Fictive Learning in Choice under Uncertainty: A Logistic Regression Model

This paper is an exposition of an experiment on revealed preferences, where we posite a novel discrete binary choice model. To estimate this model, we use general estimating equations or GEE. This is a methodology originating in biostatistics for estimating regression models with correlated data. In this paper, we focus on the motivation for our approach, the logic and intuition underlying our analysis and a summary of our findings. The missing technical details are in the working paper by Bunn, et al. (2013). The experimental data is available from the corresponding author: [email protected] . The recruiting poster and informed consent form are attached as appendices

Testing for Fictive Learning in Decision-Making under Uncertainty

We conduct two experiments where subjects make a sequence of binary choices between risky and ambiguous binary lotteries. Risky lotteries are defined as lotteries where the relative frequencies of outcomes are known. Ambiguous lotteries are lotteries where the relative frequencies of outcomes are not known or may not exist. The trials in each experiment are divided into three phases: pre-treatment, treatment and post-treatment. The trials in the pre-treatment and post-treatment phases are the same. As such, the trials before and after the treatment phase are dependent, clustered matched-pairs, that we analyze with the alternating logistic regression (ALR) package in SAS. In both experiments, we reveal to each subject the outcomes of her actual and counterfactual choices in the treatment phase. The treatments differ in the complexity of the random process used to generate the relative frequencies of the payoffs of the ambiguous lotteries. In the first experiment, the probabilities can be inferred from the converging sample averages of the observed actual and counterfactual outcomes of the ambiguous lotteries. In the second experiment the sample averages do not converge. If we define fictive learning in an experiment as statistically significant changes in the responses of subjects before and after the treatment phase of an experiment, then we expect fictive learning in the first experiment, but no fictive learning in the second experiment. The surprising finding in this paper is the presence of fictive learning in the second experiment. We attribute this counterintuitive result to apophenia: “seeing meaningful patterns in meaningless or random data.” A refinement of this result is the inference from a subsequent Chi-squared test, that the effects of fictive learning in the first experiment are significantly different from the effects of fictive learning in the second experiment

Nonsupersymmetric brane vacua in stabilized compactifications

We derive the equations for the nonsupersymmetric vacua of D3-branes in the presence of nonperturbative moduli stabilization in type IIB flux compactifications, and solve and analyze them in the case of two particular 7-brane embeddings at the bottom of the warped deformed conifold. In the limit of large volume and long throat, we obtain vacua by imposing a constraint on the 7-brane embedding. These vacua fill out continuous spaces of higher dimension than the corresponding supersymmetric vacua, and have negative effective cosmological constant. Perturbative stability of these vacua is possible but not generic. Finally, we argue that anti-D3-branes at the tip of the conifold share the same vacua as D3-branes.Comment: 17 pages, 1 figure, LaTeX. v2: references added, typo fixed. v3: version appearing in JHE

Rind from purple mangosteen (Garcinia mangostana) attenuates diet-induced physiological and metabolic changes in obese rats

The pulp of the purple mangosteen, Garcinia mangostana, is a popular tropical fruit but the rind containing xanthones such as α-mangostin together with procyanidins and anthocyanidins is usually discarded as waste. However, this rind has been used in South-East Asia for diarrhoea, dysentery, skin infections and wounds. As xanthones have reported anti-inflammatory and antioxidant responses, this study has determined the bioactive compounds and evaluated the effects of G. mangostana rind on physiological, metabolic, liver and cardiovascular parameters in rats with diet-induced metabolic syndrome. Rats fed a diet with increased simple sugars and saturated fats developed obesity, hypertension, increased left ventricular stiffness, dyslipidaemia and fatty liver. Administration of G. mangostana rind as 5% of the food to rats with diet-induced metabolic syndrome gave a dose of 168 mg/kg/day α-mangostin, 355 mg/kg/day procyanidins, 3.9 mg/kg/day anthocyanins and 11.8 mg/kg/day hydroxycitric acid for 8 weeks which reduced body weight and attenuated physiological and metabolic changes in rats including decreased abdominal fat deposition, decreased abdominal circumference and whole-body fat mass, improved liver structure and function and improved cardiovascular parameters such as systolic blood pressure, left ventricular stiffness and endothelial function. These responses were associated with decreased infiltration of inflammatory cells, decreased deposition of collagen in both heart and liver and decreased mean adipocyte size in retroperitoneal adipose tissues. We conclude that, in rats with diet-induced metabolic syndrome, chronic intake of G. mangostana rind decreased infiltration of inflammatory cells which decreased physiological, metabolic, liver and cardiovascular symptoms

L1-determined ideals in group algebras of exponential Lie groups

A locally compact group $G$ is said to be $\ast$-regular if the natural map \Psi:\Prim C^\ast(G)\to\Prim_{\ast} L^1(G) is a homeomorphism with respect to the Jacobson topologies on the primitive ideal spaces \Prim C^\ast(G) and \Prim_{\ast} L^1(G). In 1980 J. Boidol characterized the $\ast$-regular ones among all exponential Lie groups by a purely algebraic condition. In this article we introduce the notion of $L^1$-determined ideals in order to discuss the weaker property of primitive $\ast$-regularity. We give two sufficient criteria for closed ideals $I$ of $C^\ast(G)$ to be $L^1$-determined. Herefrom we deduce a strategy to prove that a given exponential Lie group is primitive $\ast$-regular. The author proved in his thesis that all exponential Lie groups of dimension $\le 7$ have this property. So far no counter-example is known. Here we discuss the example $G=B_5$, the only critical one in dimension $\le 5$

Anthocyanins in chronic diseases : the power of purple

Anthocyanins are mainly purple-coloured phenolic compounds of plant origin that as secondary metabolites are important in plant survival. Understanding their health benefits in humans requires sourcing these unstable compounds in sufficient quantities at a reasonable cost, which has led to improved methods of extraction. Dark-coloured fruits, cereals and vegetables are current sources of these compounds. The range of potential sustainable sources is much larger and includes non-commercialised native plants from around the world and agri-waste containing anthocyanins. In the last 5 years, there have been significant advances in developing the therapeutic potential of anthocyanins in chronic human diseases. Anthocyanins exert their beneficial effects through improvements in gut microbiota, oxidative stress and inflammation, and modulation of neuropeptides such as insulin-like growth factor-1. Their health benefits in humans include reduced cognitive decline; protection of organs such as the liver, as well as the cardiovascular system, gastrointestinal tract and kidneys; improvements in bone health and obesity; and regulation of glucose and lipid metabolism. This review summarises some of the sources of anthocyanins and their mechanisms and benefits in the treatment of chronic human diseases

The asymptotic dynamics of three-dimensional Einstein gravity with a negative cosmological constant

Liouville theory is shown to describe the asymptotic dynamics of three-dimensional Einstein gravity with a negative cosmological constant. This is because (i) Chern-Simons theory with a gauge group $SL(2,R) \times SL(2,R)$ on a space-time with a cylindrical boundary is equivalent to the non-chiral $SL(2,R)$ WZW model; and (ii) the anti-de Sitter boundary conditions implement the constraints that reduce the WZW model to the Liouville theory.Comment: 10 pages in LaTeX, LaTeX problem fixe

Toward quantification of the feasible potential of land-based carbon dioxide removal

Global climate-change overshoot scenarios, where warming exceeds Paris Agreement limits before being brought back down, are highly dependent on land-based carbon dioxide removal (CDR). In the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6), such scenarios are supported by optimistic global assessments of the technical and economic potential for land-based CDR. However, a further type of potential—the ‘‘feasible’’ potential, which includes socio-cultural, environmental, and institutional factors—is noted in the AR6 but not quantified. Here, we set out research frameworks to work toward quantification of this feasible potential. We first argue that quantifying the feasible potential will substantiallyreduce current assessed CDR potential. Second, we demonstrate how transdisciplinary methods are improving understanding of feasibility constraints on land-based CDR. Third, we explore frameworks for synthesizing these advances during the next IPCC assessment process. We conclude that the research community should carefully consider the use of techno-economic CDR assessments in evidence for policymaker

Intraoperative electrocochleographic characteristics of auditory neuropathy spectrum disorder in cochlear implant subjects

Auditory neuropathy spectrum disorder (ANSD) is characterized by an apparent discrepancy between measures of cochlear and neural function based on auditory brainstem response (ABR) testing. Clinical indicators of ANSD are a present cochlear microphonic (CM) with small or absent wave V. Many identified ANSD patients have speech impairment severe enough that cochlear implantation (CI) is indicated. To better understand the cochleae identified with ANSD that lead to a CI, we performed intraoperative round window electrocochleography (ECochG) to tone bursts in children (n = 167) and adults (n = 163). Magnitudes of the responses to tones of different frequencies were summed to measure the “total response” (ECochG-TR), a metric often dominated by hair cell activity, and auditory nerve activity was estimated visually from the compound action potential (CAP) and auditory nerve neurophonic (ANN) as a ranked “Nerve Score”. Subjects identified as ANSD (45 ears in children, 3 in adults) had higher values of ECochG-TR than adult and pediatric subjects also receiving CIs not identified as ANSD. However, nerve scores of the ANSD group were similar to the other cohorts, although dominated by the ANN to low frequencies more than in the non-ANSD groups. To high frequencies, the common morphology of ANSD cases was a large CM and summating potential, and small or absent CAP. Common morphologies in other groups were either only a CM, or a combination of CM and CAP. These results indicate that responses to high frequencies, derived primarily from hair cells, are the main source of the CM used to evaluate ANSD in the clinical setting. However, the clinical tests do not capture the wide range of neural activity seen to low frequency sounds

Generation and Evolution of Spin Entanglement in NRQED

A complete analysis on the generation of spin entanglement from NRQED is presented. The results of entanglement are obtained with relativistic correction to the leading order of (v/c)^2. It is shown that to this order the degree of entanglement of a singlet state does not change under time evolution whereas the triplet state can change.Comment: 8 pages, 1 figure, to appear in Phys. Rev.