Mission to Planet Markle: Problem-Based Learning for Teaching Elementary Students Difficult Content and Practices

Research in Science Education - Young children can struggle to learn difficult disciplinary content and important skills for practicing science. Problem-based learning (PBL) may be useful for...     

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.     

Variability in children’s early reading strategies

The present study examines the development of sight word reading in young children by examining changes in their self‐reported reading strategies over time. A sample of 65 five to seven year olds were asked to read 40 real word items, all carefully matched for letter length and word frequency, on three separate occasions. Changes in the children’s word identifications were measured using immediately retrospective verbal self‐reports. Overall, the results showed some variability in the children’s self‐reported reading strategies. Over time the children relied less on phonological strategies and moved towards reliance on directly retrieving words from memory. This change was most evident in the older children; while both year groups showed similar patterns of shifting reliance from explicit phonological strategies to retrieval, this shift was simply less frequent among the younger children. An analysis of word‐specific changes in reading strategies showed that the older children had a better sight vocabulary for more complex word items. These findings provide further support for Ehri’s mediated phase theory in explaining children’s development in learning to read.     

The community college and the disadvantaged

The objective of this study is to empirically explore the extent to which public two-year colleges in this country are characterized by open admissions policies and by comprehensive curricula, as well as the extent and nature of programs for the disadvantaged within these institutions. Utilizing a stratified sampling design developed by the research staff of the American Council on Education, a precoded original questionnaire was mailed in the spring of 1971 to the chief administrative officer for each institution in the sample. It was found that only a little over half of the colleges have the curricula offerings and admissions policies of exemplary community colleges, but that all reported special courses, programs, or services for the academically disadvantaged minority group. However, only 40% of our sample indicated that they have developed special programs (as opposed to courses or services). Too, community colleges with programs require (1) more resources in preparing faculty for dealing effectively with the disadvantaged, (2) additional emphasis on recruitment of the disadvantaged, and (3) more attention to developing courses in ethnic studies.An earlier version of this paper was presented at the annual meeting of the American Educational Research Association, New Orleans, February 1973. Partial support for the project from which this paper was developed was provided by the U.S. Office of Education (Contract #OEC-0-70-4283 (399) to the Pennsylvania State Department of Education). The author also wishes to acknowledge the contribution of Reynolds Ferrante, graduate student, Pennsylvania State University, who assisted in the literature review and questionnaire development of the project.