Reliability,Dimensionality, and Internal Consistency as Defined by Cronbach: Distinct Albeit Related Concepts

This article uses definitions provided by Cronbach in his seminal paper for coefficient α to show the concepts of reliability, dimensionality, and internal consistency are distinct but interrelated. The article begins with a critique of the definition of reliability and then explores mathematical properties of Cronbach's α. Internal consistency and dimensionality are then discussed as defined by Cronbach. Next, functional relationships are given that relate reliability, internal consistency, and dimensionality. The article ends with a demonstration of the utility of these concepts as defined. It is recommended that reliability, internal consistency, and dimensionality each be quantified with separate indices, but that their interrelatedness be recognized. High levels of unidimensionality and internal consistency are not necessary for reliability as measured by α nor, more importantly, for interpretability of test scores.     

Promoting Student Learning in Criminal Justice,STEM, and Forensic Science: Aggie Sleuth Initiative (AggieSI)-Guided Inquiry Learning Experience

This study reported the first interdisciplinary Aggie Sleuth Initiative (AggieSI) conducted between the Departments of Political Science and Criminal Justice, Sociology and Social Work and Chemistry in order to interest underrepresented minority students in the field of forensic science at North Carolina Agricultural and Technical State University (NCA&T). The AggieSI project involved a “simulated crime scene” and a “hypothetical narrative” that provided the “simulated circumstances” for the AggieSI exercise. The students worked in groups on their AggieSI projects in a guided inquiry laboratory experiment format. The students found their AggieSI project motivating, promoting the students’ critical thinking, problem-solving and teamwork skills with students from other departments. This project also promoted mutually beneficial collaborations and partnerships between NCA&T and the local Police Department to further promote forensic studies and to ensure justice and public safety in our community.     

故宫博物院的信息系统建设

在新时代,博物馆无论要更好地履行社会教育职能,还是要优化内部管理,都离不开信息系统所发挥的至关重要的作用。博物馆信息系统建设的内容架构主要分为三部分：数字资源系统建设、管理信息平台建设和数字化文化展示平台建设。这三部分承担了不同的目标：数字资源系统建设、是博物馆信息系统建设的基础,管理信息平台建设的目标是提升工作效率,数字化文化展示平台建设的目标是加深博物馆知识受众的文化感受。故宫博物院的信息系统建设就遵循了以上思路。     

Easier Said Than Done: Rejoinder on Sijtsma and on Green and Yang

The main points of Sijtsma and Green and Yang in Educational Measurement: Issues and Practice (34, 4) are that reliability, internal consistency, and unidimensionality are distinct and that Cronbach's alpha may be problematic. Neither of these assertions are at odds with Davenport, Davison, Liou, and Love in the same issue. However, many authors in the testing community mention these terms not only together, but sometimes as if they are synonymous. Moreover, Cronbach's coefficient alpha is very popular as an index of reliability. Thus, articles discussing alpha are not only appropriate, but necessary. Our concerns are the same as formed the genesis of prior (2009) articles by these same authors, Sijtsma and Green and Yang. This rejoinder also makes comments about item parcels when tests are multidimensional and about factor analytic approaches to assessing reliability.     

Adaptive Instructional Strategies for Teaching Rules in Mathematics

These researchers explored ways of adapting instruction to individual students. In one experiment, as an incentive for focusing on more difficult learning tasks, they assigned more points to tasks predicted to be difficult for the student. In a second experiment, they varied both incentives and number of examples offered to demonstrate the tasks, again on the basis of pretest scores. Included is a discussion of how the findings-that both techniques are beneficial—can be applied in classroom instruction. The authors acknowledge the contribution of Duncan N. Hansen, who directed the research project involving performance of the present studies and participated in the writing of earlier drafts. Requests for reprints should be sent to Steven M. Ross, Foundations of Education, Memphis State University.