一类具有阶段结构和功能性反应的捕食系统

研究一类具有阶段结构和功能性反应的捕食系统,讨论了该系统非负边界平衡点的全局渐近稳定性,论述了该生态系统的永久持续生存的充分条件。     

大跨钢管混凝土桁架拱桥的地震反应分析

以巫峡长江大桥为研究背景,通过建立空间结构有限元模型,计算和分析该大桥的动力特性,并运用时程分析法分析该桥的地震反应,采用EI-centro波进行计算,讨论横桥向和竖桥向地震动对地震反应的影响和规律,为大跨度钢管混凝土拱桥的抗震设计和研究提供了理论依据。     

SOLINET's Gulf Coast Libraries Recovery Projects for Public and Academic Libraries

SUMMARY

In 2005, Hurricanes Katrina and Rita damaged many libraries along the Gulf Coast. Due to widespread destruction in communities, library recovery has been slow. With support from the Bill & Melinda Gates Foundation and Andrew W. Mellon Foundation, SOLINET implemented two projects in 2006 to insure that library services remain available in the region. The projects provide temporary public library facilities in communities where libraries were destroyed, distribute grants to restore services at academic libraries and support planning in public libraries, and provide education to facilitate recovery. The projects also address planning for long-term recovery and improved preparedness for future disasters.     

项目反应理论在运动心理测量领域的运用与发展

:IRT模式是否可以用来评价心理运动技能 ,许多学者已经对传统的“技能测量”模式提出了异议 ,在此基础上简述了测量理论的发展和 IRT模式的原理 ,分析了 IRT在运动中的有用性及弊端 ,探讨了 IRT在运动心理行为测量中的未来发展方向     

长三角区域一体化与城市土地利用效率的协同测度及交互响应

城市土地利用效率影响区域一体化中的要素流动方向和产业发展态势,土地利用效率的提高是驱动一体化发展的重要因素.如何有效协调长三角一体化和土地利用的良性关系,成为学界的研究热点.因此,本文基于区域一体化与城市土地利用效率的协同机理分析,构建区域一体化与土地利用效率效率评价体系,解析其时空演变特征;通过灰色关联分析验证了两者...     

A Mixture IRTree Model for Extreme Response Style: Accounting for Response Process Uncertainty

This paper presents a mixture item response tree (IRTree) model for extreme response style. Unlike traditional applications of single IRTree models, a mixture approach provides a way of representing the mixture of respondents following different underlying response processes (between individuals), as well as the uncertainty present at the individual level (within an individual). Simulation analyses reveal the potential of the mixture approach in identifying subgroups of respondents exhibiting response behavior reflective of different underlying response processes. Application to real data from the Students Like Learning Mathematics (SLM) scale of Trends in International Mathematics and Science Study (TIMSS) 2015 demonstrates the superior comparative fit of the mixture representation, as well as the consequences of applying the mixture on the estimation of content and response style traits. We argue that methodology applied to investigate response styles should attend to the inherent uncertainty of response style influence due to the likely influence of both response styles and the content trait on the selection of extreme response categories.     

两种寄生物-单种寄主的功能反应研究

本文研究了两种寄生蜂Aphytis sp.and Aphytis melinus在寄主茶长本圆蚧(Abgrallaspis cyanophylli)上的混合寄生效应。结果表明,在混合种群中,两种蜂的攻击效率都减小到单独做功能反应时的1/10。同时,本文首次提出了两种寄生物—单种寄主的功能反应模型,模拟效果较好。     

Seeing the Forest and the Trees: Comparison of Two IRTree Models to Investigate the Impact of Full Versus Endpoint-Only Response Option Labeling

In this study, we examined the results and interpretations produced from two different IRTree models—one using paths consisting of only dichotomous decisions, and one using paths consisting of both dichotomous and polytomous decisions. We used data from two versions of an impulsivity measure. In the first version, all the response options had labels; in the second version, only the endpoints were labeled. Based on past research, we hypothesized that the endpoints would be selected more frequently in the endpoint-only labeled condition, and the midpoint response option would be selected more frequently in the fully labeled condition. Results from the two models (dichotomous and polytomous) were similar and indicated that our hypotheses were partially supported—specifically, there was no consistent pattern in terms of which condition saw a higher frequency of midpoint response selection. However, our hypotheses regarding extreme responding in the endpoint-only labeling condition were supported.     

Parameter Estimation Accuracy of the Effort-Moderated Item Response Theory Model Under Multiple Assumption Violations

As low-stakes testing contexts increase, low test-taking effort may serve as a serious validity threat. One common solution to this problem is to identify noneffortful responses and treat them as missing during parameter estimation via the effort-moderated item response theory (EM-IRT) model. Although this model has been shown to outperform traditional IRT models (e.g., two-parameter logistic [2PL]) in parameter estimation under simulated conditions, prior research has failed to examine its performance under violations to the model’s assumptions. Therefore, the objective of this simulation study was to examine item and mean ability parameter recovery when violating the assumptions that noneffortful responding occurs randomly (Assumption 1) and is unrelated to the underlying ability of examinees (Assumption 2). Results demonstrated that, across conditions, the EM-IRT model provided robust item parameter estimates to violations of Assumption 1. However, bias values greater than 0.20 SDs were observed for the EM-IRT model when violating Assumption 2; nonetheless, these values were still lower than the 2PL model. In terms of mean ability estimates, model results indicated equal performance between the EM-IRT and 2PL models across conditions. Across both models, mean ability estimates were found to be biased by more than 0.25 SDs when violating Assumption 2. However, our accompanying empirical study suggested that this biasing occurred under extreme conditions that may not be present in some operational settings. Overall, these results suggest that the EM-IRT model provides superior item and equal mean ability parameter estimates in the presence of model violations under realistic conditions when compared with the 2PL model.     

基于农户行为响应的农村居民点整合模式探析——以重庆市合川区兴坝村为例

农村居民点整合作为合理组织和有效配置农村土地资源、改善农村人居环境、促进农业规模经营和提升土地价值的重要手段,对其进行研究具有重要实践意义和理论价值。本研究运用相关行为科学的理论,构建了一个模型对农村居民点整合中农户行为响应的决策过程进行模拟,运用参与式农村评估对模拟过程进行农户调研,结合农户自身资源特征、住房情况与生计发展意愿分析不同类型农户的响应程度,根据不同类型农户农村居民点响应程度的差异凝练出兴坝村农村居民点的4种整合模式：农业发展型整合方式、兼业型整合方式、非农发展型整合方式和保留型整合方式。