Playtime
Finally, Evidence for a Momentum Effect in the NBA
Jeremy Arkes & Jose Martinez
Journal of Quantitative Analysis in Sports, July 2011
Abstract:
No previous study on momentum in team sports has found any valid evidence for a momentum effect - i.e., an effect of success in the past few games, over and above the effect of team quality. We develop an econometric model to determine if there is a momentum effect in the NBA by examining how success over the past few games leads to a higher probability of winning the next game. The model takes into account the home vs. away strengths of the teams in the current game as well as their opponents in the previous games (to calculate measures of "adjusted success over the past few games"). Thus, success in previous games is adjusted for quality of the wins or losses. In addition, we account for rest days before the current game for both teams. Using data over three NBA seasons (2007-2009), we find strong evidence for a positive momentum effect.
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Baseball: A Poor Substitute for Football - More Evidence of Sports Gambling as Consumption
Rodney Paul & Andrew Weinbach
Journal of Sports Economics, forthcoming
Abstract:
Due to the use of sports wagering market data as a laboratory to test the Efficient Markets Hypothesis, sports bettors have been assumed to behave as investors. With the rejection of the balanced book hypothesis and the persistent support of market efficiency, the notion of the sports bettor as investor should be in doubt. Using betting volume data from online sportsbooks, bettors are shown to substitute out of baseball betting into football betting when the season starts. The authors argue that these findings are consistent with consumer behavior, but inconsistent with the notion of bettors as investors.
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Julian Wolfson, Vittorio Addona & Robert Schmicker
Journal of Quantitative Analysis in Sports, July 2011
Abstract:
National Football League (NFL) teams spend substantial time and money trying to predict which college quarterbacks eligible to be drafted into the NFL will have successful professional careers. But despite this investment of resources, it is common for quarterbacks to perform much better or worse than anticipated. Prior work on this "quarterback prediction problem" has concluded that NFL teams are poor at determining which quarterbacks are likely to be successful based on information available prior to the draft. However, these analyses have generally focused only on quarterbacks who played in the NFL, ignoring those who were drafted but did not appear in a professional game. Using data on all quarterbacks drafted since 1997, we considered the problem of predicting NFL success as defined by two metrics (games played and Net Points), based on when a quarterback was drafted and his performances in college and at the NFL Combine. Our analyses suggest that college and combine statistics have little value for predicting whether a quarterback will be successful in the NFL. Contrary to previous work, we conclude that NFL teams aggregate pre-draft information-including qualitative observations-quite effectively, and their inability to consistently identify college quarterbacks who will excel in the professional ranks is a consequence of random variability in future performance due to factors which are unlikely to be observable.
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Digit ratios and preferences for aggressive content in entertainment
HaengRyang Huh
Personality and Individual Differences, September 2011, Pages 451-453
Abstract:
Digit ratios (2D:4D) contain information concerning an individual's propensity towards aggression. Our study adds the first clue to better understanding the relationship between 2D:4D and exposure to aggressive contents in entertainment products. Our findings suggest that individuals with low 2D:4D prefer aggressive contents such as action films, sports telecast, killing and achieving games, hip-hop music, and erotic video clips rather than do individuals with high 2D:4D. Also individuals with low 2D:4D tend to demonstrate less preference for romance films than individuals with high 2D:4D. In addition, we found that low 2D:4D was associated with a preference for sports instead of other genres of entertainment products. Therefore, 2D:4D (a putative correlate of prenatal sex steroids) helps us to better understand the rationale of individuals' preferences for media violence.
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Joel Potter
Journal of Quantitative Analysis in Sports, July 2011
Abstract:
Using a unique dataset, this paper empirically tests the Peltzman effect by investigating the behavior of Formula One racecar drivers. Estimates suggest that drivers become more reckless as their cars become safer, ceteris paribus. From 1963-1973, safety changes, on average, are estimated to leave the number of driver casualties unchanged. Furthermore, this is the first attempt to estimate specifically how drivers respond to changes in the conditional probability of fatality given an accident. Results provide evidence that the behavioral response of drivers is larger when the analysis is confined to changes in the conditional probability of a fatality given an accident.
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Interactive gaming reduces experimental pain with or without a head mounted display
Nakia Gordon et al.
Computers in Human Behavior, November 2011, Pages 2123-2128
Abstract:
While virtual reality environments have been shown to reduce pain, the precise mechanism that produces the pain attenuating effect has not been established. It has been suggested that it may be the ability to command attentional resources with the use of head mounted displays (HMDs) or the interactivity of the environment. Two experiments compared participants' pain ratings to high and low levels of electrical stimulation while engaging in interactive gaming with an HMD. In the first, gaming with the HMD was compared to a positive emotion induction condition; and in the second experiment the HMD was compared to a condition in which the game was projected onto a wall. Interactive gaming significantly reduced numerical ratings of painful stimuli when compared to the baseline and affect condition. However, when the two gaming conditions were directly compared, they equally reduced participants' pain ratings. These data are consistent with past research showing that interactive gaming can attenuate experimentally induced pain and its effects are comparable whether presented in a head mounted display or projected on a wall.
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Why do professional athletes have different time preferences than non-athletes?
Alex Krumer, Tal Shavit & Mosi Rosenboim
Judgment and Decision Making, August 2011, Pages 542-551
Abstract:
The objective of this paper is to measure and compare the subjective time discounting of professional athletes and non-athletes. By using a questionnaire, we found higher subjective discounting for professional athletes than for non-athletes. We also found that the professional athletes' win-orientation positively affected their present preferences. On the other hand, professional athletes' play-orientation, which reflects their attitude towards the game itself, negatively affected their present preferences. No such effects were found in non-athletes. We argue that the "win-at-all-costs" competitive approach that leads athletes to sacrifice everything in order to win may cause (or reflect) their higher preference for the present.
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Are NFL Coaches Risk and Loss Averse? Evidence from Their Use of Kickoff Strategies
John Urschel & Jun Zhuang
Journal of Quantitative Analysis in Sports, July 2011
Abstract:
Quantitative analysis of football play calling suggests that NFL coaches do not choose their strategies optimally. They tend to be overly cautious. One possible explanation for this finding is that NFL coaches are averse to risk and loss. We propose a prospect theory based model of coaches' utility and estimate the model's parameters using kickoff data from the 2009 NFL season. Using an outcome measure of points scored on the initial post-kickoff possession we analyze two strategic kickoff decisions that involve risk-reward tradeoffs: the decision to kick a surprise onside kickoff or a regular kickoff, and the decision to accept a touchback or run the ball out of the endzone. Surprise onside kickoffs may yield a more favorable mean points scored value for the kicking team than a regular kickoff, yet surprise onside kickoffs are infrequently used (and thus the same size is small and the p-value of significance test is 0.68). Coaches appear averse to the possible loss involved in the surprise onside kickoff. Running the ball out yields a higher mean points scored for the receiving team than accepting a touchback, but it entails some risk (fumbles are lost in 2 percent of returns). Nevertheless, declining the touchback option and running the ball out is very common. Coaches do not appear excessively risk averse when presented with this choice over possible gains. Prospect theory models allow for risk aversion over possible gains, as in traditional expected utility theory, and in addition they permit an asymmetric aversion to losses. A prospect theory model therefore seems suitable for our analysis of kickoff strategies. We estimate a risk aversion coefficient value of 0.66 and a loss aversion coefficient value of 1.55, where values <1 and>1 indicate risk and loss aversion, respectively. Our analysis supports the notion that NFL coaches are both modestly risk averse and loss averse. In other words, coaches display diminishing sensitivity to changes in scoring outcomes as they move further from a reference point (zero), and for scoring gains and losses of equal magnitude they suffer more from a loss than they enjoy from a gain. This result may explain their propensity for making conservative strategic choices that, at first glance, appear sub-optimal.
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The Carryover Effect Does Not Influence Football Results
Dries Goossens & Frits Spieksma
Journal of Sports Economics, forthcoming
Abstract:
In a round robin tournament, it is often believed that each team has an effect on its opponent, which carries over to the next game of that opponent. Indeed, if team A plays against team B, and subsequently against team C, A's performance against C may have been affected by B, and we say that team C receives a carryover effect from B. For instance, if team B is a very strong team, then team A could be exhausted and discouraged after this game, which could benefit its next opponent, team C. Clearly, any schedule will lead to carryover effects. In practice, the perceived influence of carryover effects has been used as an argument when producing a schedule. In this work, we develop an approach to measure whether carryover effects have an influence on the outcome of football matches. The authors apply this method on the highest division in Belgium, using data from over 30 seasons, amounting over 10,000 matches. In our data set, we find no evidence to support the claim that carryover effects affect the results, which has major implications for the sporting community with respect to generating fixtures.
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The value of life: Real risks and safety-related productivity in the Himalaya
Jeremy Goucher & William Horrace
Labour Economics, forthcoming
Abstract:
This paper estimates the value of a statistical life from commercial Himalayan expeditions. Because deaths occur with a fair amount of regularity, fatality rates are calculated for each mountain trail and are, hence, disaggregated measures of risk. Also, since the marginal product of labor in the industry is (in part) the marginal product of safety, our revenue measures may account for unobserved safety-related productivity of guides. Guide safety is explicitly observed by market participants, and is reflected in higher wages for safer guides. Our VSL estimates are about $5 M.
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On Estimating the Ability of NBA Players
Paul Fearnhead & Benjamin Matthew Taylor
Journal of Quantitative Analysis in Sports, July 2011
Abstract:
This paper introduces a new model and methodology for estimating the ability of NBA players. The main idea is to directly measure how good a player is by comparing how their team performs when they are on the court as opposed to when they are off it. This is achieved in such a way as to control for the changing abilities of the other players on court at different times during a match. The new method uses multiple seasons' data in a structured way to estimate player ability in an isolated season, measuring separately defensive and offensive merit as well as combining these to give an overall rating. The use of game statistics in predicting player ability will be considered. Results using data from the 2008/9 season suggest that LeBron James, who won the NBA MVP award, was the best overall player. The best defensive player was Lamar Odom and the best rookie was Russell Westbrook, neither of whom won an NBA award that season. The results further indicate that whilst the frequently-reported game statistics provide some information on offensive ability, they do not perform well in the prediction of defensive ability.
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Productivity and New Audiences: Empirical Evidence From Professional Basketball
Christian Deutscher
Journal of Sports Economics, June 2011, Pages 391-403
Abstract:
Changing clubs in professional sports lets a player face a new supportive crowd during home games, hence the question arises how performance is impacted by changing teams. This article measures the impact of the changed audience on free throw shooting performance. The data set includes all free throw attempts for 10 seasons from the National Basketball Association (NBA) and distinguishes between home and away games. Results support the idea that only free agents who were able to select a new team worsened their performance due to social pressure experienced during home games, while the performance during away games is unaffected. They suggest that especially bad free throw shooters suffer from facing this additional pressure.