Random Effects Misspecification Can Have Severe Consequences for Random Effects Inference in Linear Mixed Models

There has been considerable and controversial research over the past two decades into how successfully random effects misspecification in mixed models (i.e. assuming normality for the random effects when the true distribution is non‐normal) can be diagnosed and what its impacts are on estimation and inference. However, much of this research has focused on fixed effects inference in generalised linear mixed models. In this article, motivated by the increasing number of applications of mixed models where interest is on the variance components, we study the effects of random effects misspecification on random effects inference in linear mixed models, for which there is considerably less literature. Our findings are surprising and contrary to general belief: for point estimation, maximum likelihood estimation of the variance components under misspecification is consistent, although in finite samples, both the bias and mean squared error can be substantial. For inference, we show through theory and simulation that under misspecification, standard likelihood ratio tests of truly non‐zero variance components can suffer from severely inflated type I errors, and confidence intervals for the variance components can exhibit considerable under coverage. Furthermore, neither of these problems vanish asymptotically with increasing the number of clusters or cluster size. These results have major implications for random effects inference, especially if the true random effects distribution is heavier tailed than the normal. Fortunately, simple graphical and goodness‐of‐fit measures of the random effects predictions appear to have reasonable power at detecting misspecification. We apply linear mixed models to a survey of more than 4 000 high school students within 100 schools and analyse how mathematics achievement scores vary with student attributes and across different schools. The application demonstrates the sensitivity of mixed model inference to the true but unknown random effects distribution.     

Regulation and altruism

We study optimal contracts in a regulator–agent setting with joint production, altruistic and selfish agents, limited liability, and uneasy outcome measurement. Such a setting represents sectors of activities such as education and healthcare provision. The agents and the regulator jointly produce an outcome for which they all care to some extent that is varying from agent to agent. Some agents, the altruistic ones, care more than the regulator does while others, the selfish agents, care less. Moral hazard is present due to both the agent's effort and the joint outcome that are not contractible. Adverse selection is present too since the regulator cannot a priori distinguish between altruistic and selfish agents. Contracts consist of a simple transfer from the regulator to the agents together with the regulator's input in the joint production. We show that, under the conditions of our setting and when we face both moral hazard and adverse selection, the regulator maximizes welfare with a menu of contracts, which specify higher transfers for the altruistic agents and higher regulator's inputs for the selfish agents.     

Optimal regulation under imperfect enforcement: Permits,tickets, or both?

Economic activity is often regulated through both permits and tickets (subsequent inspections). We study the effectiveness of such policies where corruption and an underground economy make enforcement imperfect. In the theoretical model, asymmetric information justifies regulatory action which is enforced by corruptible bureaucrats. We find that regulation through permits alone is useless when corruption exists, while tickets still offer some benefit. Surprisingly, we also find that a system with both permits and tickets achieves welfare that is higher than that which can be achieved with only tickets—that combining the two mechanisms has an effect that is greater than the “sum of the parts.”     

Have SFAS 166 and SFAS 167 improved the financial reporting for securitizations?

Critics have alleged that securitization accounting prior to 2010 was among the causes of the recent financial crisis. In response to this criticism, the Financial Accounting Standards Board (FASB) implemented two new accounting standards, SFAS 166 and SFAS 167, to improve the financial reporting for securitizations. Bank regulators have stated their belief that SFAS 166/167 will result in a consolidated balance sheet (and risk-based capital ratios based thereupon) that better reflects a bank's exposure to risk related to securitized assets. We document that, by ceding retained power or influence through the servicing/special servicing functions to third parties, SFAS 166/167 resulted in real effects to the extent that banks (particularly those that were weakly capitalized) achieved their accounting objectives in the post-SFAS 166/167 period through legitimate transaction structuring in line with the intent of the new rules. Further, we use capital market participants’ assessments of risk retention by sponsoring banks as a benchmark, and provide evidence consistent with bank regulators’ beliefs. In particular, following SFAS 166/167, equity investors of sponsoring banks do not consider (consider) as risk relevant securitized assets that receive off-balance sheet (on-balance sheet) treatment. Securitized assets that are consolidated under SFAS 166/167 exhibit the same risk relevance as assets that are not securitized, despite contractual provisions that would seem to imply substantial risk transfer.     

Green human resource management and the enablers of green organisational culture: Enhancing a firm's environmental performance for sustainable development

Scholars have shown that green human resource management (GHRM) practices enhance a firm's environmental performance. However, existing studies fail to explain how GHRM initiatives can enable a green organisational culture or how such a culture affects the environmental performance and sustainable development of the firm. This paper examines the relationship between GHRM practices, the enablers of green organisational culture, and a firm's environmental performance. We conduct a large‐scale survey of 204 employees at Chinese manufacturing firms. Our findings suggest that proenvironmental HRM practices including hiring, training, appraisal, and incentivisation support the development of the enablers of green organisational culture. We suggest the key enablers of green organisational culture include leadership emphasis, message credibility, peer involvement, and employee empowerment. Our paper contributes to HRM theory in terms of originality and utility of research by explaining that the enablers of green organisational culture positively mediate the relationship between GHRM practices and environmental performance. Managers are provided with a detailed understanding of the GHRM practices needed to enable an organisational culture of environmentally aware employees. Finally, we address potential implications of this work for teaching green organisational culture to future generations of responsible managers.     

Sociological Models Based on Fréchet Random Variables

Products of random variables are of both practical and theoretical significance to social scientists. This has increased the need to have available the widest possible range of statistical results on products of random variables. In this note, the distribution of the product XY is derived when X and Y are independent Fréchet random variables. Extensive tabulations of the associated percentage points are also given.     

One Share - One Vote: the Theory

The theoretical literature on security-voting structure canbe organized around three questions: What impact do nonvotingshares have on takeover outcomes? How does disproportional votingpower affect the incentives of blockholders? What are the repercussionsof mandating one share - one vote for firms' financing and ownershipchoices? Overall, the costs and benefits of separating cashflow and votes reflect the fundamental governance trade offbetween disempowering blockholders and empowering managers.It is therefore an open question whether mandating one share- one vote would improve the quality of corporate governance,notably in systems that so far relied on active owners.     

Effects of farm credit access on agricultural commercialization in Ghana: Empirical evidence from the northern Savannah ecological zone

The purpose of this paper is to investigate how farmers' access to credit affects agricultural commercialization in the northern Savannah ecological zone of Ghana. The study uses data from the Ghana Feed the Future baseline survey involving a total sample of 2,962 farm households. The study employs endogenous switching regression for ordered outcomes to account for endogeneity and self‐selection bias in the decision to access credit. The results from the estimations revealed that education, age, nonfarm business equipment, multiple crop production, and group membership are the variables influencing farmers' access to credit. Agricultural commercialization is determined by gender, age, marital status, household size, farm size, nonfarm business equipment, means of transport, group membership, assets index, multiple crop production, and location. In terms of causal effect, the results show that credit access stimulates higher commercialization. Thus policies that enhance farmers' access to credit are more likely to be successful in getting them to commercialize.     

Modelling the Ecological Comorbidity of Acute Respiratory Infection,Diarrhoea and Stunting among Children Under the Age of 5 Years in Somalia

The aim of this study was to assess spatial co‐occurrence of acute respiratory infections (ARI), diarrhoea and stunting among children of the age between 6 and 59 months in Somalia. Data were obtained from routine biannual nutrition surveys conducted by the Food and Agriculture Organization 2007–2010. A Bayesian hierarchical geostatistical shared component model was fitted to the residual spatial components of the three health conditions. Risk maps of the common spatial effects at 1×1 km resolution were derived. The empirical correlations of the enumeration area proportion were 0.37, 0.63 and 0.66 for ARI and stunting, diarrhoea and stunting and ARI and diarrhoea, respectively. Spatially, the posterior residual effects ranged 0.03–20.98, 0.16–6.37 and 0.08–9.66 for shared component between ARI and stunting, diarrhoea and stunting and ARI and diarrhoea, respectively. The analysis showed clearly that the spatial shared component between ARI, diarrhoea and stunting was higher in the southern part of the country. Interventions aimed at controlling and mitigating the adverse effects of these three childhood health conditions should focus on their common putative risk factors, particularly in the South in Somalia.     

The impact of narrative disclosure readability on bond ratings and the cost of debt

Prior research on the determinants of credit ratings has focused on rating agencies’ use of quantitative accounting information, but the there is scant evidence on the impact of textual attributes. This study examines the impact of financial disclosure narrative on bond market outcomes. We find that less readable financial disclosures are associated with less favorable ratings, greater bond rating agency disagreement, and a higher cost of debt. We improve causal identification by exploiting the 1998 Plain English Mandate, which required a subset of firms to exogenously improve the readability of their filings. Using a difference-in-differences design, we find that the firms required to improve the readability of their filings experience more favorable ratings, lower bond rating disagreement, and lower cost of debt. Collectively, our evidence suggests that textual financial disclosure attributes appear to not only influence bond market intermediaries’ opinions but also firms’ cost of debt.