The Use of Different Translation Devices to Analyze Knowledge-Building in a University Chemistry Classroom

Research in Science Education - This research draws on Legitimation Code Theory (LCT) to understand the epistemic dimension of the higher education classroom discourse of a professor who is well...     

Separating the Odds: Thresholds for Entropy in Logistic Regression

Abstract

Researchers are often reluctant to rely on classification rates because a model with favorable classification rates but poor separation may not replicate well. In comparison, entropy captures information about borderline cases unlikely to generalize to the population. In logistic regression, the correctness of predicted group membership is known, however, this information has not yet been utilized in entropy calculations. The purpose of this study was to, 1) introduce three new variants of entropy as approximate-model-fit measures, 2) establish rule-of-thumb thresholds to determine whether a theoretical model fits the data, and 3) investigate empirical Type I error and statistical power associated with those thresholds. Results are presented from two Monte Carlo simulations. Simulation results indicated that EFR-rescaled was the most representative of overall model effect size, whereas EFR provided the most intuitive interpretation for all group size ratios. Empirically-derived thresholds are provided.     

The Relationship between Parenting Types and Older Adolescents' Personality, Academic Achievement, Adjustment, and Substance Use

The purpose of the present study was to examine Baumrind's T3 conceptual framework using a multiple informant design and an older adolescent population. With 178 college students and their families as participants, the present study found many of the predicted relations between parents' child-rearing style (Authoritative, Democratic, Nondirective, Nonauthoritarian-Directive, Authoritarian-Directive, and Unengaged) and their adolescent children's behavior in the 4 domains assessed: personality, adjustment, academic achievement, and substance use. The differences between parenting types on the criterion measures were not as large as reported in Baumrind's study, and significant effects were predominantly due to the poor scores from children with Unengaged and Authoritarian-Directive parents. The results are discussed in terms of their implications for the Authoritative parenting type, the utility of using a typology, and areas for future research.     

Integrating control generated by positive and negative reinforcement on an operant baseline: Appetitive-aversive interactions

The interaction of opposing motivational states was measured within a design in which rats barpressed for food in one stimulus and to avoid shock in another. Tone and light discriminative stimuli (Sds) were counterbalanced over incentive conditions. Extinction eliminated responding when neither Sd was present. To minimize the influence of competing peripheral operants or reinforcer-elicited behaviors during appetitive-aversive interactions, contingency parameters were manipulated to generate similar rates and patterns of barpressing in both Sds and stimulus-compounding tests were administered in extinction. On these tests, rates in tone, light, and tone plus light (T+L) were equivalent. In contrast, when the same reinforcer (i.e., food or shock avoidance) maintained comparable training rates in tone and in light, in testing, T+L controlled double the rates of the single stimuli—strong additive summation. These results were strikingly similar to those of single-incentive experiments concerned with the contribution of excitatory and inhibitory incentive states to the results of stimulus compounding. Simultaneously presenting two Sds whose implicit stimulus-reinforcer (S-S^r) contingencies were arranged to make them, respectively, conditioned appetitive and aversive exciters (present experiment) produced test results comparable to those of two Sds whose implicit S-S^r contingencies were arranged to make them both conditioned inhibitors. Reciprocal antagonism between these two motive states more than neutralizes them. It appears to produce a negative (i.e., an inhibitory) motive state.     

A Remote Sensing Class Exercise to Study the Effects of El Niño in South America

Satellite remote sensing techniques can be used for conducting environmental change detection studies following a natural disaster. Modern computer technology and free access to global satellite imagery allows educators to introduce undergraduate students to the fields of remote sensing and encourage their scientific participation through a research assignment that also serves as an educational exercise. The undergraduate physical science laboratory manuals used in higher education that contain printed remote sensing material often fail to effectively achieve these goals. This class exercise utilizes digital satellite imagery for studying the floods that resulted in the Paraná River region in South America during El Niño 1997–98. In addition, it examines vegetation cover and spectral profiles from the study area in order to further understand and assess the changes that were caused by this recurrent climatic anomaly.     

Teaching strategies to create visual representations of key ideas in content area text materials: A longterm intervention inserted in school curriculum

This paper describes a long-term research in which middle-grade school children were taught how to represent visually text key ideas through idea-mapping techniques. It consists of three studies, one for each year of our research. Children were at sixth grade when the instruction began, and they were at eighth grade when it finished. Another group of children from a different public school served as control group. Instruction was very close to the real school conditions: instructors were ordinary teachers, instruction was inserted in the content area curriculum, and ordinary textbooks were regularly employed, though combined with specially elaborated materials. Results were positive in the case of the first and third year, depending on instructional conditions. Positive effects were found on recall, comprehension and learning, but they were different in the three studies. Theoretical and practical implications are discussed.     

Co-teaching as science in the schoolhouse: more questions than answers

The concept of science in the schoolhouse combines knowledge of research-based practices with the complexities of day-to-day life in schools. In this discussion, co-teaching is offered as an example of how advocacy for a practice can outpace the science that supports it. There is a push for co-teaching in contemporary schools, and special educators in great numbers are being asked to join with general educators in meeting the needs of students with disabilities. However, the science behind co-teaching to date is very limited. Studies have examined the implementation of co-teaching as a general service delivery option, but much less attention has been paid scientifically to the character and quality of the co-taught instruction or to the impact of co-teaching on student outcomes. Within this context, I also examine how Crockett's four recommendations to support science in the schoolhouse could address the questions about co-teaching for which there are few answers.     

Performance of the S[... formula ...]2 Statistic for the Multidimensional Graded Response Model

S−χ2 is a popular item fit index that is available in commercial software packages such as flexMIRT. However, no research has systematically examined the performance of S−χ2 for detecting item misfit within the context of the multidimensional graded response model (MGRM). The primary goal of this study was to evaluate the performance of S−χ2 under two practical misfit scenarios: first, all items are misfitting due to model misspecification, and second, a small subset of items violate the underlying assumptions of the MGRM. Simulation studies showed that caution should be exercised when reporting item fit results of polytomous items using S−χ2 within the context of the MGRM, because of its inflated false positive rates (FPRs), especially with a small sample size and a long test. S−χ2 performed well when detecting overall model misfit as well as item misfit for a small subset of items when the ordinality assumption was violated. However, under a number of conditions of model misspecification or items violating the homogeneous discrimination assumption, even though true positive rates (TPRs) of S−χ2 were high when a small sample size was coupled with a long test, the inflated FPRs were generally directly related to increasing TPRs. There was also a suggestion that performance of S−χ2 was affected by the magnitude of misfit within an item. There was no evidence that FPRs for fitting items were exacerbated by the presence of a small percentage of misfitting items among them.