Policy Reversals in Risk Management: The Effect of Refined Analyses

Reversals of policy recommendations occur in risk management when the social decision maker aggregates individuals' subjective utilities for the outcomes of a risky policy measure. The level of detail with which these outcomes are described can significantly affect the resulting policy recommendation. The choice of the level of detail on which we conduct an analysis therefore amounts to an implicit value judgment. Moreover, the power to fix the level of the analysis implies partial control over policy recommendations. We propose an alternative approach to decision—theoretically sound risk management

Fair Kidney Allocation Based on Waiting Time

We study the allocation of cadaveric donor kidneys for transplantation based merely on waiting time. Despite the first impression, this simple allocation rule turns out to possess very attractive ethical and medical properties. Current allocation rules do not consider criteria such as sex, age and race perhaps for fear of morally unacceptable allocations, although certain combinations of these criteria are known to affect graft survival rates. We demonstrate that allocation by waiting time automatically protects disadvantaged patient types and puts them in a near to optimal position. The inclusion of sex, age and race will therefore not lead to morally unacceptable allocations. This allows individual patients to improve the expected survival time of their graft relative to the status quo without being penalized by the allocation rule. Moreover, decisions about when to start compromising on expected graft survival rates in favour of shorter waiting times are made locally by patients and their medical advisers rather than by a centralized protocol

TECHNICAL REPORT: The Instability of Ex Post and Robust Aggregation without State-Consequence Separation

We prove the results of Hild (2001a, 2001b) in a framework that does not presuppose the separation of states and consequences. We introduce additional assumptions to make up for the structure that is lost by abandoning the representation of acts as functions from states to consequences

Roemer on Equality of Opportunity

We critically discuss John Roemer’s normative criterion of equal opportunity and advance opportunity dominance as an alternative criterion for the evaluation of policies. For Roemer, strict equality of opportunity obtains when people, irrespectively of circumstances beyond their control, have the same ability to achieve advantage through their free choices. To implement this idea, Roemer sorts people with similar circumstances into types and takes their free choices to be represented by their behaviour relative to other members of the same type or, as Roemer calls it, by their ‘relative effort’. He then proposes that society should maximize the average advantage of all those whose circumstances cause them to be least well–off relative to others who have expended the same degree of relative effort. We argue that typing and the relative effort metric conflate the factors for which we do and do not want to hold individuals responsible, whenever these factors are statistically correlated. Moreover, Roemer’s rule for policy selection burdens the concept of equal opportunity with foreign distributive principles. Pointing to an inconsistency in Roemer’s argument, we also note that his selection rule violates his own requirement of Pareto-optimality. In response to these difficulties, we advance the criterion of opportunity dominance which is Pareto optimal, maintains conceptual purity and does not conflate the factors for which individuals should and should not be held responsible. This criterion determines a set of candidate policies that are undominated in opportunity and from which a final policy must be selected by additional, conceptually distinct principles of distributive justice

Upgrade of the ultracold neutron source at the pulsed reactor TRIGA Mainz

The performance of the upgraded solid deuterium ultracold neutron source at the pulsed reactor TRIGA Mainz is described. The current configuration stage comprises the installation of a He liquefier to run UCN experiments over long-term periods, the use of stainless steel neutron guides with improved transmission as well as sputter-coated non-magnetic $^{58}$NiMo alloy at the inside walls of the thermal bridge and the converter cup. The UCN yield was measured in a `standard' UCN storage bottle (stainless steel) with a volume of 32 litres outside the biological shield at the experimental area yielding UCN densities of 8.5 /cm$^3$; an increase by a factor of 3.5 compared to the former setup. The measured UCN storage curve is in good agreement with the predictions from a Monte Carlo simulation developed to model the source. The growth and formation of the solid deuterium converter during freeze-out are affected by the ortho/para ratio of the H$_2$ premoderator.Comment: 12 pages, 7 figure

A Late Role for bmp2b in the Morphogenesis of Semicircular Canal Ducts in the Zebrafish Inner Ear

BACKGROUND:The Bone Morphogenetic Protein (BMP) genes bmp2 and bmp4 are expressed in highly conserved patterns in the developing vertebrate inner ear. It has, however, proved difficult to elucidate the function of BMPs during ear development as mutations in these genes cause early embryonic lethality. Previous studies using conditional approaches in mouse and chicken have shown that Bmp4 has a role in semicircular canal and crista development, but there is currently no direct evidence for the role of Bmp2 in the developing inner ear. METHODOLOGY/PRINCIPAL FINDINGS:We have used an RNA rescue strategy to test the role of bmp2b in the zebrafish inner ear directly. Injection of bmp2b or smad5 mRNA into homozygous mutant swirl (bmp2b(-/-)) embryos rescues the early patterning defects in these mutants and the fish survive to adulthood. As injected RNA will only last, at most, for the first few days of embryogenesis, all later development occurs in the absence of bmp2b function. Although rescued swirl adult fish are viable, they have balance defects suggestive of vestibular dysfunction. Analysis of the inner ears of these fish reveals a total absence of semicircular canal ducts, structures involved in the detection of angular motion. All other regions of the ear, including the ampullae and cristae, are present and appear normal. Early stages of otic development in rescued swirl embryos are also normal. CONCLUSIONS/SIGNIFICANCE:Our findings demonstrate a critical late role for bmp2b in the morphogenesis of semicircular canals in the zebrafish inner ear. This is the first demonstration of a developmental role for any gene during post-embryonic stages of otic morphogenesis in the zebrafish. Despite differences in the early stages of semicircular canal formation between zebrafish and amniotes, the role of Bmp2 in semicircular canal duct outgrowth is likely to be conserved between different vertebrate species

Economic Analysis of Knowledge: The History of Thought and the Central Themes

Following the development of knowledge economies, there has been a rapid expansion of economic analysis of knowledge, both in the context of technological knowledge in particular and the decision theory in general. This paper surveys this literature by identifying the main themes and contributions and outlines the future prospects of the discipline. The wide scope of knowledge related questions in terms of applicability and alternative approaches has led to the fragmentation of research. Nevertheless, one can identify a continuing tradition which analyses various aspects of the generation, dissemination and use of knowledge in the economy