Portland State University

About: Portland State University is a education organization based out in Portland, Oregon, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 8370 authors who have published 18640 publications receiving 556553 citations.

Structural equation modeling in practice: a review and recommended two-step approach

Abstract: In this article, we provide guidance for substantive researchers on the use of structural equation modeling in practice for theory testing and development. We present a comprehensive, two-step modeling approach that employs a series of nested models and sequential chi-square difference tests. We discuss the comparative advantages of this approach over a one-step approach. Considerations in specification, assessment of fit, and respecification of measurement models using confirmatory factor analysis are reviewed. As background to the two-step approach, the distinction between exploratory and confirmatory analysis, the distinction between complementary approaches for theory testing versus predictive application, and some developments in estimation methods also are discussed.

An Updated Paradigm for Scale Development Incorporating Unidimensionality and Its Assessment

Abstract: The authors outline an updated paradigm for scale development that incorporates confirmatory factor analysis for the assessment of unidimensionality. Under this paradigm, item-total correlations an...

Motivation in the classroom: Reciprocal effects of teacher behavior and student engagement across the school year.

Abstract: On the basis of a new model of motivation, we examined the effects of 3 dimensions of teacher (n = 14) behavior (involvement, structure, and autonomy support) on 144 children's (Grades 3-5) behavioral and emotional engagement across a school year. Correlational and path analyses revealed that teacher involvement was central to children's experiences in the classroom and that teacher provision of both autonomy support and optimal structure predicted children's motivation across the school year. Reciprocal effects of student motivation on teacher behavior were also found. Students who showed higher initial behavioral engagement received subsequently more of all 3 teacher behaviors. These findings suggest that students who are behaviorally disengaged receive teacher responses that should further undermine their motivation. The importance of the student-teacher relationship, especially interpersonal involvement, in optimizing student motivation is highlighted. What are the factors that motivate children to learn? Educators and parents value motivation in school for its own sake as well as for its long-term contribution to children's learning and self-esteem. Highly motivated children are easy to identify: They are enthusiastic, interested, involved, and curious; they try hard and persist; and they actively cope with challenges and setbacks. These are the children who should stay in school longer, learn more, feel better about themselves, and continue their education after high school. Recent research has borne this out (Ames & Ames, 1984, 1985; Pintrich, 1991; Stipek, 1988). Although motivated students are easy to recognize, they are difficult to find. Research shows that across the preschool to high school years, children's intrinsic motivation decreases and they feel increasingly alienated from learning (Harter, 1981). Why is it so difficult to optimize student motivation? Decades of psychological and educational research

Paradigms Lost and Pragmatism Regained Methodological Implications of Combining Qualitative and Quantitative Methods

Abstract: This article examines several methodological issues associated with combining qualitative and quantitative methods by comparing the increasing interest in this topic with the earlier renewal of interest in qualitative research during the 1980s. The first section argues for the value of Kuhn’s concept of paradigm shifts as a tool for examining changes in research fields such as social science research methodology. The next two sections consider the initial rise of the “metaphysical paradigm” that justified the renewed interest in qualitative research and the subsequent problems that have encouraged efforts to replace that paradigm. The final section of the paper advocates a “pragmatic approach” as a new guiding paradigm in social science research methods, both as a basis for supporting work that combines qualitative and quantitative methods and as a way to redirect our attention to methodological rather than metaphysical concerns.

Microbial biogeography : putting microorganisms on the map

Abstract: We review the biogeography of microorganisms in light of the biogeography of macroorganisms A large body of research supports the idea that free-living microbial taxa exhibit biogeographic patterns Current evidence confirms that, as proposed by the Baas-Becking hypothesis, 'the environment selects' and is, in part, responsible for spatial variation in microbial diversity However, recent studies also dispute the idea that 'everything is everywhere' We also consider how the processes that generate and maintain biogeographic patterns in macroorganisms could operate in the microbial world