a real solar cell stack compared to solar cell models computed by a conformal material growth assumption.

So far in the topology simulation approach the authors assume CVD as the material deposition process for all material layers. However, during the fabrication process sputtering (i.e. physical vapor deposition) will be employed for the Al:ZnO and ITO layers. In the framework of this ongoing research project the authors will extend the topology simulation approach to take the different material deposition processes into account. The differences in predicted material interfaces will presumably be only minor compared to the results shown here and certainly be insignificant relative to the differences the authors observe for solar cell models computed assuming conformal material growth.

The authors systematically investigate and optimize the light trapping efficiency of a pyramid nano-structured back-reflector using rigorous electromagnetic field computations with a 3D finite element Maxwell solver. To the authors’ knowledge such an investigation has not been carried out yet in the solar cell research literature. The topology simulation approach (to the best of the authors’ knowledge) has previously not been applied to the modelling of solar cells. Typically a conformal layer growth assumption is used instead.

The purpose of this study is to assess the digital preservation policies and plans for long-term digital preservation in selected repositories in South Africa, with a view to develop a digital preservation framework for the preservation of Indigenous knowledge system (IKS) in South Africa.

Through the multiple case study research design, data was obtained from eight respondents in four Indigenous Knowledge Systems Documentation Centers (IKSDCs) in institutions that are part of the National Recordal Systems (NRS) initiative across four provinces in South Africa using in-depth face-to-face interviews. Data collected was also supplemented with the content analysis of several policy documents in South Africa.

The findings reveal that there are no digital preservation policies in place in the institutions, especially long-term digital preservation for IKS. However, some of the institutions are formulating policies that will include the management of IKS collected in the institutions. This study also reveals that digital curation, policy formulation and disaster preparedness plans to some extent are measures said to be in place for the digital preservation of IKS.

This study focuses mainly on the NRS initiative in South Africa. Indigenous Knowledge (IK) related to traditional medicine, traditional plants and food are currently being digitized at the IKSDCs by IK recorders. This study will help in ensuring that the South African Government’s effort and investment in digitizing IKS and making them accessible online is not wasted. This study will help mitigate the risk of damage and alteration over time, either deliberately or in error.

This study fills a gap in the literature on the digitization and digital preservation of IKS from the context of the NRS project in South Africa. Very few studies have been carried out on the digital preservation of IKS in Africa. This study also proposed a framework for the digital preservation of IKS in South Africa.