Using context variety and students' discussions in recognizing statistical situations

We present a proposal for helping students to cope with statistical word problems related to the classification of different cases of confidence intervals. The proposal promotes an environment where students can explicitly discuss the reasons underlying their classification of cases.     

Measurement error in short-term power testing in young people

The aim of this study was to examine the consistency or reproducibility of measuring cycling peak power in children and adults. Twenty-seven pre-pubertal girls and boys and 27 female and male physical education students (age 9.8 +/- 0.5 and 24.4 +/- 4.3 years, respectively; mean +/- s) participated in the study. All participants performed five tests over 15 days and underwent a habituation session before the study. Each test included four sprints against four different braking forces. We found that braking forces of 7.5% of body weight in children and 10% of body weight in adults were too high for most of the participants to elicit maximal cycling power. Unlike the children, the physical education students improved their performance between session 1 and session 2 (1025 +/- 219 vs 1069 +/- 243 W; P < 0.001). Therefore, to obtain reproducible measures of cycling peak power, a habituation session including a complete test protocol (i.e. warm-up plus three sprints) is highly recommended. When the protocol included three sprints in children and at least two sprints in adults, measurement of cycling peak power was found to be highly reliable (test-retest coefficient of variation approximately 3%). Finally, to avoid performance fluctuations, especially over several consecutive evaluations (e.g. longitudinal studies), it is necessary to maintain high motivation in children.     

Constructivism: Sound theory for explicating the practice of science and science teaching

Critics praise applications of constructivism in science pedagogy, but they argue that constructivism is severely impaired and hopelessly flawed as a theory. Flawed theory should not be employed to explain innovative practice. My purposes are twofold. First and foremost, I present a case to support my own and others' assertions that constructivism is a sound theory with which to explain the practice of science and science pedagogy. In accomplishing my primary purpose, I also fulfill my secondary purpose, to respond to constructivism's critics. My argument is presented in three parts. In Part 1, I delineate the epistemological ground with a brief synopsis of the purpose, nature, and orientation of radical and social constructivism. I then offer a synthesis of their foundations. In Part 2, I offer a constructivist account of five long-standing epistemological issues, including truth, solipsism, experience, instrumentalism, and relativity. Truth is the center piece of the argument, and I show how constructivism avoids the root paradox by embracing truth as coherence. Next, constructivism is shown to be a rejection of solipsism. Then, an account of experience based in neurophysiological theory, emergent properties, and the brain as a parallel data-processing organ is provided to support constructivism's inside-out view of experience, in which meaning making occurs within individual minds and in communities of individuals. In the final segment of Part 2, I present a constructivist account of relativity which focuses on physicists' acceptance of relativity, its translation to constructivist epistemology, and constructivists' request for silence regarding ontology. Response to critics' objections are also presented at appropriate points throughout Part 2. In the third part, I present constructivism as an epistemological foundation for a cybernetic perspective of knowing. I then summarize the value of constructivism in explaining and interpreting the practice of science and science pedagogy. © 1998 John Wiley & Sons, Inc. J Res Sci Teach 35: 501–520, 1998.     

An empirical approach toward the prediction of students' science achievement in the United States and Hubei,China

An empirical approach is adopted in this article to explore a possible model for the prediction of students' science achievement in China and the United States. The construction of the model was based on the ninth-grade data base from Phase II of the Second IEA Science Study (SISS) in the United States, and the SISS Extension Study in the Hubei province of China. The common independent variables of the students' science achievement are classified into five categories: students' gender, attitude, home background, classroom experience, and personal effort, according to distinction between visible and latent characteristics, and scree plots from principal component analyses. Latent factors are represented by the first principal components in each of the four latent categories: students' attitudes, home background, classroom experience, and personal effort. Predictors of the model are constructed by polynomials of the visible and latent factors and their interactions in a multivariate Taylor series. Significant predictors at α = .05 were selected through a backward elimination procedure using the Statistical Analysis System. The structure of the four latent factors and the model complexity are compared between the two countries in terms of their educational, political, social, and cultural contexts. © 1996 John Wiley & Sons, Inc.     

Conquest or Reconquest? Students’ Conceptions of Nation Embedded in a Historical Narrative

This article focuses on university students’ understanding of the concept of nation. First an analysis of this concept from a historiographical point of view is presented. This allows for distinguishing between different conceptions of the nation related to 3 main approaches: the romantic, the modernist, and the ethnosymbolic approaches. Based on this analysis and also taking into account present research about history education and the construction of national identities, 5 different dimensions of the concept are presented: (a) historical subject, (b) identification, (c) territory, (d) legitimate claim, and (e) general concept scheme. Qualitative individual interviews were carried out with 31 Spanish college students about a Spanish foundational historical narrative, embedding the concept of nation, called the Reconquest (711 ad–1495 ad). Results indicated that although students showed tensions in their narratives, romantic conceptions dominated most of them. Possible reasons for the existence of these views are analyzed in terms of how the concept of nation is presented in and out of school. Also, implications for teaching and learning this concept are discussed, looking at learning strategies that could improve the understanding of this concept through its 5 analyzed dimensions.     

Repeated sprint ability in young basketball players: one vs. two changes of direction (Part 2)

The aim of this study was to compare the training effects based on repeated sprint ability (RSA) (with one change of direction) with an intensive repeated sprint ability (IRSA) (with two changes of direction) on jump performance and aerobic fitness. Eighteen male basketball players were assigned to repeated sprint ability and intensive repeated sprint ability training groups (RSAG and IRSAG). RSA, IRSA, squat jump (SJ), countermovement jump (CMJ) and Yo-Yo intermittent recovery level 1 test were assessed before and after four training weeks. The RSA and IRSA trainings consisted of three sets of six sprints (first two weeks) and eight sprints (second two weeks) with 4-min sets recovery and 20-s of sprints recovery. Four weeks of training led to an overall improvement in most of the measures of RSA, but little evidence of any differences between the two training modes. Jump performance was enhanced: CMJ of 7.5% (P < 0.0001) and 3.1% (P = 0.016) in IRSAG and RSAG respectively. While SJ improved of 5.3% (P = 0.003) for IRSAG and 3.4% (P = 0.095) for RSAG. Conversely the Yo-Yo distance increased 21% (P = 0.301) and 34% (P = 0.017) in IRSAG and RSAG respectively. Therefore, short-term repeated sprint training with one/two changes of direction promotes improvements in both RSA and IRSA respectively but the better increase on jump performance shown a few changes on sprint and endurance performances.     

Enhancement and reduction of associative retroactive cue interference by training in multiple contexts

Retroactive cue interference refers to situations in which a target cue X is paired with an outcome in phase 1 and a nontarget cue Z is paired with the same outcome in phase 2, with less subsequent responding to X being seen as a result of the phase 2 training. Two conditioned suppression experiments with rats were conducted to determine whether retroactive cue interference is similarly modulated by a manipulation that influences retroactive outcome interference (e.g., extinction). Both experiments used an ABC renewal-like design in which phase 1 training, phase 2 training, and testing each occurred in different contexts. Experiment 1 found that training the target association in multiple contexts without altering the number of training trials during phase 1 decreased retroactive cue interference (i.e., increased responding consistent with the target association). Experiment 2 found that training the interfering association in multiple contexts without altering the number of interference trials during phase 2 increased retroactive cue interference (i.e., decreased responding consistent with the target association). The possibility of similar mechanisms underlying cue interference and outcome interference is discussed.