Bayesian analysis of the linear reaction norm model with unknown covariate

The reaction norm model is becoming a popular approach for the analysis of G x E interactions. In a classical reaction norm model, the expression of a genotype in different environments is described as a linear function (a reaction norm) of an environmental gradient or value. A common environmental value is defined as the mean performance of all genotypes in the environment, which is typically unknown. One approximation is to estimate the mean phenotypic performance in each environment, and then treat these estimates as known covariates in the model. However, a more satisfactory alternative is to infer environmental values simultaneously with the other parameters of the model. This study describes a method and its Bayesian MCMC implementation that makes this possible. Frequentist properties of the proposed method are tested in a simulation study. Estimates of parameters of interest agree well with the true values. Further, inferences about genetic parameters from the proposed method are similar to those derived from a reaction norm model using true environmental values. On the other hand, using phenotypic means as proxies for environmental values results in poor inferences

Social enterprise and disruption innovation: evaluating the role of Rumie's free educational software in seven developing economies

This paper reviews the provision of free educational hardware and software provided by one social enterprise to under resourced children in seven countries. The social and economic challenges faced by this social enterprise are highlighted; the implications for social enterprise of adopting disruptive innovation and of blended learning techniques in an educational context; and the importance of evaluating projects in terms of research methods. Three research questions were posed: what is the educational benefit of using Rumie? [Value dimension]; what criteria can be used to evaluate the use of Rumie in the field? [The capability dimension]; what feedback is there from students, teachers, etc. [The collaboration dimension]. Quantitative usage data and qualitative feedback were collected. Findings show that the tablets help improve pupils math and reading abilities and the educal entertainment does not appear to be at the expense of learning about more traditional subjects. Feedback from teachers and pupils appears to be extremely positive. More specific lessons learned about research methods in evaluating social entrepreneurship projects in developing economies are identified; and implications for adapting the theory of disruptive innovation

Epistemic Schmagency?

Constructivist approaches in epistemology and ethics offer a promising account of normativity. But constructivism faces a powerful Schmagency Objection, raised by David Enoch. While Enoch’s objection has been widely discussed in the context of practical norms, no one has yet explored how the Schmagency Objection might undermine epistemic constructivism. In this paper, I rectify that gap. First, I develop the objection against a prominent form of epistemic constructivism, Belief Constitutivism. Belief Constitutivism is susceptible to a Schmagency Objection, I argue, because it locates the source of normativity in the belief rather than the agent. In the final section, I propose a version of epistemic constructivism that locates epistemic normativity as constitutive of agency. I argue that this version has the resources to respond to the Schmagency Objection

The impact of trust on private equity contracts

This paper adresses the impact of trust on private equity contracts. Trust between investor and entrepreneur is essential to help overcome control problems, especially in an environment with severe agency risks and incomplete contracts. In this study, information about the effects of trust is collected using a simulation with 144 entrepreneurs and investors. We find that trust has an impact on the desired contracts of entrepreneurs, but not on that of investors. Our findings suggest that for parties, faced with potentially large agency problems (investors), trust and control seem to play complementary roles. On the other hand, for parties faced with smaller agency problems (entrepreneurs), trust seems to be a substitute for control

Levels of Intestinal Inflammation and Fibrosis in Resection Specimens after Preoperative Anti-Tumor Necrosis Factor Alpha Treatment in Patients with Crohn's Disease:A Comparative Pilot Study

Background. Strictures are a common complication in Crohn’s disease (CD), found in more than 50% of patients. They are characterized by the excessive deposition of extracellular proteins in the tissue as a result of the chronic inflammatory process. The effect of anti-tumor necrosis factor alpha (TNF-α) therapy on the development of fibrosis is not yet fully understood. Aim. To investigate whether the degree of intestinal inflammation and fibrosis is correlated with preoperative anti-TNF-α therapy in patients with CD who are undergoing bowel resection. Methods. This unblinded, prospective, single tertiary center, pilot cohort study included all adult patients with CD who underwent elective, laparoscopic, or open intestinal resection. Preoperative investigations included measurement of blood TNF-α concentration, specific antidrug antibodies, and the concentration of selected inflammatory cytokines. Three pathologists independently examined the specimens and assessed the degree of inflammation and fibrosis. Results. Histopathological specimens from 10 patients with CD who underwent ileocecal or ileocolic resections were retrieved. Four of those patients were on anti-TNF-α treatment prior to surgery. The last dose of the anti-TNF-α agent was administered 1–9 weeks prior to bowel resection. Patients on anti-TNF-α treatment had a higher fibrosis score than controls (p=0.01). Anti-TNF-α treatment was not associated with an increase in CD68- or CD163-positive macrophages. There was no significant relationship between the time from the final preoperative anti-TNF-α dose to surgery and the fibrosis score. No significant association was found between the concentration of major inflammatory cytokines, including TNF-α, and the fibrosis score or degree of inflammation. Conclusions. Patients who underwent preoperative anti-TNF-α treatment had a higher fibrosis score than controls