Parameter Recovery in the Graded Response Model Using MULTILOG

The graded response model can be used to describe test-taking behavior when item responses are classified into ordered categories. In this study, parameter recovery in the graded response model was investigated using the MULTILOG computer program under default conditions. Based on items having five response categories, 36 simulated data sets were generated that varied on true θ distribution, true item discrimination distribution, and calibration sample size. The findings suggest, first, the correlations between the true and estimated parameters were consistently greater than 0.85 with sample sizes of at least 500. Second, the root mean square error differences between true and estimated parameters were comparable with results from binary data parameter recovery studies. Of special note was the finding that the calibration sample size had little influence on the recovery of the true ability parameter but did influence item-parameter recovery. Therefore, it appeared that item-parameter estimation error, due to small calibration samples, did not result in poor person-parameter estimation. It was concluded that at least 500 examinees are needed to achieve an adequate calibration under the graded model.     

复杂系统、知识管理与组织学习过程动态模型研究

知识经济时代的组织是一个具有无尺度网络结构的复杂系统。知识管理是知识经济时代的必然要求。组织学习作为组织获取核心竞争力和可持续发展能力的重要手段，是一个动态的过程。本文在系统回顾相关研究成果的基础上，从复杂系统的视角对知识经济时代复杂环境下的组织学习动态复杂过程进行了系统的模型整合和创新，并对构建学习型组织可能遇到的障碍进行了一系列对策分析。     

Teaching About Sound: A Select Historical Examination of Research

The teaching of the science topic sound, a popular topic in science instruction, is selectively analyzed over the past century using evidence excerpted from a prominent teacher practitioner journal (School Science And Mathematics). Shifting innovative recommendations on how teachers of science should teach the sound topic are identified in the categories of content and pedagogy. Historical connections to the scientific development of sound, identification of what constitutes the subject matter of sound, recommended general pedagogical strategies, and best practices for teaching strategies associated with the sound concept are examined. Discussion relates to the influence of contextual factors in a given time period (social and theoretical) on the design of curriculum materials used to guide instructional practice. One implication for science teacher education is the need for science teachers to develop an historically and philosophically grounded perspective by examining both the teaching practices on a science topic over an extended time and the historical scientific development of the science topic.     

Results of an assessment to identify potential barriers to sustainable agriculture on American Indian reservations in the Western United States

Purpose: This paper reports the results of survey research conducted with tribal producers between 2011 and 2012 on 19 of the largest American Indian reservations in Idaho, Nevada, North Dakota, Oregon, South Dakota, and Washington. The purpose of the research was to identify potential barriers to sustainable agriculture on reservation lands. This article reports the results of this research in an effort to promote Extension professionals' understanding of these barriers, which may help to improve outreach programs on American Indian reservations. Understanding the obstacles to sustaining agriculture that American Indian tribes face may inform international agricultural outreach efforts to increase food security targeting indigenous and tribal peoples worldwide.

Design/Methodology/Approach: American Indian agricultural producers comprised the study group. Study objectives included: (1) identify agricultural and natural resource issues of greatest concern to a self-selected sample of tribal agricultural producers on reservation lands; (2) evaluate access to Extension and other US Department of Agriculture outreach and assistance programs; and (3) evaluate the quality of these programs in terms of their relativity to tribal needs.

Findings: Study results indicate that tribal agricultural producers surveyed ranked 29 of 39 agricultural and natural resource issues as a concern. Similarly, they rated access to and quality of outreach programs as fair. Further, tribal producers operating on reservation trust land rated issues more severely than did tribal producers operating on fee simple lands.

Practical Implications: Results of this research will help Extension and other outreach professionals to understand the barriers indigenous and tribal peoples face in sustaining agricultural operations, particularly tribal groups living on federally reserved trust lands, such as American Indians. An increased understanding can inform agricultural policy-makers and outreach professionals in improving programs designed to increase agricultural sustainability, improve food security, enhance economic well-being and improve quality of life of indigenous and tribal peoples worldwide.

Originality/Value: This research provides important information to agricultural policy-makers and Extension professionals striving to sustain agricultural productivity and enhance food security with indigenous and tribal peoples.     

Expert Teams in the Academic Library: Going Beyond Subject Expertise to Create Scaffolded Instruction

This article explores the way librarians define, leverage, and amplify expertise in a twenty-first century academic library. An expert team comprised of a nursing librarian, online learning librarian, information-literacy librarian, and assessment librarian sorted the learning outcomes from the Information-Literacy Competency Standards for Nursing created by the Health Sciences Interest Group taskforce of the Association of College and Research Libraries (ACRL) by grade-levels. Results found distinguishing experts within a library supports the customization of scaffolded instruction. Additionally, using expert teams in academic libraries supports the larger mission of universities to integrate libraries into teaching and research.