Do soccer players play the mixed-strategy Nash equilibrium?

Mixed-strategy Nash equilibrium (MSNE) is a commonly-used solution concept in game-theoretic models in various fields in economics, management, and other disciplines, but the experimental results whether the MSNE predicts well actual play in games is mixed. Consequently, evidence for naturally-occurring games in which the MSNE predicts the outcome well is of great importance, as it can justify the vast use of MSNE in models. The game between the kicker and goalkeeper in soccer penalty kicks is a real-world game that can be used to examine the application of the MSNE concept or its accuracy because payoffs are a common knowledge, the players have huge incentives to play correctly, the game is simple enough to analyze, its Nash equilibrium is in mixed strategies, and players' actions can be observed. We collected and analyzed data on the direction of kicks and jumps in penalty kicks in various top leagues and tournaments. Our analysis suggests that the MSNE predictions are the closest to the actual sample data, even though some other prediction methods use information on the marginal distribution of kicks or jumps whereas the MSNE does not.Soccer; Football; MSNE; Mixed-strategies; Mixed-strategy Nash equilibrium; Sports; Penalty kicks

Under the Swinging Bridge

Nighttime photo of bridge at Messiah Universit

Action bias among elite soccer goalkeepers: The case of penalty kicks

In soccer penalty kicks, goalkeepers choose their action before they can clearly observe the kick direction. An analysis of 286 penalty kicks in top leagues and championships worldwide shows that given the probability distribution of kick direction, the optimal strategy for goalkeepers is to stay in the goal's center. Goalkeepers, however, almost always jump right or left. We propose the following explanation for this behavior: because the norm is to jump, norm theory (Kahneman and Miller, 1986) implies that a goal scored yields worse feelings for the goalkeeper following inaction (staying in the center) than following action (jumping), leading to a bias for action. The omission bias, a bias in favor of inaction, is reversed here because the norm here is reversed - to act rather than to choose inaction. The claim that jumping is the norm is supported by a second study, a survey conducted with 32 top professional goalkeepers. The seemingly biased decision making is particularly striking since the goalkeepers have huge incentives to make correct decisions, and it is a decision they encounter frequently. Finally, we discuss several implications of the action/omission bias for economics and management.Decision Making; Uncertainty; Choice Behavior; Sport Psychology; Behavioral Economics; Action Bias; Omission Bias; Commission Bias; Action Effect; Inaction Effect; Actor Effect; Economic Psychology; Heuristics and Biases; Soccer; Goalkeepers; Penalty Kicks; Risk; Norms

The earliest earwigs in amber (Dermaptera): A new genus and species from the Early Cretaceous of Lebanon

This is the publisher's version, also available electronically from http://booksandjournals.brillonline.com/.Rhadinolabis phoenicica Engel, Ortega-Blanco & Azar gen. et sp.n. is described and figured from two female earwigs preserved in Early Cretaceous amber from Lebanon, representing the oldest Dermaptera in amber. In addition a partial nymph is recorded from the same deposits. The placement of the genus among Neodermaptera is briefly discussed

Studies of renal autoregulation in pancreatectomized and streptozotocin diabetic rats

Studies of renal autoregulation in pancreatectomized and streptozotocin diabetic rats. We studied renal autoregulation in pancreatectomized Munich-Wistar diabetic rats and in their sham-operated controls. In a second experiment we studied renal autoregulation in untreated and insulin treated streptozotocin diabetic Munich-Wistar rats and their nondiabetic controls. In the first experiment the diabetic rats had higher baseline renal blood flows (RBF). There was a fall in renal vascular resistance (RVR) and sustained RBF in both diabetic and control rats as renal perfusion pressures (RPP) was reduced from 130 and 110mm Hg. As RPP was reduced from 110 and 80mm Hg, there was no significant change in RVR in control rats and RBF began to fall. Below RPP of 80mm Hg RVR rose and RBF fell sharply in these rats. In contrast, there was a progressive fall in RVR as RPP was lowered to 60mm Hg in the diabetic rats and, thus, RBF was much better sustained in these animals. In the second experiment the plasma glucose level was 502 ± 52 mg/dl (X ± SD) in the untreated diabetic rats and only modestly reduced to 411 ± 49 mg/dl in the insulin treated animals. Untreated streptozotocin diabetic rats had moderately reduced and insulin-treated diabetic rats had mildly reduced baseline RVR and RBF. However, in these animals as in the pancreatectomized rats the increases in RVR noted in control rats at subautoregulatory RPPs were not seen. Thus, regardless of whether baseline RBFs were increased or decreased, diabetic rats sustained RBF at markedly reduced RPPs far more efficiently than did nondiabetic rats. The pathogenesis of these abnormalities in diabetic rats was not learned in these studies. However, it is likely that further study of autoregulation in diabetic rats could uncover factors influencing renal vascular tone which would be helpful in understanding the renal hemodynamic perturbations which may attend this experimental model

RNA-Seq identifies genes whose proteins are upregulated during syncytia development in murine C2C12 myoblasts and human BeWo trophoblasts

The fusion of villous cytotrophoblasts into the multinucleated syncytiotrophoblast is critical for the essential functions of the mammalian placenta. Using RNA-Seq gene expression, quantitative protein expression, and siRNA knockdown we identified genes and their cognate proteins which are similarly upregulated in two cellular models of mammalian syncytia development (human BeWo cytotrophoblast to syncytiotrophoblast and murine C2C12 myoblast to myotube). These include DYSF, PDE4DIP, SPIRE2, NDRG1, PLEC, GPR146, HSPB8, DHCR7, and HDAC5. These findings provide avenues for further understanding of the mechanisms underlying mammalian placental syncytiotrophoblast development

A new family of Coreoidea from the Lower Cretaceous Lebanese amber (Hemiptera: Pentatomomorpha)

This is the publisher's version, also available electronically from http://www.degruyter.com.A new genus and species, Yuripopovina magnifica, belonging to a new coreoid family, Yuripopovinidae (Hemiptera: Pentatomomorpha), is described and illustrated from the Lower Cretaceous amber of Lebanon. The species represents the first definitive Mesozoic record for the Coreoidea. A cladistic analysis of Coreoidea, including the new family, is undertaken

A soil-carrying lacewing larva in Early Cretaceous Lebanese amber

Diverse organisms protect and camouflage themselves using varied materials from their environment. This adaptation and associated behaviours (debris-carrying) are well known in modern green lacewing larvae (Neuroptera: Chrysopidae), mostly due to the widespread use of these immature insects in pest control. However, the evolutionary history of this successful strategy and related morphological adaptations in the lineage are still far from being understood. Here we describe a novel green lacewing larva, Tyruschrysa melqart gen. et sp. nov., from Early Cretaceous Lebanese amber, carrying a preserved debris packet composed by soil particles entangled among specialised setae of extremely elongate tubular tubercles. The new morphotype has features related to the debris-carrying habit that are unknown from extant or extinct green lacewings, namely a high number of tubular tubercle pairs on the abdomen and tubular tubercle setae with mushroom-shaped endings that acted as anchoring points for debris. The current finding expands the diversity of exogenous materials used by green lacewing larvae in deep time, and represents the earliest direct evidence of debris-carrying in the lineage described to date. The debris-carrying larval habit likely played a significant role during the initial phases of diversification of green lacewings.funded by the Spanish AEI/FEDER, UE Grant CGL2017-84419.R.P.F. is funded by a Research Fellowship from the Oxford University Museum of Natural History.M.S.E. was supported by U.S. National Science Foundation grant DEB- 1144162

Do soccer players play the mixed-strategy Nash equilibrium?

Mixed-strategy Nash equilibrium (MSNE) is a commonly-used solution concept in game-theoretic models in various fields in economics, management, and other disciplines, but the experimental results whether the MSNE predicts well actual play in games is mixed. Consequently, evidence for naturally-occurring games in which the MSNE predicts the outcome well is of great importance, as it can justify the vast use of MSNE in models. The game between the kicker and goalkeeper in soccer penalty kicks is a real-world game that can be used to examine the application of the MSNE concept or its accuracy because payoffs are a common knowledge, the players have huge incentives to play correctly, the game is simple enough to analyze, its Nash equilibrium is in mixed strategies, and players' actions can be observed. We collected and analyzed data on the direction of kicks and jumps in penalty kicks in various top leagues and tournaments. Our analysis suggests that the MSNE predictions are the closest to the actual sample data, even though some other prediction methods use information on the marginal distribution of kicks or jumps whereas the MSNE does not