Daniel Friedman

Human players in our laboratory experiment converge closely to the symmetric mixed Nash equilibrium when matched in a single population version of the standard Hawk-Dove game. When matched across two populations, the same players show clear movement towards an asymmetric (and very inequitable) pure Nash equilibrium of the same game. These �ndings support a distinctive prediction of evolutionary game theory.

We study prisoners' dilemmas played in continuous time with flow payoffs accumulated over 60 seconds. In most cases, the median rate of mutual cooperation is about 90 percent. Control sessions with repeated matchings over eight subperiods achieve less than half as much cooperation, and cooperation rates approach zero in one-shot sessions. In follow-up sessions with a variable number of subperiods, cooperation rates increase nearly linearly as the grid size decreases, and, with one-second subperiods, they approach continuous levels. Our data support a strand of theory that explains how capacity to respond rapidly stabilizes cooperation and destabilizes defection in the prisoner's dilemma. (JEL C72, C78, C91)

ABSTRACT The authors report successive rounds of theory and laboratory experiments investigating price-taking behavior and market efficiency. They focus on the impact of structural parameters as well as trading institution. The structural parameters involve noncompetitive supply and demand, and a new odd-lot trading procedure for divisible goods. The trading institutions include the continuous double auction and the one-shot clearinghouse as well as a new quantities-only clearinghouse institution. The authors present and justify an as-if complete information theory that explains the competitive outcomes and that correctly predicts highly noncompetitive outcomes in quantities-only clearinghouse markets. Copyright 1995 by Royal Economic Society.

The current study examined whether negative illness perceptions help explain the link between depression and quality of life. Seventy patients with epilepsy completed standardized self-report questionnaires measuring depression, illness perception, and quality of life (QOL). Illness perception statistically mediated the relationship between depression and QOL (Indirect effect (CI; confidence interval) = -.72, lower limit = -1.7, upper limit = -.22, p < .05). Results held with and without adjusting for potential confounding variables (age, sex, ethnicity, income, and seizure frequency) and when operationalizing depression as a continuous variable that indexed severity of symptoms or as a dichotomous variable that indexed criteria consistent with a diagnosis of major depressive disorder. This study is the first to suggest that illness perceptions may be a useful target in screening and intervention approaches in order to improve QOL among low-income, racially/ethnically diverse pat...

Sudden unexpected death in epilepsy (SUDEP) is likely to be the most common cause of disease-related mortality in people with epilepsy. The most commonly encountered scenario is that a previously healthy person is found dead in bed by family. Patients with frequent generalized tonic-clonic seizures are at highest risk but SUDEP can occur in patients who have never had convulsions. The mechanisms of SUDEP are poorly understood but seem to be related to seizure-related cardiac, respiratory or cerebral dysfunction. Seizure control is the only clear strategy to prevent SUDEP but that is not possible in the 30 % of patients with treatment-resistant epilepsy. Understanding the pathophysiology of SUDEP may lead to prevention strategies for patients who continue to have seizures despite maximal therapy.

GaInAsN cells are measured to retain 93 ± 3% and 89 ± 4% of their original efficiency after exposure to 5 × 1014 and 1 × 1015 cm-2 1-MeV electrons, respectively. The rate of degradation is not correlated with the performance at beginning of life (BOL). The depletion width remains essentially unchanged, increasing by < 1%. Temperature-coefficient data for GaInAsN

Obra en que se explican los principales conceptos relativos a los lenguajes de programación, desde un punto de vista analítico, a la vez que se da la semántica de muchos elementos de los lenguajes que son ejecutables de manera directa. Contenido: Conjunto de datos inductivos; Abstracción de datos; Intérpretes del paso de ambiente; Tipos; Objetos y clases; Objetos y tipos; Intérpretes de paso continuo; Estilo de paso continuo.

Epilepsy surgery is the most effective treatment for select patients with drug-resistant epilepsy. In this article, we aim to provide an accurate understanding of the current epidemiologic characteristics of this intervention, as this knowledge is critical for guiding educational, academic, and resource priorities. We profile the practice of epilepsy surgery between 1991 and 2011 in nine major epilepsy surgery centers in the United States, Germany, and Australia. Clinical, imaging, surgical, and histopathologic data were derived from the surgical databases at various centers. Although five of the centers performed their highest number of surgeries for mesial temporal sclerosis (MTS) in 1991, and three had their highest number of MTS surgeries in 2001, only one center achieved its peak number of MTS surgeries in 2011. The most productive year for MTS surgeries varied then by center; overall, the nine centers surveyed performed 48% (95% confidence interval [CI] -27.3% to -67.4%) fewer such surgeries in 2011 compared to either 1991 or 2001, whichever was higher. There was a parallel increase in the performance of surgery for nonlesional epilepsy. Further analysis of 5/9 centers showed a yearly increase of 0.6 ± 0.07% in the performance of invasive electroencephalography (EEG) without subsequent resections. Overall, although MTS was the main surgical substrate in 1991 and 2001 (proportion of total surgeries in study centers ranging from 33.3% to 70.2%); it occupied only 33.6% of all resections in 2011 in the context of an overall stable total surgical volume. These findings highlight the major aspects of the evolution of epilepsy surgery across the past two decades in a sample of well-established epilepsy surgery centers, and the critical current challenges of this treatment option in addressing complex epilepsy cases requiring detailed evaluations. Possible causes and implications of these findings are discussed.

This pap er develops a theory of revealed preferences over oneís own and othersímonetary payo§s. We intro duce ìmore altruistic thanî(MAT), a partial ordering over preferences, and interpret it with known parametric mo dels. We also intro duce and illustrate ìmore generous thanî (MGT), a partial ordering over opp ortunity sets. Several recent discussions of altruism fo cus on two

Chronic kidney disease (CKD) severity is associated with increased morbidity and mortality in congestive heart failure (CHF). There is a paucity of data regarding renal improvement after cardiac resynchronization therapy (CRT) and its potential impact on clinical outcomes, especially in patients with severe CKD. This was a retrospective analysis of a prospectively collected cohort of 260 patients with CKD undergoing CRT at a single center. Renal function was compared before and after CRT. The primary endpoint was a composite of death, heart transplant, and LVAD, assessed at 5 years. Patients with more severe CKD demonstrated increased risk of death, transplant, or LVAD following CRT (p = 0.015). Renal response (eGFR improvement ≥ 10mL/min/1.73m(2) ) was observed in 14% of all patients and 28% of patients with stage IV CKD. Independent predictors of renal response included LVEF improvement (OR 1.06, CI 1.01-1.10), ACE inhibitor/ARB use (OR 4.31, CI 1.08-17.23), and advanced CKD stage (OR 2.19, CI 1.14-4.23). Renal response independently decreased hazard of the primary outcome (HR 0.24, CI 0.08-0.73, p = 0.01). Renal responders with stage IV CKD had 80% five-year event-free survival, compared to 0% for non-renal responders in stage IV (p = 0.03). Although severity of CKD is associated with poorer outcome after CRT, improvement in renal function can occur in patients across all CKD stages. Renal responders, including those with stage IV CKD, demonstrate favorable five-year outcomes. Assessment of renal response may help better prognostic outcomes following CRT. This article is protected by copyright. All rights reserved.

This paper develops a nonparametric theory of preferences over one's own and others' monetary payoffs. We introduce "more altruistic than" (MAT), a partial ordering over such preferences, and interpret it with known parametric models. We also introduce and illustrate "more generous than" (MGT), a partial ordering over opportunity sets. Several recent studies focus on two-player extensive form games of complete

We develop a financial market model focused on fund managers who continuously adjust their exposure to risk in response to the payo gradient. The base model has a stable equilibrium with classic properties. However, bubbles and crashes occur in extended models incorporating an endogenous market risk premium based on investors' historical losses and constant gain learning. When losses have been

Over the past few decades, experimental methods have given economists access to new sources of data and enlarged the set of economic propositions that can be validated. This field has grown exponentially in the past few decades, but is still relatively new to the average Indian ...

Presented at the 2001 NCPV Program Review Meeting: Comparison of use of TMB, TEB, and BF3 to diborane for MOCVD growth of BGaInAs. BGaInAs can potentially be used in strain-free high-efficiency III-V solar cells, but the growth of sufficiently high-quality epitaxial BGaInAs using diborane has proven difficult. We compare the use of alternative boron precursors (trimethylboron [TMB], triethylboron [TEB], and

Despite growing interest in traditional and Internet auctions, the marketing literature on auctions is sparse. This paper outlines selected aspects of the research opportunity. We provide a brief description of the major auction mechanisms, outline key concepts and results from the economic analysis of auctions, and summarize the key findings in empirical tests of auction theory. We then identify areas for future research on auction markets, particularly those of interest to marketers in the new contexts created by the Internet.

III-V semiconductors grown on silicon substrates are very attractive for lower-cost, high-efficiency multijunction solar cells, but lattice-mismatched alloys that result in high dislocation densities have been unable to achieve satisfactory performance. GaNxP1-x-yAsy is a direct-gap III-V alloy that can be grown lattice-matched to Si when y= 4.7x - 0.1. We have proposed the use of lattice-matched GaNPAs on silicon for

We considered whether a subset of children with sudden unexplained death in childhood (SUDC) and a history of febrile seizures (FS) may parallel those in sudden unexpected death in epilepsy (SUDEP). The prevalence of a history of FS was examined, and factors that may distinguish SUDC cases with and without FS were described. Characteristics were assessed in 123 consecutive children with SUDC reported to the SUDC program (4/1/11-3/31/14) by their parents. Parental interview covered the decedent's medical history, circumstances of death, environmental factors, cause of death, and family medical history. Features of SUDC cases were compared by FS history. Overall, 31.7% of SUDC cases had a history of FS, among which 74.4% had simple FS. Compared to those without a history of FS, a history of FS was associated with a greater median age at death (p = 0.03) and death during the weekdays (p = 0.02). Terminal fever was similar in those with and without FS. The median time from FS to death was 6.0 months (interquartile range [IQR] 3.0-10.0). In all SUDC cases, prone position at death, death during sleep, and unwitnessed deaths predominated. There are parallels among SUDC, sudden infant deaths, and sudden unexpected death in epilepsy (SUDEP) with regard to prone position, unwitnessed deaths mostly during sleep, and male predominance. In children with SUDC and a history of FS, terminal fever may increase the risk for an unwitnessed terminal seizure. The greater than expected prevalence of a FS history and the proportion with terminal fever or illness in this cohort suggests that some SUDC deaths may be seizure related and therefore have potential commonalities with SUDEP.

This paper analyzes seller choices and outcomes in approximately 700 recent Internet auctions on eBay. The ‘Buy it Now’ option that is available in these auctions allows the seller to supplement or replace the auction with a posted price offer. We use a structural model to control for the endogenous conduct of the auction (e.g., number of bids and bidders)

In catamenial epilepsy, seizures exhibit a cyclic pattern that parallels the menstrual cycle. Many studies suggest that catamenial seizures are caused by fluctuations in gonadal hormones during the menstrual cycle, but this has been difficult to study in rodent models of epilepsy because the ovarian cycle in rodents, called the estrous cycle, is disrupted by severe seizures. Thus, when epilepsy is severe, estrous cycles become irregular or stop. Therefore, we modified kainic acid (KA)- and pilocarpine-induced status epilepticus (SE) models of epilepsy so that seizures were rare for the first months after SE, and conducted video-EEG during this time. The results showed that interictal spikes (IIS) occurred intermittently. All rats with regular 4-day estrous cycles had IIS that waxed and waned with the estrous cycle. The association between the estrous cycle and IIS was strong: if the estrous cycles became irregular transiently, IIS frequency also became irregular, and when the estrou...

The current study examined psychosocial correlates of medication adherence in a socioeconomically and racially diverse sample of patients with epilepsy. Fifty-five patients with epilepsy completed standardized self-report questionnaires measuring depression, stress, social support, and medication and illness beliefs. Antiepileptic drug (AED) adherence was measured using the 8-item Morisky Medication Adherence Scale 36% reported poor adherence. We tested which psychosocial factors were independently and most strongly associated with AED adherence. Stress and depression were negatively correlated with adherence, while perceived social support was positively correlated with adherence (Ps<.05). When all three of these variables and relevant covariates in a multiple regression model were included, only perceived social support remained a significant predictor of adherence (P=.015). This study is one of the first to suggest the importance of targeting social support in screening and in...

Sudden unexpected death in epilepsy (SUDEP) is a common cause of mortality in patients with the disease, but it is unknown how neurologists disclose this risk when counseling patients. This study aimed at examining SUDEP discussion practices of neurologists in the U.S. and Canada. An electronic, web-based survey was sent to 17,558 neurologists in the U.S. and Canada. Survey questions included frequency of SUDEP discussion, reasons for discussing/not discussing SUDEP, timing of SUDEP discussions, and perceived patient reactions. We examined factors that influence the frequency of SUDEP discussion and perceived patient response using multivariate logistic regression. The participants of this study were neurologists who completed postgraduate training and devoted >5% of their time to patient care. There was a response rate of 9.3%; 1200 respondents met eligibility criteria and completed surveys. Only 6.8% of the respondents discussed SUDEP with nearly all (>90% of the time) of th...

This study aims to validate the joint ACCF/AHA/ESC/WHF Universal Definition of peri-procedural myocardial infarction (PMI) with high sensitivity troponin T (hsTnT). A retrospective cohort study encompassing patients admitted to our institution between May 2012 and April 2013 was performed. 630 patients underwent percutaneous coronary interventions during the study period. Among them, 459 patients met the inclusion criteria and were eligible for analyses. 76.9% of these patients were male, while the mean age was 68.6. PMI was observed in 4.3% of the patients based on the Universal Definition. The predictors of PMI were chronic kidney disease (OR: 3.0, p=0.026), family history of cardiovascular disease (OR: 2.7, p=0.043) and use of IIb/IIIa inhibitors (OR 4.2, p=0.01). MACE was reported in 4.4% of the patients at 12 months, and was significantly and independently associated with PMI (OR 7.3, p=0.003) in a multivariate model which accounted for lesion complexity, patients' baseline clinical information, dual-antiplatelet status at follow-up and various procedural characteristics. The post-procedural hsTnT was much higher in those who suffered MACE than those who did not (156 v.s. 43 ng/L, p<0.001). PMI as defined by the current Universal Definition using hsTnT is an independent predictor of adverse clinical outcome at 12 months in patients undergoing PCI. Accordingly, PMI remains a clinically relevant factor in current practice and should be considered a key outcome measure in clinical trials and a potential target for therapy.

Odor perception depends on a constellation of molecular, cellular, and network interactions in olfactory brain areas. Recently, there has been better understanding of the cellular and molecular mechanisms underlying the odor responses of neurons in the olfactory epithelium, the first-order olfactory area. In higher order sensory areas, synchronized activity in networks of neurons is known to be a prominent feature of odor processing. The perception and discrimination of odorants is associated with fast (20-70 Hz) electroencephalographic oscillations. The cellular mechanisms underlying these fast network oscillations have not been defined. In this study, we show that synchronous fast oscillations can be evoked by brief electrical stimulation in the rat olfactory bulb in vitro, partially mimicking the natural response of this brain region to sensory input. Stimulation induces periodic inhibitory synaptic potentials in mitral cells and prolonged spiking in GABAergic granule cells. Repe...

Recurrent inhibition in olfactory bulb mitral cells is mediated via reciprocal dendrodendritic synapses with granule cells. Although GABAergic granule cells express both NMDA and non-NMDA glutamate receptors, dendrodendritic inhibition (DDI) relies on the activation of NMDA receptors. Using whole-cell recordings from rat olfactory bulb slices, we now show that olfactory NMDA receptors have a dual role; they depolarize granule cell spines, and they provide a source of calcium that can evoke GABA exocytosis. We demonstrate that exogenous NMDA can trigger GABA release after blockade of voltage-dependent calcium channels (VDCCs) with Cd. We also find that postsynaptic depolarization alone can evoke GABA release via a separate mechanism that relies on calcium influx through Cd-sensitive VDCCs. By selectively manipulating postsynaptic responses in granule cells with high-K or low-Na extracellular solutions, we show that endogenous glutamate can elicit GABA release via both NMDA receptor- ...