To monitor and enhance the learning performance of learning groups in a Web learning system, teachers need to know the learning status of the group and determine the key influences affecting group learning outcomes. Teachers can achieve this goal by observing the group discussions and learning behavior from Web logs and analyzing the Web log data…

This snapshot introduces a computer-based representation and activity that enables students to simultaneously "see" the combinatorial space of a stochastic device (e.g., dice, spinner, coins) and its outcome distribution. The author argues that the "ambiguous" representation fosters student insight into probability. [Snapshots are subject to peer…

When a simple random sample of size n is employed to establish a classification rule for prediction of a polytomous variable by an independent variable, the best achievable rate of misclassification is higher than the corresponding best achievable rate if the conditional probability distribution is known for the predicted variable given the…

Background: The Item Response Theory (IRT) has advantages for measuring Health Related Quality of Life (HRQOL) as opposed to the Classical Tests Theory (CTT). Objectives: To present the results of the application of a polytomous model based on IRT, specifically, the Rating Scale Model (RSM), to measure HRQOL with the EORTC QLQ-C30. Methods: 103…

Cognitive theories posit that exposure-based treatments exert their effect on social anxiety by modifying judgmental biases. The present study provides a conservative test of the relative roles of changes in judgmental biases in governing social anxiety reduction and addresses several limitations of previous research. Longitudinal, within-subjects…

This experiment examined the effects of reinforcement probability on resistance to change of remembering and response rate. Pigeons responded on a two- component multiple schedule in which completion of a variable-interval 20-s schedule produced delayed matching-to-sample trials in both components. Each session included four delays (0.1 s, 2 s, 4…

Experiment 1 investigated the controlling properties of variability contingencies on choice between repeated and variable responding. Pigeons were exposed to concurrent-chains schedules with two alternatives. In the REPEAT alternative, reinforcers in the terminal link depended on a single sequence of four responses. In the VARY alternative, a…

Gilbert Gottlieb's formative role in establishing a science of experimental behavioral embryology is described. His experimental program on the development of species identification served as a model for developmental psychobiologists seeking alternatives to the nature-nurture dichotomies prevalent in the 20th century. Two of the major concepts…

Scientists have associated the El Nino/Southern Oscillation (ENSO) phenomenon with extreme climate events such as flooding in California, droughts in Australia, fires in Indonesia, and increased hurricane activity in the Atlantic Ocean. The popular media is constantly attributing individual storms to the ENSO phenomenon. The reality is that a…

Improving the first-year experience has been part of a broader set of initiatives to respond to concerns about undergraduate education (Astin, Keup, & Lindholm, 2002). This research examined the efficacy of a first-year seminar on student satisfaction and retention at a Research Extensive, urban and public land-grant university. This study…

We present a model allowing the measurement of the returns to plurilingual competences in a small open economy, considered as a reduced model of an open European labour market where different nationalities work together and therefore need to communicate either in one or in multiple languages. Our results suggest that high plurilingual competences…

A model for processes of abstraction, based on epistemic actions, has been proposed elsewhere. Here we apply this model to processes in which groups of individual students construct shared knowledge and consolidate it. The data emphasizes the interactive flow of knowledge from one student to the others in the group, until they reach a shared…

We use data from the Survey of Income and Program Participation (SIPP) to investigate the impact that child Supplemental Security Income (SSI) enrollment has on household outcomes, including poverty, household earnings, and health insurance coverage. The longitudinal nature of the SIPP allows us to control for unobserved, time-invariant…

Everyone knows that teachers do not have unlimited time, a log of experience, or a deep understanding of all the mathematics they teach. To solve this problem, teachers often use textbooks, and the accompanying teacher's resource books, as sources of activities and advice about how to help students learn mathematics. The activity that prompted…

New capabilities in "TinkerPlots 2.0" supported the conceptual development of fifth- and sixth-grade students as they pursued several weeks of instruction that emphasized data modeling. The instruction highlighted links between data analysis, chance, and modeling in the context of describing and explaining the distributions of measures that result…