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931.
PurposeThe mediating relationship of self-conceptions as a risky driver on self-reported driving violations was examined for players of “drive’em up” and “circuit” racing video games using an Internet survey of automobile and racing club members. Structural equation modelling (SEM) tested Fischer et al. (2012) extended socio-cognitive model on the effects of risk-glorifying media on cognitions and actions.MethodAn Internet questionnaire was developed and relied upon validated instruments or questions derived from previous surveys. Driver club members were asked about: (1) their frequency of video game playing, (2) self-perceptions as a risky driver and (3) self-reported driving violations. SEM was performed to examine mediating effects of racing video game playing on self-reported driving violations.ResultsPlaying “drive‘em up” video games positively predicted risky self-concept (β = .15, t = 2.26), which in turn, positively predicted driving violations (β = .73, t = 8.63), while playing “circuit racing” games did not predict risky self-concept, although risky self-concept did predict driving violations (β = .72, t = 8.67).ConclusionsSelf-concept as a risky driver mediated the relationship between racing video game playing and self-reported driving violations for “drive’em up”, but not for “circuit racing” video games. These findings are congruent with Fischer and colleagues’ experimental model that self-concept as a reckless driver mediated the relationship between racing video game playing for “drive’em up”, but not for “circuit racing” games and risk-taking behavior in a video of road traffic scenarios.  相似文献   
932.
The relationship between adolescent extra‐curricular activities and choice of graduate‐education field was examined among students from three fields of study, science (n = 12), art (n = 12), and education (n = 14), using qualitative and quantitative methods. Results of profile analysis indicated that the different majors participated in stereotypically varying activities when they were adolescents. Science majors generally participated in mathematics and science activities during adolescence. Art majors generally participated in theater and music activities, and education majors tended to have participated in social leadership and educational activities. Interviews with the participants supported these findings and provided a more comprehensive discussion of these tendencies. While in high school, the participants had many influences when determining a field of study. Using personal happiness as a guide, the participants chose activities and ultimately graduate‐level majors that reflected their interests. It was concluded that adolescent extra‐curricular activities are important in the development of interest in creatively talented individuals and may lead to graduate field selection.  相似文献   
933.
采用选择/无选范式,通过操纵任务呈现方式(估算题目的数字消失与否)与主次任务反应顺序(先反应算术任务或先反应字母任务),考察了双任务协调在算术策略选择与执行中的潜在作用。结果显示:(1)不同双任务呈现情境中个体的算术策略表现有明显区别。算术题目数字不消失相比消失时,个体对主、次任务的回答正确率都比较低,在策略选择上更倾向于选择较简单策略,在策略执行上准确性偏低;(2)双任务反应顺序会影响算术策略运用表现。先反应算术任务时,双任务情境只影响策略执行的准确性;而先反应字母任务时,双任务情境对策略执行的准确性和反应速度均发挥干扰作用,且估算题目的数字消失与否对策略选择准确性的影响更大,策略选择适应性之间的差异亦更加明显。上述发现对于深入理解双任务协调功能在策略运用中的作用机制具有重要意义。  相似文献   
934.
In intertemporal choice research, choice tasks (i.e., choosing between $80 today and $100 in a year) are often used to elicit a discount rate. The discount rate derived from a choice task, however, is largely restricted by the granularities and ranges of the questions asked. We examined this restriction in three popular discount rate measurements using simulations and experiments, and we propose an alternative procedure (Three‐option Adaptive Discount rate measure (ToAD)), which is capable of measuring a wide range of discount rates (from approximately .035% to 350 000% annual percentage rate) with high precision using 10 questions, in under a minute. ToAD can be easily implemented in online surveys (i.e., Qualtrics). Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
935.
Recently, there has been increased interest in decisions‐from‐experience (where decision makers learn from observing the outcomes of previous choices), which provide valuable insights into the learning and preference construction processes underlying many daily decisions. Several process models have been developed to capture these processes, and while such models often fit the data well, many assume that the decision maker is a vigilant observer, processing each outcome. In two studies, we provide a critical test of this assumption using eye tracking to record directed visual attention when participants choose repeatedly among two options, each time being shown the outcome for their chosen option and for the foregone option. Consistently, we find that the vigilance assumption is not supported, with decision makers often not attending to outcome information. Moreover, (in)attention to outcomes is predictable, with vigilance decreasing as more choices are made, and being greater for obtained than for foregone outcomes, and when options deliver only gains as opposed to losses or a mixture of gains and losses. Furthermore, we find that this variation in attentional allocation plays a central role in the apparent indecisiveness (inconsistency) in choice, with increased attention to foregone outcomes predicting switches to that option on the next choice. Together, these findings highlight the value of eye tracking in investigations of decisions‐from‐experience, providing novel insight into the cognitive processes underlying them. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
936.
George G. Brooks 《Zygon》1997,32(3):439-453
Evolution can be a "weasel word" unless circumscribed to mean only a morphological change over time. When this is done, the fact of what can be distinguished from the faith of how . I believe that evolution is purely a natural process, but recognizing that everyone creates his or her own God, I feel justified in giving the name God to that mysterious presence in every interaction that causes transformation, since this is what gives the universe its dynamism. I relate how this God concept informs my religious and ethical life and gives my life meaning and purpose.  相似文献   
937.
Identification of reinforcers for individuals with developmental disabilities is often based on the outcome of preference assessments in which participants make selections from among a variety of items. We determined the extent to which individuals might show a general preference for food items over leisure items during such assessments and whether leisure items that are “displaced” by food items might nevertheless function as reinforcers. Arrays consisting of food items only and then nonfood items only were presented separately to 14 participants and then were ranked to determine preference. The top selections from these initial assessments were subsequently combined in a third assessment, and preferences were again established. All but 2 participants showed a general preference for food items, such that selection of nonfood items in the combined arrays was displaced downward relative to selection of nonfoods in the nonfood-only arrays. Two of the participants were exposed to a condition in which a nonfood item was delivered contingent on the occurrence of an adaptive response, and increased rates of responding by both individuals were observed. Results are discussed in terms of limitations posed by using only food items as reinforcers and the resulting need to take precautionary measures when attempting to identify nonfood reinforcers.  相似文献   
938.
Five pigeons were trained in a concurrent foraging procedure in which reinforcers were occasionally available after fixed times in two discriminated patches. In Part 1 of the experiment, the fixed times summed to 10 s, and were individually varied between 1 and 9 s over five conditions, with the probability of a reinforcer being delivered at the fixed times always .5. In Part 2, both fixed times were 5 s, and the probabilities of food delivery were varied over conditions, always summing to 1.0. In Parts 3 and 4, one fixed time was kept constant (Part 3, 3 s; Part 4, 7 s) while the other fixed time was varied from 1 s to 15 s. Median residence times in both patches increased with increases in the food-arrival times in either patch, but increased considerably more strongly in the patch in which the arrival time was increased. However, when arrival times were very different in the two patches, residence time in the longer arrival-time patch often decreased. Patch residence also increased with increasing probability of reinforcement, but again tended to fall when one probability was much larger than the other. A detailed analysis of residence times showed that these comprised two distributions, one around a shorter mode that remained constant with changes in arrival times, and one around a longer mode that monotonically increased with increasing arrival time. The frequency of shorter residence times appeared to be controlled by the probability of, and arrival time of, reinforcers in the alternative patch. The frequency of longer residence times was controlled directly by the arrival time of reinforcers in a patch, but not by the probability of reinforcers in a patch. The environmental variables that control both staying in a patch and exiting from a patch need to be understood in the study both of timing processes and of foraging.  相似文献   
939.
An adjusting-amount procedure was used to measure discounting of reinforcer value by delay. Eight rats chose between a varying amount of immediate water and a fixed amount of water given after a delay. The amount of immediate water was systematically adjusted as a function of the rats' previous choices. This procedure was used to determine the indifference point at which each rat chose the immediate amount and the delayed amount with equal frequency. The amount of immediate water at this indifference point was used to estimate the value of the delayed amount of water. In Experiment 1, the effects of daily changes in the delay to the fixed reinforcer (100 microliters of water delivered after 0, 2, 4, 8, or 16 s) were tested. Under these conditions, the rats reached indifference points within the first 30 trials of each 60-trial session. In Experiment 2, the effects of water deprivation level on discounting of value by delay were assessed. Altering water deprivation level affected the speed of responding but did not affect delay discounting. In Experiment 3, the effects of varying the magnitude of the delayed water (100, 150, and 200 microliters) were tested. There was some tendency for the discounting function to be steeper for larger than for smaller reinforcers, although this difference did not reach statistical significance. In all three experiments, the obtained discount functions were well described by a hyperbolic function. These experiments demonstrate that the adjusting-amount procedure provides a useful tool for measuring the discounting of reinforcer value by delay.  相似文献   
940.
In a baseline condition, pigeons chose between an alternative that always provided food following a 30-s delay (100% reinforcement) and an alternative that provided food half of the time and blackout half of the time following 30-s delays (50% reinforcement). The different outcomes were signaled by different-colored keylights. On average, each alternative was chosen approximately equally often, replicating the finding of suboptimal choice in probabilistic reinforcement procedures. The efficacy of the delay stimuli (keylights) as conditioned reinforcers was assessed in other conditions by interposing a 5-s gap (keylights darkened) between the choice response and one or more of the delay stimuli. The strength of conditioned reinforcement was measured by the decrease in choice of an alternative when the alternative contained a gap. Preference for the 50% alternative decreased in conditions in which the gap preceded either all delay stimuli, both delay stimuli for the 50% alternative, or the food stimulus for the 50% alternative, but preference was not consistently affected in conditions in which the gap preceded only the 100% delay stimulus or the blackout stimulus for the 50% alternative. These results support the notion that conditioned reinforcement underlies the finding of suboptimal preference in probabilistic reinforcement procedures, and that the signal for food on the 50% reinforcement alternative functions as a stronger conditioned reinforcer than the signal for food on the 100% reinforcement alternative. In addition, the results fail to provide evidence that the signal for blackout functions as a conditioned punisher.  相似文献   
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