Barnes Hospital Record

https://digitalcommons.wustl.edu/bjc_barnes_record/1053/thumbnail.jp

A Note on Bayesian Model Selection for Discrete Data Using Proper Scoring Rules

We consider the problem of choosing between parametric models for a discrete observable, taking a Bayesian approach in which the within-model prior distributions are allowed to be improper. In order to avoid the ambiguity in the marginal likelihood function in such a case, we apply a homogeneous scoring rule. For the particular case of distinguishing between Poisson and Negative Binomial models, we conduct simulations that indicate that, applied prequentially, the method will consistently select the true model.Comment: 8 pages, 2 figure

A MODEL OF PESTICIDE RESISTANCE AS A COMMON PROPERTY AND EXHAUSTIBLE RESOURCE

A dynamic farm production model analyzes the interaction between the externalities caused by pest mobility and the development of pesticide resistance, a nonrenewable resource, in the context of agricultural biotechnologies. The model measures the effect of farmers' myopic behavior and the impact of pest mobility on the path of resistance.biotechnology, common property resource, European Corn Borer, externalities, pesticide resistance, intertemporal optimization, Research and Development/Tech Change/Emerging Technologies,

OPTIMAL PESTICIDE USAGE WITH RESISTANCE AND ENDOGENOUS TECHNOLOGICAL CHANGE

This paper develops a model analyzing the first best policy for a social planner when pesticide use causes resistance, the level of pest infestation is heterogeneous among farmers, and the development of a backstop technology is an endogenous and uncertain process which depends on the cumulative amount of R&D effort.Crop Production/Industries,

MANAGING PEST RESISTANCE: THE POTENTIAL OF CROP ROTATIONS AND SHREDDING

The current debate over resistance management plans mandated by the Environmental Protection Agency for transgenic crops ignores management practices that are complementary to refuge schemes. A dynamic production model is developed that measures the costs and benefits of crop rotation and shredding in terms of delaying resistance to Bt corn.biotechnology, common property resource, crop rotation, European Corn Borer, externalities, insecticide resistance, integrated pest management, intertemporal optimization, Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

Isospin-breaking interactions studied through mirror energy differences

Background: Information on charge-dependent (i.e., isospin-non-conserving) interactions is extracted from excited states of mirror nuclei. Purpose: Specifically, the purpose of the study is to extract effective isovector (Vpp 12Vnn) interactions which, in general, can either be of Coulomb or nuclear origin. Methods: A comprehensive shell-model description of isospin-breaking effects is used to fit data on mirror energy differences in the A = 42\u201354 region. The angular-momentum dependence of isospin-breaking interactions was determined from a systematic study of mirror energy differences. Results: The results reveal a significant isovector term, with a very strong spin dependence, beyond that expected of a two-body Coulomb interaction. Conclusions: The isospin-breaking terms that are extracted have a J dependence that is not consistent with the known CSB properties of the bare nucleon-nucleon interaction