Design of an interrelated quality system for a single product manufacturing process with assembly

The design of a single product manufacturing system with assembly is considered. The processing is on a lot-by-lot basis with the lot size fixed. The decision variables include interrelated single sampling plans, manufacturing process quality levels, incoming raw material quality levels and assembly process quality levels. A solution procedure is given to minimize the expected total of the costs associated with the quality of the finished product subject to a limit on the Average Outgoing Quality Limit of the finished product. An example is provided.     

The Bias Due to Omitting Income When Estimating Demand Functions

This paper obtains an expression of the bias when relevant explanatory variables are omitted in seemingly unrelated regression (SUR) models. A simple demand system is provided to illustrate the direction of the bias terms when a variable is omitted.
L'article permet d'exprimer le biais qui résulterait de l'omission de variables explicatives pertinentes dans des modéles de régression sans corrélation apparente (SUR). Le système de demande simple qui est présente ici met en évidence le sens des éléments de biais lorsqu'on omet une variable.     

A new test for D-stability

A sufficient condition for D-stability of an n × n matrix A is the existence of a positive diagonal matrix P such that PA + A′P is negative definite. The search for P is replaced by solving a convex minimization problem.     

Optimal Management of Soil Quality Stocks and Long-Term Consequences of Land Degradation for Smallholder Farmers in Malawi

While soil degradation has long-term consequences, static models which form the bulk of studies on this topic in Africa, do not account for the inter-temporal dimensions of optimal resource management. This paper used an inter-temporal optimisation framework, which considered soil in a time-dependent resource extraction perspective. We have demonstrated that soil degradation is causing an enormous reduction in productive value of smallholder land in Malawi. Current user cost of soil quality among smallholder farmers, which represents annual loss in productive value of land, was estimated to be US$21 per hectare. Based on this value and land area under smallholder agriculture in Malawi, economic costs of soil degradation among smallholder farmers were estimated to amount to 14% of the agricultural GDP for Malawi. Although smallholder farmers’ current practices are sub-optimal to Steady State solutions, they are above static solutions. This demonstrates that smallholder farmers have some private incentives to invest in the soil quality stock. Smallholder farmers internalise some of the dynamic costs of soil degradation under the current practices. However, a sensitivity analysis on a slightly higher discount rate indicates that SS solutions closely resemble the prevailing smallholder farming practices. This suggests that smallholder farmers may be overexploiting soil quality stock because they have a high time preference. That is, they value the current consumption more than their future consumption and wellbeing. High levels of poverty in Malawi and serious lack of viable alternatives to subsistence farming may be influencing such behaviour. Promoting more viable land use alternatives than subsistence farming and formuling policies that help transform smallholder agriculture into a profitable enterprise will not only increase the cost of degrading the soil, but also encourage farmers to invest in the soil quality stock.     

Forecasting value‐at‐risk in oil prices in the presence of volatility shifts

Recent evidence suggests shifts (structural breaks) in the volatility of returns causes non‐normality by significantly increasing kurtosis. In this paper, we endogenously detect significant shifts in the volatility of oil prices and incorporate this information to estimate Value‐at‐Risk (VaR) to accurately forecast large declines in oil prices. Our out‐of‐sample performance results indicate that the model, which incorporates both time varying volatility (without making any distributional assumptions) and shifts in volatility, produces more accurate VaR forecasts than several benchmark methods. We make a timely contribution as the recent more frequent occurrences of unexpected large oil price declines has gained significant attention because of its substantial impact on the financial markets and the global economy.     

Does ethics improve stock market resilience in times of instability?

This paper compares the resilience of ethical (Islamic and socially responsible) indexes among five developed (US, UK, Japan, Canada, Australia) and three emerging markets (Brazil, India, South Africa) during the period following the 2008 subprime crisis. It relies on a multivariate CAPM-EGARCH model that accounts for sudden changes in volatility through the application of an iterated cumulative sums of squares (ICSS) algorithm on daily data over the sample period 2008–2014 to model time-varying volatility and ensure reliable estimates. The study confirms the lower systemic risk associated with Islamic indexes during the bearish period and reports that SRI, despite being more subject to systemic risk, offered higher alphas in highly integrated markets, while Islamic indexes performed better in less integrated ones. The evidence also reveals a very limited increase in the models’ predictability power from the integration of sudden changes in volatility into the EGARCH models during the full sample period. This limit is more marked during the bearish sub-period. Our findings have important implications for international investment and portfolio diversification perspectives in times of financial downturn.     

The impact on stock prices of deferral and elimination of internal control audit requirement for small firms

This paper examines the cumulative market reaction to the events related to deferral of internal control audit requirement under the Sarbanes-Oxley Act of 2002 and its elimination under the Dodd-Frank Act of 2010 for nonaccelerated filers (small firms). We document that small firms experienced negative cumulative abnormal returns around these events; and the differences between the cumulative abnormal returns for small firms and the two control groups (accelerated and large accelerated filers) were negative and significant at the 1% level. These results support the notion that market participants value the reliability of financial information irrespective of the firm size. Within the small firms, we find no firm characteristic significantly explains the market reaction to the events considered. That is, all small firms lost market value in reaction to the events that delayed and eliminated their internal control audit requirement.     

Bibliometric and Scientometric analysis on CSR practices in the banking sector

This paper provides a bibliometric and Scientometric analysis of the corporate social responsibility (CSR) in banking sector. Our study analyzes 551 articles from the Scopus database to find out the relationship between CSR and banking. A bibliometric method was used to visualize the results using R-studio and VOS viewer software. The Scientometric analysis was conducted to determine the findings and mappings of the research themes, directions of current and future research, impact, co-occurrence, co-citations and impact and collaboration trends. We explore how CSR literature has evolved over the years in the banking sector between 1993 and 2021. We find that publication in the CSR and banking domain has increased significantly during 2017 and 2021. Social aspects, board of directors, CSR, environment, competitions, Islamic banking, sustainability, disclosure, ethics, legitimacy theory, sustainable banking, loyalty, and brand equity are the popular research trends and collaboration trends identified. We also provide further scope of the study based on the extensive review of the past literature. Our findings may provide help to future researchers, bankers, and regulators in understanding the current trends and future research progression in the CSR and banking sector.     

How career plateau beliefs and leader interpersonal unfairness harm job performance in dysfunctional organizational settings

Building on social exchange theory and attribution theory, this study unpacks the relationship between employees' perceptions of organizational politics and job performance, considering the mediating effect of career plateau beliefs and the moderating effect of leader interpersonal unfairness. The findings provide empirical support for the theoretical predictions. An important reason for which perceptions of dysfunctional organizational politics reduce job performance is that employees develop beliefs that opportunities for their career development are limited. This mediating role of career plateau beliefs is particularly salient to the extent that employees are exposed to organizational leaders who treat them with disrespect. Organizations can mitigate the risk that highly politicized decision-making processes lead to negative performance outcomes by stimulating fair interpersonal relationships.     

Personality and balanced psychological contracts: The mediating roles of epistemic curiosity and rule‐following behavior

This study extends prior research on the relationships between personality constructs and types of psychological contracts by exploring how the Big Five traits predict balanced psychological contracts. Further, we determine whether epistemic curiosity and rule‐following behavior are key mediators of the proposed relationships. We tested our proposed hypotheses using three‐wave time‐lagged data from 469 respondents. The results indicated that openness to experience was positively associated and both conscientiousness and neuroticism were negatively associated with balanced contracts. Extraversion and agreeableness were not associated with balanced contracts. We also established the mediating role of epistemic curiosity in the relationships between personality traits and balanced contracts, but there was no support for the mediating role of rule‐following behavior in the present study. These findings have important implications for managers and organizations in terms of selecting the right person for a job (person‐job fit) and ensuring employee retention (person‐organization fit), hence having a bottom‐line effect on firm performance. Future research directions are also discussed.