A critical overview of privacy-preserving approaches for collaborative forecasting

Cooperation between different data owners may lead to an improvement in forecast quality—for instance, by benefiting from spatiotemporal dependencies in geographically distributed time series. Due to business competitive factors and personal data protection concerns, however, said data owners might be unwilling to share their data. Interest in collaborative privacy-preserving forecasting is thus increasing. This paper analyzes the state-of-the-art and unveils several shortcomings of existing methods in guaranteeing data privacy when employing vector autoregressive models. The methods are divided into three groups: data transformation, secure multi-party computations, and decomposition methods. The analysis shows that state-of-the-art techniques have limitations in preserving data privacy, such as (i) the necessary trade-off between privacy and forecasting accuracy, empirically evaluated through simulations and real-world experiments based on solar data; and (ii) iterative model fitting processes, which reveal data after a number of iterations.     

Seemingly inconsistent analyst revisions

In about 20%–30% of cases where an analyst revises two outputs (namely, earnings estimates, target prices, or stock recommendations) simultaneously, the two estimates are revised in opposite directions. Existing literature notes that these inconsistent outputs are widespread, and concludes that they are lower-quality, driven by strategic bias, and are viewed as less valid by investors. We find that these characterizations are generally inaccurate. Apparent inconsistency is largely driven by accounting and economic factors, with only limited evidence that investment banking-related conflicts play a role. Moreover, inconsistent outputs are neither less accurate than consistent outputs nor do they resolve less investor uncertainty upon their release. Overall, our results suggest that researchers should be cautious in interpreting the correlation between analyst outputs as a measure of bias or quality, and in using a single analyst output as a proxy for an analyst's overall views.     

Least Squares Asymptotics in Spurious and Cointegrated Panel Regressions with Common and Idiosyncratic Stochastic Trends*

This article makes an analytical study of the effects of the presence of both common and idiosyncratic stochastic trends on the pooled least squares estimator. The results suggest that the usual result of asymptotic normality depends critically on the absence of the common stochastic trend.     

Sustainability marketing research: past,present and future

Abstract

This paper provides a synthesis and critical assessment of the sustainability marketing literature, from the period 1998–2013, building on a previous assessment from 1971 to 1998. It details research within major marketing journals and critically assesses this research in relation to the on-going conversation which focuses on marketing’s relationship with the natural environment. Differences in the content and depth of sustainability coverage in marketing journals are considered. Potential avenues for future sustainability marketing research are proposed, with a particular call for theoretical and managerial reflections which tackle broader systemic and institutional issues within the discipline.     

Geographic distribution of suicide and railway suicide in Belgium, 2008–2013: a principal component analysis

This study investigated the geographic distribution of suicide and railway suicide in Belgium over 2008--2013 on local (i.e., district or arrondissement) level. There were differences in the regional distribution of suicide and railway suicides in Belgium over the study period. Principal component analysis identified three groups of correlations among population variables and socio-economic indicators, such as population density, unemployment, and age group distribution, on two components that helped explaining the variance of railway suicide at a local (arrondissement) level. This information is of particular importance to prevent suicides in high-risk areas on the Belgian railway network.     

Regulation of relationships between heterogeneous farmers and an aquifer accounting for lag effects

Many environmental problems are due to damage caused by pollutants that accumulate with a time lag following their emission. In this study, we focus on nitrates used in agriculture, which can pollute groundwater many years after their initial application. A dynamic optimal control problem with heterogeneous farmers is proposed. The usual structural parameters such as the discount rate, the natural clearing rate and the lagged time interval between the occurrence of soil‐level pollution and the impact on groundwater are taken into account. We also examine pollution as caused by a continuous set of farms characterised by their individual performance index and by their individual marginal contribution to the pollution. The issue is further investigated by taking account of change in the information context, successively related to perfect information and to asymmetric information. As a result, when the delay between the spreading of N‐fertilizer and the impact on the aquifer increases, that is, the longer the lag, the steady‐state pollution stock and the steady‐state shadow price of the stock both increase. Moreover, we show that the optimal regulation may require a decreasing amount of fertilizer over time, even in the case of initial underpollution.     

Collective self-governance in a marine community: expedition cruise tourism at Svalbard

Collective self-governance is gaining attention in the literature for maintaining the quality of key attractions and promoting sustainable tourism. The long-term success of collective self-governance is dependent on both its internal organization and its embeddedness in external state and non-state regulations. This paper presents the marine community concept, consisting of a policy and a user community, as a framework for investigating the internal and external dynamics of collective self-governance and its ability to steer toward sustainable cruise tourism. As methodology, a case study design was chosen which was primarily studied by means of interviews with a spectrum of relevant actors concerning expedition cruise tourism at Svalbard. By applying the marine community to Svalbard expedition cruise tourism governance, we draw the following conclusions: (1) collective self-governance complements governmental regulation through access to knowledge, conflict resolution and rule-compliance based on disclosure, traceability and trust; (2) collective self-governance's increasing role in the policy community alienates the expedition crew from the user community; and (3) informational overflow by co-existence of collective self-governance and state-governance challenges sustainable cruise tourism. Collective self-governance would, therefore, benefit from reflection, especially regarding the role of the user community that functions as an intermediary between state and self-governance regulations.     

Reducing the distance: financial services education in web-extended learning environments

It is estimated that financial services comprise around 15% of the global economy. From the supply side, one key to meeting this demand is being able to educate and certify the people who provide these services. With the advent of the internet and related technologies, the ability to deliver financial services education synchronously to both online and on-campus attendees has become a viable alternative to pure face-to-face or pure online asynchronous education. Nonetheless, one question remains: can virtual technology deliver comparable quality of financial services educational experience as face-to-face teaching? It is this question our paper addresses using the theory of transactional distance. The theory of transactional distance postulates that for optimal learning, the cognitive gap between instructor(s) and learner(s) needs to be minimized. We explore how transactional distance in financial services education varies by attendance modality (in-class, online and mixed) in a synchronous, web-extended classroom. The implications for managers and researchers are explored.     

Modeling farmers’ decisions on tea varieties in Vietnam: a multinomial logit analysis

This article analyzes households’ choice on tea varieties in Vietnam by using a multinomial logit model. The modeling takes into account the issue of unobserved individual heterogeneity and the endogeneity of some explanatory variables (use of chemical and organic fertilizers). The results show that important factors influencing the decision to adopt one type of tea varieties include income, age, household size, farming contract, and use of organic fertilizers, but also membership of professional associations such as the Tea Association and the Farmers Union.