When ambiguity-averse investors process news of uncertain quality, they act as if they take a worst-case assessment of quality. As a result, they react more strongly to bad news than to good news. ...They also dislike assets for which information quality is poor, especially when the underlying fundamentals are volatile. These effects induce ambiguity premia that depend on idiosyncratic risk in fundamentals as well as skewness in returns. Moreover, shocks to information quality can have persistent negative effects on prices even if fundamentals do not change.
Though risk aversion and the elasticity of intertemporal substitution have been the subjects of careful scrutiny, the long-run risks literature as well as the broader literature using recursive ...utility to address asset pricing puzzles has ignored the full implications of their parameter specifications. Recursive utility implies that the temporal resolution of risk matters and a quantitative assessment thereof should be part of the calibration process. This paper gives a sense of the magnitudes of implied timing premia. Its objective is to inject temporal resolution of risk into the discussion of the quantitative properties of long-run risks and related models.
When faced with the chance to help someone in mortal danger, what is our first response? Do we leap into action, only later considering the risks to ourselves? Or must instinctive self-preservation ...be overcome by will-power in order to act? We investigate this question by examining the testimony of Carnegie Hero Medal Recipients (CHMRs), extreme altruists who risked their lives to save others. We collected published interviews with CHMRs where they described their decisions to help. We then had participants rate the intuitiveness versus deliberativeness of the decision-making process described in each CHMR statement. The statements were judged to be overwhelmingly dominated by intuition; to be significantly more intuitive than a set of control statements describing deliberative decision-making; and to not differ significantly from a set of intuitive control statements. This remained true when restricting to scenarios in which the CHMRs had sufficient time to reflect before acting if they had so chosen. Text-analysis software found similar results. These findings suggest that high-stakes extreme altruism may be largely motivated by automatic, intuitive processes.
In 1991, the AIDS Task Force of the American Academy of Neurology published nomenclature and research case definitions to guide the diagnosis of neurologic manifestations of HIV-1 infection. Now, 16 ...years later, the National Institute of Mental Health and the National Institute of Neurological Diseases and Stroke have charged a working group to critically review the adequacy and utility of these definitional criteria and to identify aspects that require updating. This report represents a majority view, and unanimity was not reached on all points. It reviews our collective experience with HIV-associated neurocognitive disorders (HAND), particularly since the advent of highly active antiretroviral treatment, and their definitional criteria; discusses the impact of comorbidities; and suggests inclusion of the term asymptomatic neurocognitive impairment to categorize individuals with subclinical impairment. An algorithm is proposed to assist in standardized diagnostic classification of HAND.
Ambiguity and Asset Markets Epstein, Larry G; Schneider, Martin
Annual review of financial economics,
01/2010, Volume:
2, Issue:
1
Journal Article
Peer reviewed
Open access
The Ellsberg paradox suggests that people's behavior is different in risky situations-when they are given objective probabilities-from their behavior in ambiguous situations-when they are not told ...the odds (as is typical in financial markets). Such behavior is inconsistent with subjective expected utility (SEU) theory, the standard model of choice under uncertainty in financial economics. This article reviews models of ambiguity aversion. It shows that such models-in particular, the multiple-priors model of Gilboa and Schmeidler-have implications for portfolio choice and asset pricing that are very different from those of SEU and that help to explain otherwise puzzling features of the data.
Objective
Whether febrile status epilepticus (FSE) produces hippocampal sclerosis (HS) and temporal lobe epilepsy (TLE) has long been debated. Our objective is to determine whether FSE produces acute ...hippocampal injury that evolves to HS.
Methods
FEBSTAT and 2 affiliated studies prospectively recruited 226 children aged 1 month to 6 years with FSE and controls with simple febrile seizures. All had acute magnetic resonance imaging (MRI), and follow‐up MRI was obtained approximately 1 year later in the majority. Visual interpretation by 2 neuroradiologists informed only of subject age was augmented by hippocampal volumetrics, analysis of the intrahippocampal distribution of T2 signal, and apparent diffusion coefficients.
Results
Hippocampal T2 hyperintensity, maximum in Sommer's sector, occurred acutely after FSE in 22 of 226 children in association with increased volume. Follow‐up MRI obtained on 14 of the 22 with acute T2 hyperintensity showed HS in 10 and reduced hippocampal volume in 12. In contrast, follow‐up of 116 children without acute hyperintensity showed abnormal T2 signal in only 1 (following another episode of FSE). Furthermore, compared to controls with simple febrile seizures, FSE subjects with normal acute MRI had abnormally low right to left hippocampal volume ratios, smaller hippocampi initially, and reduced hippocampal growth.
Interpretation
Hippocampal T2 hyperintensity after FSE represents acute injury often evolving to a radiological appearance of HS after 1 year. Furthermore, impaired growth of normal‐appearing hippocampi after FSE suggests subtle injury even in the absence of T2 hyperintensity. Longer follow‐up is needed to determine the relationship of these findings to TLE. ANN NEUROL 2014;75:178–185
Fetal anomaly diagnosis and termination of pregnancy Graf, William D.; Cohen, Bruce H.; Kalsner, Louisa ...
Developmental medicine and child neurology,
July 2023, 2023-Jul, 2023-07-00, 20230701, Volume:
65, Issue:
7
Journal Article
Peer reviewed
The aim of this review was to discuss bioethics in prenatal diagnosis and health care after recent legislative and judicial changes affecting reproductive rights, such as the repeal of ‘Roe v. Wade’ ...in the United States. We recognize that abortion involves particular moralities that are not universal or shared by all cultures, groups, and individuals. We reviewed the historical aspects of embryology and personhood, fetal morbidity and mortality, and parental options for prenatal diagnostic testing. We examined relevant ethical issues including informed consent, the emergence of fetal pain, reproductive autonomy, the fiduciary responsibilities of pregnant mothers, and the obligations of physicians caring for the maternal–fetal dyad. The code of medical ethics includes respect for decisional privacy and the protection of information shared in confidence. When a fetal anomaly is diagnosed, pregnant mothers must be informed about the risks, burdens, and alternatives in either continuing or terminating the pregnancy. Parental choice should include the right to refuse testing, the informed choice not to know about certain genetic test results, and the right to make informed decisions about the best interests of the future child. In the diagnosis and care of fetal anomalies, moral dilemmas arise. Before fetal viability, the mother's autonomy, sense of beneficence, and personal values should be trusted and respected. Perinatal palliative care should be available to pregnant mothers whose anomalous fetus is carried to birth.
Video Podcast: https://youtu.be/9pBi4S3xNi0
There are letters to the editor on this invited review by Akinmoladun on pages 988–989 and Brody on pages 990 and Zareba and Al Awar on page 991‐992 of this issue.
Before 2002, there were an estimated 3.4 fatal reactions per year to subcutaneous allergen immunotherapy (SCIT). Recent incidences of SCIT-related systemic allergic reactions (SR) and fatal reactions ...are not well defined.
To define the incidence of and clinical practices associated with SRs to SCIT and skin testing.
From 2008 to 2012, 27% to 49% of the American College of Allergy, Asthma, and Immunology and American Academy of Allergy, Asthma, and Immunology members completed an annual survey of SCIT-related fatal and nonfatal SRs of varying severity. A shortened version of the World Allergy Organization (WAO) classification system for SRs was adopted in 2011 (grade 1, mild; grade 2, moderate; grade 3, severe; grade 4, very severe). From 2011 to 2012, data were collected regarding nonfatal SRs to skin testing and strategies to lower the risk of SRs from SCIT.
Between 2008 and 2012, data were gathered on 23.3 million injection visits. One confirmed fatality occurred in 2009. Overall SR rates remained stable at 0.1%. The rate of very severe, WAO grade 4, SRs was similar to previously reported rates of near-fatal reactions (1 in 1 million injections). Although almost one-third of practices experienced at least 1 SR from skin testing, no WAO grade 3 or 4 SRs from skin testing were reported. A lower target dose during cluster buildup before transitioning to maintenance may be associated with a lower risk of WAO grade 3 SRs (P = .07). Dose adjustment during pollen seasons was associated with fewer WAO grade 3 or 4 SRs (P < .001).
Although SR rates have remained stable and fatalities appear to be declining, continued vigilance regarding SCIT safety is recommended. Additional surveillance and study regarding methods to decrease the risk of severe SRs is warranted.
The objective of this study was to determine whether hatha yoga is an efficacious adjunctive intervention for individuals with continued depressive symptoms despite antidepressant treatment.
We ...conducted a randomized controlled trial of weekly yoga classes (n = 63) v. health education classes (Healthy Living Workshop; HLW; n = 59) in individuals with elevated depression symptoms and antidepressant medication use. HLW served as an attention-control group. The intervention period was 10 weeks, with follow-up assessments 3 and 6 months afterwards. The primary outcome was depression symptom severity assessed by blind rater at 10 weeks. Secondary outcomes included depression symptoms over the entire intervention and follow-up periods, social and role functioning, general health perceptions, pain, and physical functioning.
At 10 weeks, we did not find a statistically significant difference between groups in depression symptoms (b = -0.82, s.e. = 0.88, p = 0.36). However, over the entire intervention and follow-up period, when controlling for baseline, yoga participants showed lower levels of depression than HLW participants (b = -1.38, s.e. = 0.57, p = 0.02). At 6-month follow-up, 51% of yoga participants demonstrated a response (⩾50% reduction in depression symptoms) compared with 31% of HLW participants (odds ratio = 2.31; p = 0.04). Yoga participants showed significantly better social and role functioning and general health perceptions over time.
Although we did not see a difference in depression symptoms at the end of the intervention period, yoga participants showed fewer depression symptoms over the entire follow-up period. Benefits of yoga may accumulate over time.
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