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51.
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   
52.
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   
53.
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   
54.
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   
55.
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   
56.
Bicycles are an environmentally-friendly, energy-saving mode of transportation. Public bike-and-ride is a term used to describe the use of public bicycles combined with transit as a means of transportation. A new stated preference (SP) design scheme based on the factors respondents felt were most important was proposed to augment the traditional SP design under complex multi-factor and multi-level situations. iPads were used to automatically administer the survey under each design scheme and collect the choice behavior data for public bike-and-ride. The concept of perceived psychological distance was further proposed and used to estimate Logit models. Comparative analysis of these models shows for the traditional SP design scheme, some factors, including perceived psychological distance, have reduced statistically significant effects on public bike-and-ride choice relative to the new SP design scheme. This indicates that in scenarios with complex decisions, the decision-makers would reduce their consideration of some factors and simplify their decision process making the new SP survey design scheme more suitable to analyze their choice behavior in those cases. Model analysis showed that perceived psychological distance for each traveler is the most critical factor during the decision process for travel behavior analysis. Finally, sensitivity analysis was conducted to determine which factors in the new survey design were important to increase the share of public bike-and-ride users. Practical findings for promoting public bike-and-ride use are presented in addition to theoretical references for improving the traditional survey methods.  相似文献   
57.
Although spelling skill progress has typically been studied within the context of students' responses to written story starters (Deno, Marsten, & Mirkin, 1982; Fuchs & Fuchs, 2011; Hosp, Hosp, & Howell, 2007; Shinn & Shinn, 2002), there has been little research conducted within a curriculum-based measurement framework that has studied spelling progress monitoring on a weekly basis throughout an entire school year. The authors evaluated spelling progress using word triads, defined as a group of 3 words (with the same number of letters) that have a similar phonetic or morphological structure. Successful spelling of word triads as the unit of analysis has the potential to be more useful diagnostically to teachers than successful spelling of single words as the unit of analysis. An alternating series of three 15-word spelling tests were administered weekly to 10 third- and fourth-grade classrooms in the same school district throughout the school year for 8 rounds (1 round = 3 weeks of different but phonetically and/or morphologically similar word lists). Results indicate steady progress throughout the school year in the correct spelling of word triads (despite teacher reporting of no explicit spelling instruction in classrooms using in the words employed in the study). Correlations between the number of correctly spelled word triads with standard scores from a group-administered communication arts test were significant and comparable to alternate spelling test scoring methods. The authors conclude with limitations of the study and implications for practitioners.  相似文献   
58.
Learning progressions have been demarcated by some for science education, or only concerned with levels of sophistication in student thinking as determined by logical analyses of the discipline. We take the stance that learning progressions can be leveraged in mathematics education as a form of curriculum research that advances a linked understanding of students learning over time through careful articulation of a curricular framework and progression, instructional sequence, assessments, and levels of sophistication in student learning. Under this broadened conceptualization, we advance a methodology for developing and validating learning progressions, and advance several design considerations that can guide research concerned with engendering forms of mathematics learning, and curricular and instructional support for that learning. We advance a two-phase methodology of (a) research and development, and (b) testing and revision. Each phase involves iterative cycles of design and experimentation with the aim of developing a validated learning progression. In particular, we gathered empirical data to revise our hypothesized curricular framework and progression and to measure change in students. thinking over time as a means to validate both the effectiveness of our instructional sequence and of the assessments designed to capture learning. We use the context of early algebra to exemplify our approach to learning progressions in mathematics education with a focus on the concept of mathematical equivalence across Grades 3-5. The domain of work on research on learning over time is evolving; our work contributes a broadened role for learning progressions work in mathematics education research and practice.  相似文献   
59.
目的:运用自编幼儿人格发展教师评定问卷对幼儿人格进行追踪测量,探讨其年龄及性别发展特点。方法:用整群抽样法选取3~3.5岁、3.5~4岁、4~4.5岁3个年龄群组幼儿为被试,采用群组序列的追踪设计,进行为期1年半的追踪测量,结合潜变量增长曲线模型和多层线性模型处理数据,探讨幼儿在3~6岁间人格的发展特点。结果:(1)幼儿的智能特征、认真自控、外倾性、亲社会性、情绪稳定性5个人格维度在3~4岁发展最快,4~5岁持续增长但发展速度放缓,到5~6岁时趋于平稳;(2)女孩的认真自控和亲社会性在3岁时显著高于男孩,但在3~6岁间的增长率不存在差异,即女孩的认真自控和亲社会性在幼儿阶段发展水平始终高于男孩。结论:从家庭进入幼儿园的环境变迁促使了幼儿人格的进一步发展,5岁左右幼儿人格开始初步形成;女孩的认真自控和亲社会性水平在幼儿阶段始终高于男孩。  相似文献   
60.
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