This paper considers the optimal design of dynamic research contests when the buyer can set time-dependent prizes. We derive the buyer-optimal contest and show that it entails an increasing prize schedule. Remarkably, this allows the buyer to implement a global stopping rule. In particular, the optimal contest attains the first-best. More generally, we show that global stopping rules can be implemented robustly and compare them to individual stopping rules which have been analyzed in the existing literature. We conclude by discussing policy implications of our findings and highlight that global stopping rules combine the best aspects of innovation races and research tournaments.
Increased responding to drug-associated stimuli (cue reactivity) and an inability to tolerate delayed gratification (reward impulsivity) have been implicated in the development and maintenance of drug addiction. Whereas data from animal studies suggest that both the dopamine and opioid system are involved in these two reward-related processes, their role in humans is less clear. Moreover, dopaminergic and opioidergic drugs have not been directly compared with regard to these functions, even though a deeper understanding of the underlying mechanisms might inform the development of specific treatments for elevated cue reactivity and reward impulsivity. In a randomized, double-blind, between-subject design we administered the selective dopamine D2/D3 receptor antagonist amisulpride (400 mg, n=41), the unspecific opioid receptor antagonist naltrexone (50 mg, n=40) or placebo (n=40) to healthy humans and measured cue-induced responding with a Pavlovian-instrumental transfer task and reward impulsivity with a delay discounting task. Mood was assessed using a visual analogue scale. Compared with placebo, amisulpride significantly suppressed cue-induced responding and reward impulsivity. The effects of naltrexone were similar, although less pronounced. Both amisulpride and naltrexone decreased average mood ratings compared with placebo. Our results demonstrate that a selective blockade of dopamine D2/D3 receptors reduces cue-induced responding and reward impulsivity in healthy humans. Antagonizing μ-opioid receptors has similar effects for cue-induced responding and to a lesser extent for reward impulsivity.
Successful avoidance of aversive outcomes is crucial for the survival of animals. Although accumulating evidence indicates that an indirect pathway in the basal ganglia is involved in aversive behavior, the ventral pallidum (VP), which is an important component of this pathway, has so far been implicated primarily in appetitive behavior. In this study, we used single-cell recordings and bicuculline (GABAA antagonist) injections to elucidate the role of VP both in the encoding of aversive context and in active avoidance. We found 2 populations of neurons that were preferentially activated by appetitive and aversive conditioned stimuli (CSs). In addition, VP showed appetitive and aversive outcome anticipatory activities. These activity patterns indicate that VP is involved in encoding and maintaining CS-induced aversive contextual information. Furthermore, the disturbance of VP activity by bicuculline injection increased the number of error trials in aversive trials. In particular, the subjects released the response bar prematurely, showed no response at all, or failed to avoid the aversive outcome. Overall, these results suggest that VP plays a central role in controlling CS-induced negative motivation to produce avoidance behavior.
Many recent studies point to increasing inequality in mortality in the United States over the past 20 years. These studies often use mortality rates in middle and old age. We used poverty level rankings of groups of U.S. counties as a basis for analyzing inequality in mortality for all age groups in 1990, 2000, and 2010. Consistent with previous studies, we found increasing inequality in mortality at older ages. For children and young adults below age 20, however, we found strong mortality improvements that were most pronounced in poorer counties, implying a strong decrease in mortality inequality. These younger cohorts will form the future adult U.S. population, so this research suggests that inequality in old-age mortality is likely to decline.
OBJECTIVE We analyse temporal trends and regional variation among the most recent available anthropometric data from German conscription in the years 2008-2010 and their historical contextualization since 1956. Design/setting/subjects The overall sample included German conscripts (N 13 857 313) from 1956 to 2010. RESULTS German conscripts changed from growing in height to growing in breadth. Over the analysed 54 years, average height of 19-year-old conscripts increased by 6·5 cm from 173·5 cm in 1956 (birth year 1937) to 180·0 cm in 2010 (birth year 1991). This increase plateaued since the 1990s (1970s birth years). The increase in average weight, however, did not lessen during the last two decades but increased in two steps: at the end of the 1980s and after 1999. The weight and BMI distributions became increasingly right-skewed, the prevalence of overweight and obesity increased from 11·6 % and 2·1 % in 1984 to 19·9 % and 8·5 % in 2010, respectively. The north-south gradient in height (north = taller) persisted during our observations. Height and weight of conscripts from East Germany matched the German average between the early 1990s and 2009. Between the 1980s and the early 1990s, the average chest circumference increased, the average difference between chest circumference when inhaling and exhaling decreased, as did leg length relative to trunk length. CONCLUSIONS Measuring anthropometric data for military conscripts yielded year-by-year monitoring of the health status of young men at a proscribed age. Such findings contribute to a more precise identification of groups at risk and thus help with further studies and to target interventions.
Extensive cleaning or checking of patients with obsessive-compulsive disorder (OCD) are often interpreted as strategies to avoid harm and as an expression of the widespread belief that OCD patients are more risk-averse. However, despite its clinical significance, the neural basis of risk attitude in OCD is unknown. Here, we investigated neural activity during risk processing using functional magnetic resonance imaging and simultaneously assessed risk attitude using a separate behavioral paradigm in OCD patients with different symptoms versus healthy controls (HCs). We found opposite insula responses to high versus low risk in OCD patients compared to HCs: a positive correlation between insula activity and risk-aversion in patients versus a negative correlation in controls. Although OCD patients overall were not more risk-averse than controls, there were differences between subgroups of OCD patients: patients with doubt/checking symptoms were more risk-averse than other patients. Taken together, OCD patients show a reversed pattern of risk processing by the insula compared to HCs. Moreover, the data suggest that increased activation of the insula signals an abnormal urge to avoid risks in the subpopulation of OCD patients with doubt and checking symptoms. These results indicate a role for the insula in excessive risk-avoidance relevant to OCD.
Die Gesundheitsökonomin Anna Sax legt mit «Einheitskasse – warum nicht?» eine Wirkungsanalyse von Wettbewerb und Einheitskasse in der Schweizer Krankenversicherung vor. Der selbst deklarierte Anspruch dieser von der SP Bundeshaus-Fraktion in Auftrag gegebenen Studie ist hoch: Ständerätin Egerszegi verspricht im Vorwort eine Prüfung des Modells einer «öffentlichen Krankenkasse für die Grundversicherung ohne ideologische Scheuklappen» (S. 5), «nicht nur Zündstoff, sondern vor allem Fakten» (S. 6) und gemäss Sax (S. 9) besteht das Ziel darin, «in erster Linie den Leserinnen und Lesern zu ermöglichen, sich ein differenziertes Urteil zu bilden.»
We propose that heterogeneous asset trading behavior is the result of two distinct, non-convertible mental dimensions: analytical (“quantitative”) capability and mentalizing (“perspective-taking”) capability. We develop a framework of mental capabilities that yields testable predictions about individual trading behavior, revenue distribution and aggregate outcomes. The two-dimensional structure of mental capabilities predicts the existence of four mental types with distinguishable trading patterns and revenues. Individuals will trade most successfully if and only if they have both capabilities. On the other hand, subjects who can mentalize well but have poor analytical capability will suffer the largest losses. As a consequence, being able in just one dimension does not assure trading success. We test these implications in a laboratory environment, where we first independently elicit subjects’ capabilities in both dimensions and then conduct a standard asset market experiment. We find that individual trading gains and patterns are consistent with our theoretical predictions. Our results suggest that two mental dimensions are necessary to encompass the complex heterogeneous behaviors in asset markets; a one-dimensional measure of mental capability will lead to biased conclusions. The findings have potential implications for financial institutions, which can use the measures to select successful traders, or for policy-makers, helping them to prevent the formation of asset bubbles. Finally, our conceptual framework and the empirical screening method could be applied to explain heterogeneous behavior in other games.
Work and trade relationships are often governed by relational contracts, in which incentives for cooperative action today stem from the prospective future benefits of the relationship. In this paper, we study how reductions in clarity about the financial consequences of actions, induced by incomplete information about the costs of providing quality, affect relational contracts in buyer-seller relation- ships. Under incomplete information, payoffs to actions become private infor- mation. This can impede the joint understanding of what constitutes cooperative behavior, and may thus inject mistrust into relationships, even if credibility is held constant. Comparing seller-buyer relationships with and without complete infor- mation about seller costs in the laboratory, we find that such a lack of clarity has effects on the terms of relational contracts. However, these effects only concern the distribution of rents, and not efficiency.
Background: In Switzerland, age is the predominant driver of solidarity transfers in risk adjustment (RA). Concerns have been voiced regarding growing imbalances in cost sharing between young and old insured due to demographic changes (larger fraction of elderly >65 years and rise in average age). Particularly young adults aged 19–25 with limited incomes have to shoulder increasing solidarity burdens. Between 1996 and 2011, monthly inter generational solidarity payments for young adults have doubled from CHF 87 to CHF 182, which corresponds to the highest absolute transfer increase of all age groups.
Results: By constructing models for age-specific RA growth and for calculating the lifetime sum of RA transfers we investigated the causes and consequences of demographic changes on RA payments. The models suggest that the main driver for RA increases in the past was below average health care expenditure (HCE) growth in young adults, which was only half as high (average 2% per year) compared with older adults (average 4% per year). Shifts in age group distributions were only accountable for 2% of the CHF 95 rise in RA payments.
Despite rising risk adjustment debts for young insured the balance of lifetime transfers remains positive as long as HCE growth rates are greater than the discount rate used in this model (3%). Moreover, the life-cycle model predicts that the lifetime rate of return on RA payments may even be further increased by demographic changes.
Nevertheless, continued growth of RA contributions may overwhelm vulnerable age groups such as young adults. We therefore propose methods to limit the burden of social health insurance for specific age groups (e.g. young adults in Switzerland) by capping solidarity payments.
Conclusions: Taken together, our mathematical modelling framework helps to gain a better understanding of how demographic changes interact with risk adjustment and how redistribution of funds between age groups can be controlled without inducing further selection incentives. Those methods can help to construct more equitable systems of health financing in light of population aging.
