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71.
The urban traffic system is most likely to change in the next years to a mixed traffic with human drivers, vulnerable road users, and automated vehicles. In the past, the development of external communication approaches for automated vehicles focused on scenarios where an automated vehicle communicates with either a pedestrian or a human driver. However, interactions with more than one traffic partner are more realistic. Therefore, a study with 42 participants was conducted with a multi-agent simulation in which an automated vehicle interacted simultaneously with two participants, a pedestrian and a driver of a manual vehicle. In this study, two main scenarios were investigated in order to evaluate the safety and efficiency of the interactions and to determine whether the human road users feel correctly addressed. In one scenario, the pedestrian had to cross the road in front of the automated and the manual vehicle, which were approaching from different sides. In the other, the manual vehicle had to drive through a bottleneck in front of the oncoming automated vehicle, while the pedestrian had to cross the road after both vehicles passed. The communication approach of the automated vehicle consisted of implicit signals using a speed profile and lateral offset within its lane, and explicit signals using an external human–machine interface. The results of the study show that no collisions were observed in terms of safety and no significant negative effects on efficiency were measured. However, in contrast to single agent interactions, a majority of participants felt wrongly addressed in situations where the automated vehicle signals the right-of-way to the other human road user. It can be concluded that the communication approach of the automated vehicle needs to be modified in order to address certain road users more clearly.  相似文献   
72.
探究带宽选择方法、样本量、题目数量、等值设计、数据模拟方式对项目反应理论观察分数核等值的影响。通过两种数据模拟方式,获得研究数据,并计算局部与全域评价指标。研究发现,在随机组设计中,带宽选择方法表现相似;考生样本量和题目数量影响甚微。在非等组设计中,惩罚法与Silverman经验准则表现优异;增加题目量可降低百分相对误差和随机误差;增加样本量导致百分相对误差变大,随机误差减小。数据模拟方式可影响等值评价。未来应重点关注等值系统评估。  相似文献   
73.
本研究将微观发生法设计和虚拟仿真技术相结合,考察了不同特质社会创造性大学生跨情境、跨时间的状态社会创造性的变化特点。结果表明:(1)在四种具体社会问题情境中,个体策略新颖性的变化表现出了跨情境的多样性特点,而策略实用性的变化则主要表现出了跨情境的一致性特点;(2)个体特质社会创造性对其状态社会创造性的表现的影响主要体现在策略的实用性上。  相似文献   
74.
Children may be prepared to associate adult disgust reactions with adult disgust elicitors. To test this, three-year olds (and adults) were presented with two images and an emotive vocalization. The images and vocalizations included stimuli adults found disgusting, fear-provoking, and sad. On one set of trials, the main dependent variable (DV) was time spent looking at each image and on a second set of repeat trials the DV was knowledge of image-sound matches. Fear and disgust vocalizations were both more effective at orienting a child's attention to adult fear and disgust images, than sad vocalizations. Parental disgust sensitivity was associated with this effect, moderated by explicit matching knowledge. Matching knowledge was poor in children and good in adults. These data suggest that in children, fear and disgust vocalizations may both promote attention to stimuli that adults find disgusting and/or fear-provoking, suggesting that “preparedness” may not be wholly emotion-specific.  相似文献   
75.
Growing from demands for accountability and research-based practice in the field of education, there is recent focus on developing standards for the implementation and analysis of single-case designs. Effect size methods for single-case designs provide a useful way to discuss treatment magnitude in the context of individual intervention. Although a standard effect size methodology does not yet exist within single-case research, panel experts recently recommended pairing regression and non-parametric approaches when analyzing effect size data. This study compared two single-case effect size methods: the regression-based, Allison-MT method and the newer, non-parametric, Tau-U method. Using previously published research that measured the Words read Correct per Minute (WCPM) variable, these two methods were examined by comparing differences in overall effect size scores and rankings of intervention effect. Results indicated that the regression method produced significantly larger effect sizes than the non-parametric method, but the rankings of the effect size scores had a strong, positive relation. Implications of these findings for research and practice are discussed.  相似文献   
76.
This article shows how to apply generalized additive models and generalized additive mixed models to single-case design data. These models excel at detecting the functional form between two variables (often called trend), that is, whether trend exists, and if it does, what its shape is (e.g., linear and nonlinear). In many respects, however, these models are also an ideal vehicle for analyzing single-case designs because they can consider level, trend, variability, overlap, immediacy of effect, and phase consistency that single-case design researchers examine when interpreting a functional relation. We show how these models can be implemented in a wide variety of ways to test whether treatment is effective, whether cases differ from each other, whether treatment effects vary over cases, and whether trend varies over cases. We illustrate diagnostic statistics and graphs, and we discuss overdispersion of data in detail, with examples of quasibinomial models for overdispersed data, including how to compute dispersion and quasi-AIC fit indices in generalized additive models. We show how generalized additive mixed models can be used to estimate autoregressive models and random effects and discuss the limitations of the mixed models compared to generalized additive models. We provide extensive annotated syntax for doing all these analyses in the free computer program R.  相似文献   
77.
在多级评分模型下,项目的难度参数或步骤参数有多个,在对多级评分模型进行选题时,通常对项目的多个难度参数用一个综合的指标来概括.当对每个项目的难度参数进行有效的综合后,综合后的难度参数分布发生了改变,这时如果增加适量的平均难度较难或较易的项目进入题库,测验的精度和项目的曝光率都有一定的改善.  相似文献   
78.
以1982~2012年中国期刊网收录的88例追踪研究为对象,从应用现状、设计特征、数据处理三方面分析和评估追踪研究方法在国内心理研究的应用情况及存在的问题。结果显示,2005年之前追踪研究方法应用增长缓慢,2005年开始呈显著增长趋势,研究对象以未成年及成年早期群体为主。主要采用固定样本追踪设计,大部分研究测量2-3次、样本量在10~300之间、持续时间在3年内。61例有缺失的研究中,38例用删除法处理缺失;主要运用 HLM、方差分析、t检验和SEM分析追踪数据。相当部分研究存在测量次数少、样本量较小、持续时间短、被试缺失严重及数据处理方法相对陈旧问题。追踪研究方法的应用应注意,根据理论模型和研究有效性要求确定设计类型和设计特征,根据数据特征选择缺失处理方法和追踪数据分析方法。  相似文献   
79.
Research has demonstrated that on the path from a creative idea to a creative outcome, high creativity motivation and self-efficacy do not necessarily lead to creative behavior. The present study proposed and examined the notion that daily creativity planning could promote creative behavior and contribute to the cultivation of creativity. A total of 77 middle school students (39 students in the experimental group and 38 in the control group) participated in this study, for which a quasi-experimental design was administered. The experimental group conducted a two-week daily planning for creative activities, while the control group did not conduct any intervention. The results showed that students' creativity motivation and creative self-efficacy were at relatively high levels overall and were positively and moderately correlated with creative behavior. Daily planning could effectively facilitate students' creative behavior. These findings point to a promising and simple creativity enhancement strategy for cultivating students to develop the habit of making creative plans in their daily lives.  相似文献   
80.
Designing representative learning tasks is one means to enhance sports practice. Recent work has highlighted how the presence of situational information could help the design of these tasks by shaping intentions and enhancing the affective demands of practice, however this has yet to be empirically tested. This study tested this hypothesis by manipulating the presence of a scoreboard featuring time and score situational information as expert taekwondo athletes fought in practice. Nine taekwondo fighters fought with and without situational information in a counterbalanced order. Behaviour was assessed by tracking fighters' location coordinates to assess fighter-fighter dyad coordination and through notational analysis of attacking actions. Affect and cognition were assessed with mixed-methods that included perceptual scales measuring anxiety, arousal, mental effort, score perception, and post-fight video-facilitated confrontational interviews to explore how conditions differed. The results revealed that the presence of the situational information had significant effects on taekwondo players. When present, fighters reported greater cognitive anxiety (d = 0.39, p < 0.05), somatic anxiety (d = 1.11, p < 0.05) and emotion intensity (d = 0.33, p < 0.05). The enhanced affective demands were associated with behaviour changes that included fighters preferring to spend time at closer distances (d = 0.25, p < 0.05), and more predictable technique selection (d = 1.04, p < 0.05). Qualitative data supported these findings. Players also reported their intentions were coupled to the context of scoreboard. This study reveals that situational information changes the affective and behavioural demands of practice to be more like competition. Further, situational sampling affords performers the opportunity to practice attuning to the relevant affordances for a specific context.  相似文献   
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