Further analysis of the matching law to describe two- and three-point shot allocation by professional basketball players

The matching law was used to analyze whether the proportion of shots taken from two- or three-point range would match the proportional reinforcement rates produced by those shots when the reinforcement rate of three-point shooting was changed. Rule changes in 1994 and 1997 altered the distance of the three-point line in the National Basketball Association, which created a quasiexperimental reversal design, thereby naturally changing three-point reinforcement rates. The present data partially confirmed predictions made by the matching law, in that increases in the relative rate of three-point shots attempted corresponded to increases in the relative rate of three-point shots made.     

Basketball jump shooting is controlled online by vision

An experiment was conducted to examine whether basketball jump shooting relies on online visual (i.e., dorsal stream-mediated) control rather than motor preprogramming. Seventeen expert basketball players (eight males and nine females) performed jump shots under normal vision and in three conditions in which movement initiation was delayed by zero, one, or two seconds relative to viewing the basket. Shots were evaluated in terms of both outcome and execution measures. Even though most shots still landed near the basket in the absence of vision, end-point accuracy was significantly better under normal visual conditions than under the delay conditions, where players tended to undershoot the basket. In addition, an overall decrease of inter-joint coordination strength and stability was found as a function of visual condition. Although these results do not exclude a role of motor preprogramming, they demonstrate that visual sensory information plays an important role in the continuous guidance of the basketball jump shot.     

Social Role Theory and the Perceived Gender Role Orientation of Athletes

In this research we examined the influence of athletic roles upon the perceived gender role orientations of male and female athletes. Participants were 148 students who read a bogus newspaper article that described either a male or female athlete who had successfully competed in an athletic event. The type of sport (football, basketball, and cheerleading) was manipulated. Female football players and basketball players were perceived as higher in agency than female cheerleaders. Male cheerleaders were perceived as higher in communality than male football players and male basketball players. Participants made external attributions concerning the motivations of athletes who competed in gender traditional sports. They made internal attributions concerning the motivations of athletes who competed in gender nontraditional sports. These findings are examined in relation to social role theory.     

An especial skill: Support for a learned parameters hypothesis

We tested the ‘learned parameters’ hypothesis as an explanation of the ‘especial skill effect’. Outcome attainment and movement kinematics were recorded for 10 expert and 10 novice players performing basketball free-throw shots at five distances (11-19 ft) with a regular and heavy weight basketball. As predicted, experts performed better than expected relative to the regression equation at the 15 ft, free-throw line with the regular basketball, supporting the ‘especial skill effect’. This effect was not present for the experts when shooting with the heavy ball. Novices did not show an advantage at the free-throw line when performing with either ball. Although the outcome attainment scores support the ‘learned parameters’ hypotheses, kinematic analysis failed to identify differences in the movement pattern for the especial skill, suggesting that these skills (i.e., shooting at different distances) are not governed by separate motor programs.     

The generalist bias

This research introduces the generalist bias – a tendency to reward and select people with general skills when complementary, specialized skills are needed. Five studies investigated its effects. Study 1 confirmed the existence of the bias in a context-free experiment. Study 2 showed that the compensation of players in NBA teams was related to their two- rather than their three-point scoring. Study 3 showed that basketball fans favored all-around players even when three-point shooters would better complement a team’s needs. Study 4 showed that the generalist bias occurred in HR recruiting, and Study 5 showed that companies often recruited specialists to handle multiple, unrelated jobs. In addition, studies 3 and 4 also showed that joint evaluations (comparing specialists and generalists side-by-side) strengthened the generalist bias, whereas separate evaluations weakened it.     

Zebrafish choice behavior is sensitive to reinforcer rate,immediacy, and magnitude ratios

Behavioral flexibility has, in part, been defined by choice behavior changing as a function of changes in reinforcer payoffs. We examined whether the generalized matching law quantitatively described changes in choice behavior in zebrafish when relative reinforcer rates, delays/immediacy, and magnitudes changed between two alternatives across conditions. Choice was sensitive to each of the three reinforcer properties. Sensitivity estimates to changes in relative reinforcer rates were greater when 2 variable-interval schedules were arranged independently between alternatives (Experiment 1a) than when a single schedule pseudorandomly arranged reinforcers between alternatives (Experiment 1b). Sensitivity estimates for changes in relative reinforcer immediacy (Experiment 2) and magnitude (Experiment 3) were similar but lower than estimates for reinforcer rates. These differences in sensitivity estimates are consistent with studies examining other species, suggesting flexibility in zebrafish choice behavior in the face of changes in payoff as described by the generalized matching law.     

An especial skill in elite wheelchair basketball players

We aimed to investigate whether an especial skill is present in elite wheelchair basketball players when taking twenty shots with a regular basketball from five different distances (11 ft, 13 ft, 17 ft, & 19 ft) from the basket including the free throw line (15 ft). Twelve elite male basketball players participated. The results showed that as distance increased shot accuracy decreased in line with force by variability predictions for the 11 ft, 13 ft, 17 ft, & 19 ft distances. However, shot performance at the free throw line where players are more familiar with practicing free throw shots did not follow this trend. A linear regression line was drawn to predict performance at the free throw line based on nearer (11 ft & 13 ft) and farer (17 ft & 19 ft) distances to the basket, this was then compared to actual performance. A significant difference between actual and predicted scores was found (p < .05) supporting the presence of an especial skill. Significant positive correlations were found for the 11 ft and 17 ft distance, age, years of playing, and accumulated practice hours with performance at the 15 ft line (p < .05). These correlations imply the operation of generalization in the especial skill. This observation received support from applying a model in which shot accuracy as a function of distance was approximated by two regression lines.     

Representative design: Does the addition of a defender change the execution of a basketball shot?

ObjectiveThe aim of this study was to examine the influence of a defender on the performance of a motor skill from an invasion sport.DesignHighly skilled basketball players performed different variations of basketball shots using a randomised test schedule.MethodParticipants completed a total of 30 test trials comprising 6 trials of 5 different shot types in both defended and undefended conditions.ResultsThe presence of a defender led to significant changes in several behavioral measures including faster shot execution times, longer jump times, and an increase in the amount of time that the ball spent in the air as it travelled to the basket after being released from the shooter's hand. These behavioral changes were accompanied by an overall decline in shooting accuracy of over 20%. Defended shots also tended to elicit greater amounts of movement variability which, when interpreted in conjunction with the other findings, suggests that participants were attempting to adapt their movements to accommodate for the changing demands of the performance environment. Comparisons across different shot types revealed that the influence of the defender was generally context and task dependent.ConclusionsThe results have important implications for representative task design, and highlight how the manipulation of key information sources can have a marked effect upon behavioral responses.     

The experience of ego threat in the public arena: A study of air ball shots performance in collegiate basketball

Performance following ego threat has often been studied in the laboratory under conditions, which may limit external validity. In the current investigation, Men’s college basketball games were studied focusing on attempts at shot that completely missed the basket and are thus known colloquially as “air ball” shots (ABS). When an away player launches an ABS, the home crowd is likely to recite in unison an “air ball, air ball” chant (ABC) to single him out for a uniquely subpar performance. Similar poor performance by a home player is almost always ignored. An archival exploration showed that away players who shot an ABS had a lower success rate in the shot immediately after, as compared to home players launching an ABS, however, this difference was unrelated to ABC. Also, players with a better shooting ability were better able to deal with the debilitating effects. The results expand ego threat research and are discussed in the context of ego‐depletion and a model is proposed to predict performance quality in social context when the negative feedback is delivered by partisans and one’s knowledge of his skill level is known.     

Response selection and execution skills of professionals and novices during singles tennis competition.

This study extended research on sport expertise concerning the development of cognitive and motor skills in singles tennis (McPherson, 1999). 12 adult male professional and novice tennis players were videotaped during singles competition. Opponents for matches were randomly selected within each group of participants. Two tennis experts utilized an observational scale to judge players' performance generated during competition for serves and shots following the serve, e.g.. return of serves, lobs. Each player was scored on three performance components: quality of movement to or control of the ball for serves or shots attempted (control skills), appropriateness of serve or shot selections in the context of game situations (response selection skills), and quality of serves or shots produced (response execution skills). Relative frequency scores for the highest category of each performance component were derived according to the number of opportunities to respond. Serve performance indicated both groups were able to control their serves: however, professionals made more tactical selections and forceful executions. Shot performance indicated professionals made more successful movement to and control of shots, tactical shot selections, and forcing shot executions than novices. Overall, players' tactical response selections were greater than their forceful response executions. Thus, assessing players' decisions during competition may provide vital information concerning tactical skill development. Further, professional players exhibited higher and more consistent tactical behavior than elite collegiate players examined in 1999 by McPherson. Findings were attributed to tactical knowledge and motor skill development resulting from competition and practice experiences.     

运动技能水平与躯体感觉输入对运动表象的影响

运动表象质量与运动技能水平有关,运动表象质量随着运动技能水平的提高而上升。器械使用可使人脑产生可塑性改变,使用者会将器械纳入身体图式。然而,两者影响运动表象的神经心理机制还不清楚。本研究采用功能性磁共振成像探析篮球运动员与新手在不同持球条件下表象投篮时脑功能活动的差异。结果表明运动员表象质量较好,镜像神经系统激活高于新手;持球条件下运动员表象质量显著高于不持球条件下,镜像神经系统激活程度显著低于不持球条件下。研究说明持器械可以显著提高运动员的表象质量,器械使用带来镜像神经系统的可塑性变化。     

Delayed matching-to-sample performance: Effects of relative reinforcer frequency and of signaled versus unsignaled reinforcer magnitudes

Six pigeons were trained on a delayed red-green matching-to-sample task that arranged four delays within sessions. Matching responses intermittently produced either 1.5-s access to food or 4.5-s access to food, and nonmatching responses produced either 1.5-s or 4.5-s blackout. Two phases were conducted: a signaled phase in which the reinforcer magnitudes (small and large) were signaled by houselights (positioned either on the left or right of the chamber), and an unsignaled phase in which there was no correlation between reinforcer magnitude and houselight position. In both phases, the relative frequency with which red and green matching responses produced food was varied across five values. Both matching accuracy and the sensitivity of performance to the distribution of reinforcers for matching responses decreased with increasing delays in both phases. In addition, accuracy and reinforcer sensitivity were significantly lower on signaled small-reinforcer trials compared with accuracy and sensitivity values on signaled large-reinforcer trials and on both types of unsignaled trials. These results are discussed in the context of research on both nonhuman animal and human memory.     

Concurrent reinforcement schedules for problem behavior and appropriate behavior: experimental applications of the matching law

This study evaluated how children who exhibited functionally equivalent problem and appropriate behavior allocate responding to experimentally arranged reinforcer rates. Relative reinforcer rates were arranged on concurrent variable-interval schedules and effects on relative response rates were interpreted using the generalized matching equation. Results showed that relative rates of responding approximated relative rates of reinforcement. Finally, interventions for problem behavior were evaluated and differential reinforcement of alternative behavior and extinction procedures were implemented to increase appropriate behavior and decrease problem behavior. Practical considerations for the application of the generalized matching equation specific to severe problem behavior are discussed, including difficulties associated with defining a reinforced response, and obtaining steady state responding in clinical settings.     

Moral growth among athletes and nonathletes: a comparative analysis

Sport may be described as a unique moral context encouraging adaptations in participants' moral reasoning. The relation between sport participation and maturity of moral reasoning regarding general social problems and sport-specific dilemmas was investigated in two related studies. Study 1 involved 100 high school and college basketball players and nonathletes, with an equal distribution of females and males. Moral protocols were administered and scored according to Haan's (1978, 1983) interactional model of moral development. Multivariate analyses of variance revealed no moral reasoning differences between high school basketball players and nonathletes, but high school females' moral reasoning was more mature than was males'. Within the college sample, nonathletes' moral reasoning was significantly more mature than was athletes'. Also, females' moral reasoning about sport was more mature than that of their male counterparts, though no sex differences were found in general life moral reasoning. In Study 2, 20 swimmers were added to the college sample. Basketball players employed less mature moral reasoning about sport than both swimmers and nonathletes (who did not differ from each other). Results were discussed in terms of sport-specific experiences.     

The affective costs of overconfidence

Positive illusions, though often beneficial (Taylor & Brown, 1988 ), can diminish the pleasure of outcomes. This prediction follows from decision affect theory. We investigated this prediction by measuring the confidence that recreational basketball players felt while making shots and the pleasure they felt with subsequent outcomes. Results showed that most players were overconfident. Those who were more overconfident tended to experience less enjoyment with their outcomes. Using individual parameter estimates from decision affect theory, we estimated how each player would have felt if their self assessments had been accurate. For the vast majority, better calibration would have led to greater pleasure. In a second study, we randomly assigned players to a debiasing treatment condition or a control condition. Relative to the control players, debiased players were better calibrated and derived greater average pleasure from the task. Copyright © 2004 John Wiley & Sons, Ltd.     

Angular relationships regulate coordination tendencies of performers in attacker–defender dyads in team sports

This study examined the continuous interpersonal interactions of performers in dyadic systems in team sports, as a function of changing information constraints. As a task vehicle, we investigated how attackers attained success in 1v1 sub-phases of basketball by exploring angular relations with immediate opponents and the basket. We hypothesized that angular relations would convey information for the attackers to dribble past defenders. Four basketball players performed as an attacker and defender in 1v1 sub-phases of basketball, in which the co-positioning and orientation of participants relative to the basket was manipulated. After video recording performance behaviors, we digitized participant movement displacement trajectories and categorized trials as successful or unsuccessful (from the attackers’ viewpoint). Results revealed that, to successfully dribble past a defender, attackers tended to explore the left hand side of the space by defenders by increasing their angular velocity and decreasing their angular variability, especially in the center of the court. Interpersonal interactions and goal-achievement in attacker–defender dyads appear to have been constrained by the angular relations sustained between participants relative to the scoring target. Results revealed the functionality of exploratory behaviors of participants attempting re-align spatial relations with an opponent in 1v1 sub-phases of team games.     

Especial skills: their emergence with massive amounts of practice

Differing viewpoints concerning the specificity and generality of motor skill representations in memory were compared by contrasting versions of a skill having either extensive or minimal specific practice. In Experiments 1 and 2, skilled basketball players more accurately performed set shots at the foul line than would be predicted on the basis of the performance at the nearby locations, suggesting considerable specificity at this distance. This effect was replicated even when the lines on the court were obscured (in Experiment 2). However, the effect was absent when jump shots were executed in Experiment 3. The authors argue that massive levels of practice at 1 particular member of a class of actions produce specific effects that allow this skill to stand out from the other members of the class, giving it the status of an especial skill. Various theoretical views are proposed to account for the development of these skills.