Number of players who gain ball possession as a function of basketball mass among 9-11-year-old male players

This study analyzed whether a ball with a higher (540-g) or lower (440-g) mass than the regulation ball (485-g) resulted in a larger number of participants gaining ball possession during games. Prior studies have indicated that ball handling is facilitated by decreasing the mass of the ball. It was assumed that a greater number of children gaining possession of the ball indicated greater ease of use and more control. Thus, the hypothesis was that the number of participants who gained ball possession would increase when using a ball of lower mass. The participants were 54 boys from six youth basketball teams. Participants played four games with each one of the three different balls and the number of possessions was calculated using videos of each game. The hypothesis was only partially supported: the number of participants who gained possession with the regular ball was similar to that with the 440-g ball and with the 540-g ball, but a greater number of participants gained possession with the 440-g ball in comparison to the 540-g ball. This result suggests balls that differ by more than 65 g may affect actual game outcomes.     

Visual Exploration When Surrounded by Affordances: Frequency of Head Movements Is Predictive of Response Speed

Little is known about the actions supporting exploration and their relation to subsequent actions in situations when participants are surrounded by opportunities for action. Here, the movements that support visual exploration were related to performance in an enveloping football (soccer) passing task. Head movements of experienced football players were quantified with inertial measurement units. In a simulated football scenario, participants completed a receiving–passing task that required them to indicate pass direction to one of four surrounding targets, as quickly as they could after they gained simulated ball possession. The frequency of head movements before and after gaining ball possession and the pass response times were recorded. We controlled exploration time—the time before gaining simulated ball possession—to be 1, 2, or 3?seconds. Exploration time significantly influenced the frequency of head movements, and a higher frequency of head turns before gaining ball possession resulted in faster pass responses. Exploratory action influenced subsequent performatory action. That is, higher frequencies of head movements resulted in faster decisions. Implications for research and practice are discussed.     

Possession is not always the law: With age, preschoolers increasingly use verbal information to identify who owns what

Children can identify owners either by seeing a person in possession of an object (a visual cue) and inferring that they are the owner or by hearing testimony about a claim of ownership (a verbal cue). A total of 391 children between 2.5 and 6years of age were tested in three experiments assessing how children identify owners when these two cues are in conflict. Children were presented with stories using two dolls and a toy. One doll possessed the toy, and children were told that the toy was either the possessor's or the nonpossessor's. Two forms of ownership statement were used: a third-person statement, "That is Billy's ball", and a first-person statement by one of the dolls, "That is my ball". The results show that by 4years of age, children prioritize the verbal statements as a more reliable cue to ownership than physical possession. Younger children did not prioritize possession over the verbal cue to ownership but rather gave mixed responses. These results are discussed in terms of children's social experience outside of the home and their acceptance of testimony in other domains.     

Effects of public posting,goal setting,and oral feedback on the skills of female soccer players

We evaluated the effects of public posting, goal setting, and oral feedback on the skills of 3 female high school soccer players during practice scrimmages. The dependent variables were the percentage of appropriate responses when the player (a) kept and maintained possession of the ball, (b) moved to an open position during a game restart (e.g., goal or corner kick), and (c) moved to an open position after passing the ball. We also assessed the extent to which changes in practice performances generalized to games. A social validity questionnaire was completed by both players and coaches to assess the acceptability of the intervention's goals, procedures, and outcomes. Results indicate that the intervention was effective in improving performances during practice scrimmages but produced limited generalization to game settings.     

Visual target detection is impaired at event boundaries

Boundaries between meaningful events are key moments in comprehending human action. At these points, viewers may focus on the event's contents at the expense of other information. We tested whether visual detection was impaired at those moments perceivers judged to be boundaries between events. Short animated football clips were used as stimulus material, and event boundaries were imposed by having the ball change possession. In a first experiment, we found that possession changes were perceived to be event boundaries. In a second experiment, participants were asked to keep track of 4 of 10 players and to watch for 120 ms probes appearing either at an event boundary or a nonboundary. Probe detection was less accurate at event boundaries. This result suggests that the segmentation of ongoing activity into events corresponds with the regulation of attention over time.     

儿童基于不同线索的所有权判断及其文化差异

对所有权的认知依赖于不同的线索。儿童很早就能通过不同的线索判断所有权。3岁幼儿能够基于先占、劳动、证言、许可控制、刻板印象等线索判断所有权。社会经济和文化因素会影响幼儿对所有权线索的利用, 如社会经济发展不发达地区儿童对先占线索的利用在发展上会有所延迟, 集体主义文化中的幼儿在进行所有权判断时更保守一些, 表现为当先占线索和劳动线索冲突时更倾向于判断物品属于先占者。未来研究应重视通过冲突线索范式探索不同线索在儿童所有权判断中的权重, 探索儿童基于不同线索判断所有权背后的内部心理机制, 同时尝试利用眼动技术等手段对2岁以下幼儿的所有权认知进行研究。     

Abdominal exercise intensities on firm and compliant surfaces

Muscle activities at 15 sites were compared within a group of healthy young adults to evaluate their relative intensities during six abdominal exercises: partial and full sit-ups on a firm surface (floor) and on an exercise ball that was either stabilized or unstabilized. The most strenuous abdominal exercise overall (i.e., whole body workout) was the full sit-up on a firm surface which included significant muscle activities in the lower extremities. Exercise intensity was also high in the full and partial sit-ups when performed on a ball. The partial sit-up on the floor was the least strenuous of the six exercises. The greatest effect on the abdominal muscles was observed in the partial sit-up on a ball (stabilized and unstabilized). Results suggest that, although abdominal exercises on a ball may be gentler on the hip and lower back, overall exercise intensity is not necessarily lower than that on the floor. Moreover, partial sit-ups, both on the floor and on a ball, also required greater neck muscle activities than full sit-ups. In deciding what type of sit-up to do, exercise surface and different muscular activities between the partial and full sit-ups should be considered.     

Rationalization,Evidence, and Pretense

In this paper I distinguish the category of “rationalization” from various forms of epistemic irrationality. I maintain that only if we model rationalizers as pretenders can we make sense of the rationalizer's distinctive relationship to the evidence in her possession. I contrast the cognitive attitude of the rationalizer with that of believers whose relationship to the evidence I describe as “waffling” or “intransigent”. In the final section of the paper, I compare the rationalizer to the Frankfurtian bullshitter.     

Partial Understanding and Concept Possession: A Dilemma

In the light of partial (mis)understanding, we examine the thesis that concepts are individuated in terms of possession conditions and show that adherents face a fatal dilemma: Either concept‐individuating possession conditions include cases of partially (mis)understood concepts or not. If yes, possession conditions do not individuate concepts. If no, the thesis is too restricted and lacks a minimally satisfactory level of generalization.     

Set similarity modulates object tracking in dynamic environments

Based on the observation that sports teams rely on colored jerseys to define group membership, we examined how grouping by similarity affected observers’ abilities to track a “ball” target passed between 20 colored circle “players” divided into two color “teams” of 10 players each, or five color teams of four players each. Observers were more accurate and exerted less effort (indexed by pupil diameter) when their task was to count the number of times any player gained possession of the ball versus when they had to count only the possessions by a given color team, especially when counting the possessions of one team when players were grouped into fewer teams of more individual members each. Overall, results confirm previous reports of costs for segregating a larger set into smaller subsets and suggest that grouping by similarity facilitates processing at the set level.     

Behavioral momentum in college basketball

Three classes of events were scored from videotapes of 14 college basketball games during the 1989 National Collegiate Athletic Association tournament: reinforcers (such as points and favorable turnovers), adversities (such as missed shots, unfavorable turnovers, and fouls), and responses to adversities (favorable or unfavorable outcomes of the first possession of the ball following an adversity). Within-game and within-team analyses of these data supported three findings. First, a team's favorable response to an adversity generally increased as the rate of reinforcement increased 3 min preceding the adversity. Second, basketball coaches called time-out from play when being outscored by their opponents an average of 2.63 to 1.0. Third, calling time-outs from play appeared to be an effective intervention for reducing an opponent's rate of reinforcement. Rates of reinforcement during the 3 min immediately after a time-out were nearly equal for both teams. Results are discussed within a behavioral momentum framework.     

Motion by nearby players biases perception but not action in judgments of baseball destination

In this research, the influence of irrelevant reference frames on estimates of ball destination was examined. In 3 experiments, confederate base runners and fielders served as distractor stimuli while balls were rolled from home plate to random locations along a barrier hidden under an elevated tarp between first and second base. Stationary participants estimated the position that the ball would exit from under the tarp if there were no barrier, whereas running participants ran along the back edge of the barrier and touched the top of the tarp above where they believed the ball would exit. Estimates of ball destination were significantly biased in the direction opposite to the confederates' motion for stationary participants, but were accurate for running participants. These findings are consistent with other perception-action dissociations, and show that relative motion effects can occur in a naturalistic setting.     

Aiming at a far target under different viewing conditions: visual control in basketball jump shooting

Most research on visual search in aiming at far targets assumes preprogrammed motor control implying that relevant visual information is detected prior to the final shooting or throwing movements. Eye movement data indirectly support this claim for stationary tasks. Using the basketball jump shot as experimental task we investigated whether in dynamic tasks in which the target can be seen until ball release, continuous, instead of preprogrammed, motor control is possible. We tested this with the temporal occlusion paradigm: 10 expert shooters took shots under four viewing conditions, namely, no vision, full vision, early vision (vision occluded during the final +/-350 ms before ball release), and late vision (vision occluded until these final +/-350 ms). Late-vision shooting appeared to be as good as shooting with full vision while early-vision performance was severely impaired. The results imply that the final shooting movements were controlled by continuous detection and use of visual information until ball release. The data further suggest that visual and movement control of aiming at a far target develop in close correspondence with the style of execution.     

Children and Adults Use Gender and Age Stereotypes in Ownership Judgments

In everyday life, we are often faced with the problem of judging who owns an object. The current experiments show that children and adults base ownership judgments on group stereotypes, which relate kinds of people to kinds of objects. Moreover, the experiments show that reliance on stereotypes can override another means by which people make ownership judgments—inferring ownership from first possession. Experiment 1 replicates previous findings in showing that children and adults are strongly biased to assume that the first person to possess an object is its owner, while also demonstrating that the first-possession bias shows specificity to ownership. Experiment 2 shows that preschoolers and adults used gender stereotypes to make ownership judgments, and they do this even when stereotypes conflict with first possession. Experiment 3 reports similar findings but with age stereotypes. These findings reveal that stereotypes are a powerful means for making ownership judgments.     

Forecasting outcomes of the World Cup 2006 in football: Performance and confidence of bettors and laypeople

ObjectivesMotivated by a paucity of research on sports forecasting, this paper examines how well individuals with varying degrees of relevant knowledge predict football (soccer) and how much confidence they have in their predictions.Design and procedureThree groups of participants (110 art students, 81 sports students, and 85 bettors) representing three levels of knowledge (poor, moderate, and expert) performed five forecasting tasks with relation to the outcome of the first round of the World Cup 2006. The tasks were assumed to reflect different degrees of complexity. About half of the participants obtained relevant information (world rankings). The participants stated their confidence in connection to conducting those tasks.ResultsWhereas the groups had roughly similar levels of performance in three tasks (i.e., predicting the teams qualifying for the second round as well as two types of match statistics), the knowledgeable and expert participants were better at predicting scores and percentage of ball possession in the matches than the naïve participants. Relatively few participants performed better than the simple rule that followed world rankings. Regardless of task complexity, the knowledgeable and expert participants were found to be significantly more confident about their forecasts than the naïve participants. Access to information had limited influence on forecasting performance and confidence.ConclusionThe present study shows that the forecasting performance of football experts and laypeople varies dependent on task. For easy tasks, they tend to predict equally well, partly because laypeople might use well-adapted heuristics. Once the prediction tasks become more difficult, the experts may take advantage of their domain-specific skills and produce forecasts that excel those of the laypeople.     

Two-year-olds' search strategies and visual tracking in a hidden displacement task

Children younger than 3 years have difficulty with search tasks that involve hidden displacement. Partial visual information was provided about a ball's path as it moved toward a hiding place. Children (2.0 and 2.5 years old) saw a ball rolling down a ramp placed behind a transparent screen with 4 opaque doors. A wall, placed on the ramp and directly behind 1 of the doors, protruded above the screen and stopped the ball. Children were asked to find the ball. The transparency of the screen permitted visual tracking of the ball between the doors, but its final resting place was obscured. Both age groups were equally proficient at tracking the ball as it rolled behind the screen, but the 2.5-year-olds were more likely to reach to the correct door. Looking behavior was related to errors in the younger group in that tracking that stopped short or continued past the correct door was associated with incorrect choices.     

Anchoring,Familiarity, and Confidence in the Detection of Deception

Anchoring in judgments is the tendency for the final judgment to be biased toward the initial estimate through insufficient adjustment. In the context of the detection of deception, it has been used to explain phenomena such as negative absolute leakage and the truthfulness bias. We examined the influence of order of judgment type on attitude ratings, accuracy, and the truthfulness bias. Receivers of communications should tend to anchor their judgments on the sender's attitudinal position if asked to make attitude judgments first and on the sender's behavior if asked to make truthfulness judgments first. The results partly support these predictions. Negative absolute leakage, accuracy, and the truthfulness bias were not significantly different for those who made attitude judgments before truthfulness judgments. However, results show that accuracy decreased as the session continued and there was no difference in the confidence with which truth and deception judgments were made, but there was a positive relation between confidence and truthfulness bias.     

Self-Talk in the Swimming Pool: The Effects of Self-Talk on Thought Content and Performance on Water-Polo Tasks

The present study examined the effect of instructional and motivational self-talk on the occurrence of interfering thoughts and performance on two water-polo tasks with similar characteristics performed in the same environment. Two experiments were conducted in the swimming pool, one involving a precision task (throwing a ball at target) and one involving a power task (throwing a ball for distance). In the first experiment (precision task), both self-talk groups improved their performance in comparison to the baseline measure, with participants using instructional self-talk improving more. In the second experiment (power task), only the motivational self-talk group improved its performance significantly. In both experiments the occurrence of interfering thoughts declined for both groups. The results of the study provide further support for the effectiveness of self-talk and give preliminary evidence regarding likely mechanisms through which self-talk influence performance, that is through indications that self-talk reduces thoughts not related to task execution, thus enhancing concentration to the task.     

Performance and ease influence perceived speed

According to the action-specific perception account, perception is a function of optical information and the perceiver's ability to perform the intended action. While most of the evidence for the action-specific perception account is on spatial perception, in the current experiments we examined similar effects in the perception of speed. Tennis players reproduced the time the ball traveled from the feeder machine to when they hit it. The players judged the ball to be moving faster on trials when they hit the ball out-of-bounds than on trials where they successfully hit the ball in-bounds. Follow-up experiments in the laboratory showed that participants judged virtual balls to be moving slower when they played with a bigger paddle in a modified version of Pong. These studies suggest that performance and task ease influence perceived speed.     

Possession and Medicine in South Central India

Possession is a powerful and surprisingly prevalent belief system in many parts of the developing world. In India it is common for many reasons—isolation, illiteracy, polyglotism, lack of an adequate medical infrastructure, a need for hope. Possession, and the practice of exorcism, is more than just an explanatory system based on superstition and folk lore. It is also an important social structure and force that allows the integration of the sick into the community of the well, and facilitates a first albeit tentative step from the local community to the medical community. In many parts of India, health care delivery as well as social organization is through the practice of possession. Thus, the role and power of possession needs to be appreciated if one seeks to affect health care delivery in India, and further possession should be appreciated if one seeks to better understand how some of its forces might in fact be curative.