Local predictive influence in bayesian linear models with conjugate priors

Cook (1986) presented the idea of local influence to study the sensitivity of inferences to model assumptions:introduce a vector δ of perturbations to the model; choose a discrepancy function D to measure differences between the original inference and the inference under the perturbed model; study the behavior of D near δ = 0, the original model, usually by taking derivatives. Johnson and Geisser (1983) measure influence in Bayesian inference by the Kullback-Leibler divergence between predictive distributions. I~IcCulloch (1989) is a synthesis of Cook and Johnson and Geisser, using Kullback-Leibler divergence between posterior or predictive distributions as the discrepancy function in Bayesian local influence analyses. We analyze a special case for which McCulloch gives the general theory; namely, the linear model with conjugate prior. We present specific formulae for local influence measures for 1) changes in the parameters of the gamma prior for the precision, 2) changes in the mean of the normal prior for the regression coefficients, 3) changes in the covariance matrix of the normal prior for the regression coefficients and 4) changes in the case weights. Our method is an easy way to find locally influential subsets of points without knowing in advance the sizes of the subsets. The techniques are illustrated with a regression example.     

Changes in Aleut Concerns Following the Stakeholder-Driven Amchitka Independent Science Assessment

There is widespread agreement that stakeholders should be included in the problem‐formulation phase of addressing environment problems and, more recently, there have been attempts to include stakeholders in other phases of environmental research. However, there are few studies that evaluate the effects of including stakeholders in all phases of research aimed at solving environmental problems. Three underground nuclear blasts were detonated on Amchitka Island from 1965 to 1971. Considerable controversy developed when the Department of Energy (DOE) decided to “close” Amchitka. Concerns were voiced by subsistence Aleuts living in the region, resource trustees, and the State of Alaska, among others. This article evaluates perceptions of residents of three Aleutian village before (2003) and after (2005) the Consortium for Risk Evaluation with Stakeholder Participation's (CRESP) Amchitka Independent Science Assessment (AISA). The CRESP AISA provided technical information on radionuclide levels in biota to inform questions of seafood safety and food chain health. CRESP used the questions asked at public meetings in the Aleut communities of Atka, Nikolski, and Unalaska to evaluate attitudes and perceptions before and after the AISA. Major concerns before the AISA were credibility/trust of CRESP and the DOE, and information about biological methodology of the study. Following the AISA, people were most concerned about health effects and risk reduction, and trust issues with CRESP declined while those for the DOE remained stable. People’s relative concerns about radionuclides declined, while their concerns about mercury (not addressed in the AISA) increased, and interest in ecological issues (population changes of local species) and the future (continued biomonitoring) increased from 2003 to 2005. These results suggest that questions posed at public meetings can be used to evaluate changes in attitudes and perceptions following environmental research, and the results are consistent with the hypothesis that the AISA answered questions about radionuclides, and lowered overall concern about radionuclides, but left unanswered concerns about the health effects of mercury.     

Risk-Reducing Legal Documents: Controlling Personal Health and Financial Resources

Every adult can eliminate the risk of losing control of personal health decisions and financial resources by having a last will and testament, health proxy, power of attorney, and living trust. Yet evidence suggests that less than a majority of adult Americans have these documents. We surveyed 900 adult Americans (25 plus years old) to determine what factors predict the possession of these risk-reducing documents. In total, 46% had a living will and testament, 32% a durable power of attorney, 30% a health proxy, and 18% a living trust. Events that prompt people with wealth to secure these documents, such as increasing age, getting married, having children, and experiencing a life-threatening event were the strongest predictors of having a will. These were also among the strongest predictors of having a health proxy, along with a personal history of being proactive, and a family history that fostered trust of attorneys. Affluence, age, and education were the strongest predictors of having a living trust, and the strongest correlate of having a durable power of attorney was having faced a life-threatening event, positive experiences with attorneys, and higher educational achievement.     

F?rdern aktienkursbasierte Vergütungsinstrumente langfristig orientierte Unternehmensentscheidungen? Lehren aus der Kreditkrise

The question whether stock-based management incentives encourage long-term oriented management decisions is the topic of a controversial public debate. Also, the existing academic literature provides no clear picture, mainly due to endogeneity problems. In this paper, we reexamine the issue in the context of the recent credit crises, which allows us to solve the endogeneity problem. In the empirical analysis we find that firms, which have awarded stock-based incentives to their executives prior or during the financial crises, face substantially lower cuts in investment spending. These firms also show higher levels of R&D investments during the financial crises. Overall, our results suggest that stock based long-term incentives promote long-term oriented management decisions.     

The behavioural wedge

When nations fail to agree, can individual citizens make a difference? The third of our post-Copenhagen features is by Jonathan Gilligan, Thomas Dietz, Gerald T. Gardner, Paul C. Stern , and Michael P. Vandenbergh . They look at the effects that voluntary actions by individuals can have, and at the policies that can best encourage such actions.     

Home prices and the 2008 presidential election: Evidence from state level data

The purpose of this paper is to examine the role of housing prices in the outcome of the 2008 U.S. presidential election. Based on data for the 50 states, this study postulates a multivariate model in which the impact of home values is exposed while controlling for other explanatory factors might have exerted independent effects on the Democratic victory. Results of estimation indicate a significant inverse effect of property price appreciation on Democratic votes.     

Knowledge and Identity: A Review

This paper reviews the literature in a number of areas that converge upon the theme of the role of knowledge within professional identity. Within knowledge transfer literature the individual perspective is underdeveloped, and this paper seeks to contribute by exploring the function of knowledge within an individual's professional identity, thus unfolding a theoretical connection between the literatures of knowledge and identity. Its central argument concurs with Szulanski's notion of ‘internal stickiness’ as a barrier to knowledge transfer but extends this hypothesis into the psychological ownership of knowledge and to the idea of ‘possessiveness’. The paper argues that the value of self‐categorized knowledge places the latter within the individual's cognitive structure of their identity. It offers up the idea of valued knowledge to the knowledge transfer domain and suggests that feelings of possessiveness towards knowledge may intervene in the willingness of an individual to disclose knowledge in a knowledge transfer process.