Do optimal diversification strategies outperform the 1/N strategy in U.K. stock returns?

This paper examines whether optimal diversification strategies outperform the 1/N strategy in U.K. stock returns. The study focuses on the performance of recent strategies developed by Tu and Zhou (2011) and Kirby and Ostdiek (2010). I find that a number of optimal asset allocation strategies can significantly outperform the 1/N strategy even after adjusting for trading costs. The strategies developed by Kirby and Ostdiek outperform the 1/N strategy, even at higher trading costs, due to the low turnover of these strategies. The strategies of Tu and Zhou have mixed performance after adjusting for trading costs due to the high turnover of these strategies. The results of the paper provide support for the use of optimal diversification strategies.     

Disentangling location-based advertising: the effects of location congruency and medium type on consumers' ad attention and brand choice

Research on location-based advertising (LBA) suggests that the merits of LBA lie in the fact that consumers can be targeted with location-congruent ads on their personal mobile devices. However, LBA consists of two underlying constructs: a mobile (vs. point-of-sales) advertising medium and location congruency (vs. location incongruency). This study aims to disentangle these underlying constructs by showing that they differentially affect the efficacy of an ad. Using a virtual reality lab experiment, this study shows that location-congruent ads result in increased choice for the target brand as compared to location-incongruent ads, independent of medium type. However, in location-incongruent situations, mobile ads attracted more attention than point-of-sales display ads. The advantages of LBA thus do not seem to emanate from medium type, but rather from the congruency between the ad and product location. When the ad is received at a different location than the product, the mobile medium is able to enhance consumers' ad attention.     

Analysing enterprise architecture maturity models: a learning perspective

In order to aid organisations in the adoption of enterprise architecture (EA) best practices, maturity models have been proposed in the literature. These models offer organisational roadmaps and assessment frameworks for increasing EA maturity. However, key questions concerning the implied meaning of the term maturity in the context of these models have been left unexplored by previous research. This research, aided by the field of organisational learning, offers new insights into the implied assumptions of current EA maturity models and offers initial concepts and constructs to guide the conceptualisation, construction and refinement of enterprise maturity models.     

Birth,death and public good provision

We explore the effect of fixed versus dynamic group membership on public good provision. In a novel experimental design, we modify the traditional voluntary contribution mechanism (VCM) by periodically replacing old members of a group with new members over time. Under this dynamic, overlapping generations matching protocol we find that average contributions experience significantly less decay over time relative to a traditional VCM environment with fixed group membership and a common termination date. These findings suggest that the traditional pattern of contribution and decay seen in many public goods experiments may not accurately reflect behavior in groups with changing membership, as is the case in many real-world environments.     

Banks and Microbanks

We combine two datasets to examine whether the presence of banks affects the profitability and outreach of microfinance institutions. We find evidence that competition matters. Greater bank penetration in the overall economy is associated with microbanks pushing toward poorer markets, as reflected in smaller average loans sizes and greater outreach to women. The evidence is particularly strong for microbanks relying on commercial-funding and using traditional bilateral lending contracts (rather than group lending methods favored by microfinance NGOs). We consider plausible alternative explanations for the correlations, including relationships that run through the nature of the regulatory environment and the structure of the banking environment, but we fail to find strong support for these alternative hypotheses.     

Exploring Value‐Based Management Sophistication: The Role of Potential Economic Benefits and Institutional Influence

The complexity of value‐based management (VBM) is often not captured in empirical research. In particular, potential differences in the extent of VBM implementation are not considered. Firms are predominantly classified dichotomously into either VBM “adopters” or “non‐adopters.” In this study, we aim to fill this gap by introducing a framework to assess differences in the extent of VBM implementation (VBM‐sophistication) based on publicly available data. This approach enables us to study determinants of VBM‐sophistication based on a hand‐collected data set comprising 2,683 firm‐year observations from 16 European countries between 2005 and 2014. Specifically, we investigate (i) whether potential economic benefits associated with VBM implementation lead to a higher level of VBM‐sophistication, and (ii) if this relation is influenced by extra‐organizational institutions (e.g., industry norms). Our results indicate that companies exhibit higher VBM‐sophistication if certain firm characteristics that increase the potential economic benefits of VBM are present. Moreover, our study provides evidence that this effect is enhanced by extra‐organizational institutions that pressure and support firms in realizing the potential benefits of higher VBM‐sophistication.     

Climate change adaptation actions by fish farmers: evidence from the Niger Delta Region of Nigeria

This paper examined climate change adaptation strategies in fish farming and the effect of such methods on the profit of fish farmers in the Niger Delta region of Nigeria, Africa’s most populous country. Using cross‐sectional data obtained from 420 fish farmers from the region and applying multivariate probit and instrumental variable regressions, the study found that fish farmers have adopted a broad range of strategies to address climate risk and that these have significantly increased farmers’ profit. Our findings indicated important relationships between certain farm, socio‐economic and institutional characteristics and the adaptation actions. The study provides useful insight into factors that potentially encourage the adoption of livelihood‐enhancing climate risk adaptation strategies by fish farmers in the Niger Delta region and similar contexts.     

The cost of diabetes and obesity in Australia

Aims: To assess and compare the direct healthcare and non-healthcare costs and government subsidies by body weight and diabetes status.

Methods: The Australian Diabetes, Obesity and Lifestyle study collected health service utilization and health-related expenditure data at the 2011–2012 follow-up surveys. Costing data were available for 4,409 participants. Unit costs for 2016–2017 were used where available or were otherwise inflated to 2016–2017 dollars. Age- and sex-adjusted costs per person were estimated using generalized linear models.

Results: The annual total direct cost ranged from $1,998 per person with normal weight to $2,501 per person with obesity in participants without diabetes. For those with diabetes, total direct costs were $2,353 per person with normal weight, $3,263 per person with overweight, and $3,131 per person with obesity. Additional expenditure as government subsidies ranged from $5,649 per person with normal weight and no diabetes to $8,085 per person with overweight and diabetes. In general, direct costs and government subsidies were higher for overweight and obesity compared to normal weight, regardless of diabetes status, but were more noticeable in the diabetes sub-group. The annual total excess cost compared with normal weight people without diabetes was 26% for obesity alone and 46% for those with obesity and diabetes.

Limitations: Participants included in this study represented a healthier cohort than the Australian population. The relatively small sample of people with both obesity and diabetes prevented a more detailed analysis by obesity class.

Conclusion: Overweight and obesity are associated with increased costs, which are further increased in individuals who also have diabetes. Interventions to prevent overweight and obesity or reduce weight in people who are overweight or obese, and prevent diabetes, should reduce the financial burden.