Coöperatie in spelshows

In this chapter, we argue that game shows can be a useful source of data to study cooperative behavior. The unique combination of well-defined decision problems and large stakes makes game show data complementary to both experimental and field data. Over the past years, a number of TV shows have employed a vari- ant of the prisoner’s dilemma. We summarize the results of five different studies that use these shows to test a broad range of hypotheses. Finally, we discuss caveats of game show data, and contend that the potential problems are mostly not very different from those with experimental and field data

Coöperatie in spelshows

In this chapter, we argue that game shows can be a useful source of data to study cooperative behavior. The unique combination of well-defined decision problems and large stakes makes game show data complementary to both experimental and field data. Over the past years, a number of TV shows have employed a vari- ant of the prisoner’s dilemma. We summarize the results of five different studies that use these shows to test a broad range of hypotheses. Finally, we discuss caveats of game show data, and contend that the potential problems are mostly not very different from those with experimental and field data

The Wisdom of the Inner Crowd in Three Large Natural Experiments

The quality of decisions depends on the accuracy of estimates of relevant quantities. According to the wisdom of crowds principle, accurate estimates can be obtained by combining the judgements of different individuals 1,2. This principle has been successfully applied to improve, for example, economic forecasts 3-5, medical judgements 6-9 and meteorological predictions 10-13. Unfortunately, there are many situations in which it is infeasible to collect judgements of others. Recent research proposes that a similar principle applies to repeated judgements from the same person 14. This paper tests this promising approach on a large scale in a real-world context. Using proprietary data comprising 1.2 million observations from three incentivized guessing competitions, we find that within-person aggregation indeed improves accuracy and that the method works better when there is a time delay between subsequent judgements. However, the benefit pales against that of between-person aggregation: the average of a large number of judgements from the same person is barely better than the average of two judgements from different people

The cytocompatibility and early osteogenic characteristics of an injectable calcium phosphate cement.

In this study, the cytocompatibility and early osteogenic characteristics of rat bone marrow cells (RBMCs) on injectable calcium phosphate (CaP) cement (Calcibon) were investigated. In addition to unmodified CaP cement discs, 2 other treatments were given to the discs: preincubation in MilliQ and sintering at different temperatures. After primary culture, RBMCs were dropwise seeded on the discs and cultured for 12 days. The samples were evaluated in terms of cell viability, morphology (live and dead assays and scanning electron microscopy (SEM)), cell proliferation (deoxyribonucleic acid (DNA) analyses), early cell differentiation (alkaline phosphatase (ALP) activity), and physicochemical analyses (xray diffraction (XRD)). The live and dead, DNA, and SEM results showed that Calcibon discs without any additional treatment were not supporting osteoblast-like cells in vitro. There were fewer cells, and cell layers were detached from the disc surface. Therefore, different preincubation periods and sintering temperatures were evaluated to improve the cytocompatibility of the CaP cement. Preincubating discs in MilliQ for periods of 1, 4, 8, and 12 weeks resulted in the hydrolysis of a-tri calcium phosphate (TCP) into an apatite-like structure with some b-TCP, as shown with XRD, but the material was not cytocompatible. Sintering the discs between 8008C and 11008C resulted in conversion of a-TCP to b-TCP with some hydroxyapatite and an increase in crystallinity. Eventually, the discs sintered at 11008C achieved better cell attachment, more-abundant cell proliferation, and earlier differentiation than other sintered (6008C, 8008C, and 10008C), preincubated, and unmodified specimens. On basis of our results, we conclude that in vivo results with CaP-based cements do not guarantee in vitro applicability. Furthermore, unmodified Calcibon is not cytocompatible in vitro, although preincubation of the material results in a more-favorable cell response, sintering of the material at 11008C results in the best osteogenic properties. In contrast to in vivo studies, the Calcibon CaP cement is not suitable as a scaffold for cellbased tissue-engineering strategies

Can the Market Divide and Multiply? A Case of 807 Percent Mispricing

This paper documents a strong violation of the law of one price surrounding a large rights issue. If prices are right, the relation between the prices of shares and rights follows the outcome of a simple calculation. In the case of Royal Imtech N.V. in 2014, prices deviated sharply and persistently from the theoretical prediction. Throughout the term of the rights, investors were buying shares at prices that were many times what they should have been given the price of the rights. Short-selling constraints in the form of high recall risk and lacking stock lending supply are the most likely explanation for the failure of arbitrage as a safeguard of market efficiency. Still, it remains remarkable that investors were buying large volumes of shares at highly inflated prices in the presence of a cheap, perfect substitute

Bone regenerative properties of injectable PGLA-CaP composite with TGF-beta1 in a rat augmentation model.

The aim of this study was to examine the bone augmentation properties of an injectable composite consisting of PLGA microspheres/CaP cement (20/80), and the additional effect of loading PLGA microspheres with TGF-β1 (200 ng). For this purpose, PLGA/CaP composites (control) and PLGA/CaP composites loaded with TGF-β1 (test group) were injected on top of the skulls of 24 Wistar rats. Each rat received 2 materials from the same experimental group, and in total 48 implants were placed (n = 8). After 2, 4, and 8 weeks the results were evaluated histologically and histomorphometrically. The contact length between the implants and newly formed bone increased in time, and was significantly higher for the TGF-β1-loaded composites after 2 weeks. Also, bone formation was significantly higher for the TGF-β1-loaded composites (18.5% ± 3) compared to controls (7.21% ± 5) after 8 weeks of implantation. Immunohistochemical staining demonstrated massive inflammatory infiltrates in both groups, particularly at 2 weeks, which decreased substantially at 4 and 8 weeks. In conclusion, injectable PLGA/CaP composites stimulated bone augmentation in a rat model. The addition of TGF-β1 to the composite significantly increased bone contact at 2 weeks and enhanced new bone formation at 8 weeks

Standing united or falling divided? High stakes bargaining in a TV game show

We examine high stakes three-person bargaining in a game show where contestants bargain over a large money amount that is split into three unequal shares. We find that individual behavior and outcomes are strongly influenced by equity concerns: those who contributed more to the jackpot claim larger shares, are less likely to make concessions, and take home larger amounts. Contestants who announce that they will not back down do well relative to others, but they do not secure larger absolute amounts and they harm others. There is no evidence of a first-mover advantage and little evidence that demographic characteristics matter

Incentives, Performance and Choking in Darts

This paper examines the effect of incentives on the performance of darts players. We analyze four data sets comprising a total of 123,402 darts matches of professional, amateur, and youth players. The game of darts offers an attractive natural research setting, because performance can be observed at the individual level and without the obscuring effects of risk considerations and the behavior of others. We find that amateur and youth players perform better under moderately higher incentives, but choke when the incentives are really high. Professional players similarly display better performance under higher incentives, but appear less susceptible of choking. These results speak to a growing literature on the limits of increasing incentives as a recipe for better performance

Gender and Willingness to Compete for High Stakes

We examine gender differences in willingness to compete, using data from a TV game show where in each episode the winner of an elimination competition in expectation wins hundreds of thousands of euros. At several stages of the elimination competition, contestants face a choice between continuing to compete and opting out in exchange for a comparatively modest prize. When there is no strategic interaction embedded in this choice, we observe the well-known pattern that women compete less than men, but this difference derives entirely from women avoiding competition against men. When there is strategic interaction and contestants should factor in their opponents’ willingness to compete, women again tend to avoid competing against men; men then seem to anticipate the lower competitiveness of female opponents, as evidenced by their greater propensity to compete against women. Ability differences are unlikely to explain these results. Our findings show that the gender difference in willingness to compete that is well-documented in the experimental economics literature also occurs in a quasi-experimental real-world setting with exceptionally high stakes, and underline the importance of the gender of competitors

Does Losing Lead to Winning? An Empirical Analysis for Four Sports

Berger and Pope (2011) show that being slightly behind increases the likelihood of winning in professional (National Basketball Association; NBA) and collegiate (National Collegiate Athletic Association; NCAA) basketball. We extend their analysis to large samples of Australian football, American football, and rugby matches, but find no evidence of such an effect for these three sports. When we revisit the phenomenon for basketball, we only find supportive evidence for NBA matches from the period analyzed in Berger and Pope (2011). There is no significant effect for NBA matches from outside this sample period, for NCAA matches, or for matches from the Women’s National Basketball Association. High-powered meta-analyses across the different sports and competitions do not reject the null hypothesis of no effect of being slightly behind on winning. The confidence intervals suggest that the true effect, if existent at all, is likely relatively small