Second-Order Ambiguity in Very Low Probability Risks: Food Safety Valuation

Food consumption involves inherently risky decisions with uncertain probabilities. This study examines how second-order ambiguity, or uncertainty over probabilities, affects food safety decisions. We conduct a food safety survey wherein subjects face both unambiguous and ambiguous situations, each with the same expected value. Respondents show a preference for unambiguous situations and state a willingness to pay to avoid ambiguityambiguity, ambiguity avoidance, expected utility theory, food safety, low probability events, risk, second-order probabilities, uncertainty, Risk and Uncertainty,

EFFECT OF A 12-WEEK HOME-BASED NEUROMUSCULAR ELECTRICAL STIMULATION TREATMENT ON CLINICAL OUTCOMES FOLLOWING ARTICULAR CARTILAGE KNEE SURGERY

Articular cartilage defects in the knee are common, and can result in pain, decreased function and decreased quality of life. Untreated defects are considered to be a risk factor for developing osteoarthritis, a progressive degenerative joint disease with minimal treatment options. To address these issues, various surgical procedures are available to treat articular cartilage defects in the knee. While these procedures overall have positive results, after surgery patients experience large and persistent deficits in quadriceps strength. A contributing factor to this post-surgical weakness is believed to be the extended post-operative non-weight bearing period, with full weight bearing not initiated until approximately 4 – 6 weeks after surgery. During this non-weight bearing period a minimal amount of demand is placed upon the muscle. Subsequently, the quadriceps muscle undergoes a large degree of atrophy with a significant decrease in muscle strength. Muscular strength deficits reduce the knee joint stability, also increasing the risk of osteoarthritis development. Interventions that can be used to facilitate quadriceps strength while protecting the articular cartilage repair are needed. Neuromuscular electrical stimulation (NMES) is an effective post-knee surgery rehabilitation technique to regain quadriceps musculature. In recent years manufactures have been developing knee sleeve garments integrated with NMES allowing for portability of the NMES treatment. The primary aim of this study was to evaluate the effectiveness of a 12-week home-based neuromuscular electrical stimulation treatment on post-surgical clinical outcomes (quadriceps strength, lower extremity function, and patient reported outcomes) after articular cartilage knee surgery. Patients were randomized between a standard of care home-treatment group and a NMES home-treatment group. Patients completed isometric quadriceps strength testing, the Y-balance test, and the Knee Injury and Osteoarthritis Outcome Score (KOOS) before surgery and at 3-months after surgery. The secondary aims of this study were to determine the most effective NMES parameters for post-surgical quadriceps strength; and to develop a framework to identify factors that may influence a patient’s adherence to a prescribed therapy program. From our results we can make several conclusions. First, we found only a small number of studies utilize similar parameters for post-surgical quadriceps strength treatments. The majority of the parameters reported in the literature were highly variable between studies. Second, clinicians can utilize the expanded Health Belief Model to identify situational and personal factors unique to a patient that may impact adherence to a prescribed treatment. Clinicians can then implement the proposed interventional strategies to address the identified situational and personal factors. Finally, there was no difference in quadriceps strength, lower extremity function, or self-reported scores at 3-month between a home-based NMES treatment and a standard of care home-based treatment. Patients’ adherence to the treatment protocols may have been a major factor contributing to these results. Utilizing a model, such as the proposed expanded Health Belief Model, may assist clinicians in improving a patients’ adherence to future prescribed home-treatment programs

Unanimous Consensus Against AGM?

Given the role consensus is supposed to play in the social aspects of inquiry and deliberation, it is important that we may always identify a consensus as the basis of joint inquiry and deliberation. However, it turns out that if we think of an agent revising her beliefs to reach a consensus, then, on the received view of belief revision, AGM belief revision theory, certain simple and compelling consensus positions are not always available

Evaluating the Conditions for Robust Mechanism Design Abstract: We assess the strength of the different conditions identified in the literature of robust mechanism design. We focus on three conditions: ex post incentive compatibility, robust monotonicity, and robust measurability. Ex post incentive compatibility has been shown to be necessary for any concept of robust implementation, while robust monotonicity and robust measurability have been shown to be necessary for robust (full) exact and virtual implementation, respectively. This paper shows that while violations of ex post incentive compatibility and robust monotonicity do not easily go away, we identify a mild condition on environments in which robust measurability is satisfied by all social choice functions over an open and dense subset of first-order types. We conclude that there is a precise sense in which robust virtual implementation can be significantly more permissive than robust exact implementation.

robust mechanism design; ex post incentive compatibility; robust monotonicity; robust measurability

Rationally choosing beliefs: some open questions

Carlos Alchourrón, Peter Gärdenfors and David Makinson published in 1985 a seminal article on belief change in the Journal of Symbolic Logic (Alchourrón et al., 1985). Researchers from various disciplines, from computer science to mathematical economics to philosophical logic, have continued the work first presented in this seminal paper during the last two decades. This paper explores some salient foundational trends that interpret the act of changing view as a decision. We will argue that some of these foundational trends are already present, although only tacitly, in the original article by the AGM trio. Other accounts decidedly depart from the view of contraction and revision presented in this seminal paper. I shall survey various types of theories that progressively depart form the axiomatic treatment defended by AGM. First, I consider theories where rational agents are considered as maximizers as opposed to optimizers (in the sense of (Sen, 1997a)). Second, I consider which feasible set to use in contraction understood as a cognitive decision. This leads to rethink the very notion of what minimal change in contraction is. I shall conclude with some philosophical reflections concerning the sort of epistemological voluntarism that is tacit in seeing change in view as a rational choice.Carlos Alchourrón, Peter Gärdenfors y David Makinson publicaron en 1985 un artículo seminal sobre cambio de creencias en Journal of Symbolic Logic (Alchourrón et al., 1985). Investigadores de varias disciplinas, desde la ciencia de la computación hasta la economía matemática y la lógica filosófica, han continuado en las dos últimas décadas esta línea de investigación. Este trabajo explora algunos aspectos fundacionalmente salientes que interpretan el acto de cambio de vista como una decisión. Argumentaremos que algunos de esos aspectos fundacionales ya estaban presentes, aunque solo tácitamente, en el artículo original del trío AGM. Otros abordajes parten decididamente de la contracción y revisión tal como fueran presentadas en el trabajo seminal. Inspeccionaré varios tipos de teorías que progresivamente parten del tratamiento axiomático defendido por AGM. Primero, considero teorías donde los agentes racionales aparecen como maximizadres opuestos a los optimiadores (en el sentido de (Sen, 1997a)). Segundo, me pregunto cuál conjunto derrotable debe usarse en una contracción entendida como una decisión cognitiva, lo cual lleva a repensar la importante cuestión de en qué consiste la noción de cambio mínimo en la contracción. Concluiré con algunas reflexiones filosóficas acerca de la suerte de voluntarismo epistemológico que está tácito en la concepción del cambio como una opción racional

Monetary policy in the 2008-2009 recession

The recession that began with a cyclical peak in December 2007 originated in a combination of real shocks because of a fall in housing wealth and a fall in real income from an increase in energy prices. The most common explanation for the intensification of the recession that began in the late summer of 2008 is the propagation of these shocks through dysfunction in credit markets. The alternative explanation offered in this article emphasizes propagation through contractionary monetary policy. The first explanation stresses the importance of credit-market interventions (credit policy). The second emphasizes the importance of money creation (money-creation policy). According to Federal Open Market Committee (FOMC) Chairman William McChesney Martin, "The System should always be engaged in a ruthless examination of its past record" (FOMC Minutes, 11/26/68, 1,456).Monetary policy ; Credit