Special Theory of Relativity,Conceptual Change and History of Science

The problem of the learning of Special Theory of Relativity by secondary and college students is analysed. It is stressed that the results of the studies which attempted to evaluate students' learning are ambiguous and intriguing. Also the history of the emergence and acceptance of the theory by the scientific community itself at the beginning of the 20th century is analysed. Three fundamental steps are described: a) the publication of Lorentz's Transformation Equations, their interpretation in the context of the Electron Theory and their consequent acceptance by the scientific community; b) the presentation by Einstein of two postulates, namely the Relativity Principle and Einstein's Principle of the Invariance of the Speed of Light, and their partial acceptance; c) the rejection of the Electron Theory and the final acceptance of the Theory of Relativity simultaneously with the development of the General Theory of Relativity. The analogy between historical and learning processes provides some suggestions to improve the teaching of the theory.     

Quantitative analysis of Brazilian football players' organisation on the pitch

The purpose of this study was to characterise Brazilian teams' coverage area and spread on the pitch while attacking and defending and to analyse the teams' organisation in tackle and shot on goal situations. We obtained the trajectories of 223 players in eight games with a tracking method. Team area was defined as the area of the convex hull formed by players' positions. Team spread was defined as the Frobenius norm of the distance-between-player matrix. We calculated teams' area and spread over time and in situations of shots on goal (n = 233) and tackles (n = 1897). While the players attacked, spread and area (median +/- confidence interval) ranged from 322.9 +/- 0.8 to 387.8 +/- 1.0 m and from 905.4 +/- 4.4 to 1407.6 +/- 5.5 m2, respectively. On defence, the values were smaller (p < 0.05) and ranged from 283.4 +/- 0.9 to 325.8 +/- 0.9 m and from 773.8 +/- 4.6 to 1158.4 +/- 5.5 m2 for the spread and the area. In defending circumstances, the teams presented a greater area and spread when they suffered shots on goal than when the teams performed tackles. In attacking situations, the teams presented a greater area and spread when they suffered tackles than when they performed shots on goal. The results allowed showing the attacking-defending interaction between Brazilian teams.     

The influence of serve characteristics on performance in men's and women's high-standard beach volleyball

The precise influence of serve type and serve ball speed on beach volleyball performance is unclear. We examined the relationship between serve type and speed and their effectiveness during the 2008 Men's and Women's Open World Tour Tournament. Three hundred and seventy-eight and 375 serves performed by men and women respectively from the main draw tournament were analysed. Serve speed was recorded using a radar gun. Two expert observers recorded serve speed, serve mode, serve effectiveness and rally outcome. There was no relationship between serve speed and its effectiveness for men (r = -0.047, P > 0.05) and for women (r = -0.048, P > 0.05). However, there was a relationship between serve ball speed and its effectiveness both for men and women, when speed was categorised into three groups. There was a better balance between negative and positive outcomes at medium speeds for men and at low and high speeds for women. There was a relationship between ranking and serve ball speed only for women and between ranking and type of serve for both genders. There was no relationship between rally outcome and serve effectiveness. The combination of high ball speed and jump serve is characteristic of high ranking women but not of men.     

Production technologies and financial performance: The effect of uneven diffusion among competitors

We explore the impact of a production technology on financial performance from the perspectives of technology diffusion and competitive strategy theory. We analyse how diffusion at firm and market levels influences the returns from the technology. We suggest that firm heterogeneity in the level of technology use leads to competitive advantages for relatively intensive adopters. We empirically test our propositions through the analysis of the diffusion of the Automated Teller Machine among Spanish savings banks between 1986 and 2004. Our results show that it is not the absolute but the relative level of use that drives the impact of the technology on profitability. Furthermore, as the technology is more intensively deployed in the market, the profitability of every firm decreases. Interestingly, in our empirical setting, this negative effect eventually leads to an aggregate negative impact on the profitability of the savings banks.     

Peer and neighborhood effects: Citation analysis using a spatial autoregressive model and pseudo-spatial data

Spatial analysis approaches have been long since adopted in citation studies. For instance, already in the early eighties, two works relied on input-output matrices to delve into citation transactions among journals (Noma, 1982; Price, 1981). However, the techniques meant to analyze spatial data have evolved since then, experiencing a major step change starting from the turn of the century or so. Here I aim to show that citation analysis may benefit from the development and latest improvements of spatial data analysis, primarily by borrowing the spatial autoregressive models commonly used to identify the occurrence of the so-called peer and neighborhood effects. I discuss features and potentialities of the suggested method using an Italian narrow academic sector as a test bed. The approach proves itself useful for identifying possible citation behavior and patterns. Especially, I delve into the relationships between citation frequency at author level and years of activity, references, references used by the closest peers, self-citations, number of co-authors, conference papers, and conference papers authored by the nearby researchers.     

Irlen Colored Filters in the Classroom: A 1‐Year Follow‐Up

Colored filters are used to treat Irlen syndrome (IS), a controversial disorder posited to be the cause of a substantial proportion of reading difficulties. Previously, we found that Irlen colored filters do not produce any short‐term alleviation of reading difficulties in schoolchildren aged 7–12. Here, we tested whether colored filters show benefits with longer‐term use, in a subset of the original sample. We measured reading rate with and without filters in 18 children diagnosed with IS, who had been using the filters for 1 year, and compared the progression of their reading ability across the year against 10 poor‐reader control children. The Irlen‐treatment group did not read any faster when using their colored filter, and showed no disproportionate gain in reading progress across the year compared to controls. We conclude that Irlen filters do not benefit reading, even after 1 year of use.     

The impact of individual consultation on the teaching of younger versus older faculty

This study examines the effect of age of instructor on student ratings of teaching performance after individual consultation. Instructors self-presented over an 11-year period at a large Canadian university teaching service, where each received one of three interventions. End of term student ratings of the teaching of younger and older instructors are compared before consultation, immediately post consultation, and 1–3 years after year of consultation. Younger faculty obtained significantly improved ratings immediately after consultation, while older faculty achieved significant rating increases 1–3 years post consultation. Results from an earlier study on the impact of individual consultation on teacher ratings are reevaluated using this larger sample of faculty. Generally, results in this analysis parallel the original research. Consultation produced changes in student ratings both immediately after consultation as well as longitudinally, thus confirming the utility of intervention in producing enduring pedagogical improvements. Control analyses ensured that improvements were a result of the interventions and not an artefact of time.     

W5″ Test: A simple method for measuring mean power output in the bench press exercise

The aims of the present study were to assess the validity and reliability of a novel simple test [Five Seconds Power Test (W5″ Test)] for estimating the mean power output during the bench press exercise at different loads, and its sensitivity to detect training-induced changes. Thirty trained young men completed as many repetitions as possible in a time of ≈5?s at 25%, 45%, 65% and 85% of one-repetition maximum (1RM) in two test sessions separated by four days. The number of repetitions, linear displacement of the bar and time needed to complete the test were recorded by two independent testers, and a linear encoder was used as the criterion measure. For each load, the mean power output was calculated in the W5″ Test as mechanical work per time unit and compared with that obtained from the linear encoder. Subsequently, 20 additional subjects (10 training group vs. 10 control group) were assessed before and after completing a seven-week training programme designed to improve maximal power. Results showed that both assessment methods correlated highly in estimating mean power output at different loads (r range: 0.86–0.94; p?R²: 0.78). Good to excellent intra-tester (intraclass correlation coefficient (ICC) range: 0.81–0.97) and excellent inter-tester (ICC range: 0.96–0.99; coefficient of variation range: 2.4–4.1%) reliability was found for all loads. The W5″ Test was shown to be a valid, reliable and sensitive method for measuring mean power output during the bench press exercise in subjects who have previous resistance training experience.