Schema theory (1975): retrospectives and prospectives

A brief commentary is provided on the theoretical assumptions, scholarly impact and continuing influence of the schema theory of motor learning (Schmidt, 1975). The traditional contrasts of schema theory to the coordinative structure or dynamical systems framework are reemphasized, and limitations of the variability of practice experiments noted. A central problem for theories of motor learning is change over time, the basis on which learning is typically defined. Most theories including schema have, however, undervalued the importance of the time-dependent nature of change in deference to the almost exclusive study of the amount of some averaged change in behavioral outcome. The persistent and transitory change(s) in movement and outcome that are observed in action are reflections of multiple time scales of change in a dynamical system.     

The effects of work – rest duration on intermittent exercise and subsequent performance

This study examined the effects of different work?–?rest durations during 40?min intermittent treadmill exercise and subsequent running performance. Eight males (mean?±?s: age 24.3?±?2.0 years, body mass 79.4?±?7.0?kg, height 1.77?±?0.05?m) undertook intermittent exercise involving repeated sprints at 120% of the speed at which maximal oxygen uptake (v-[Vdot]O_2max) was attained with passive recovery between each one. The work?–?rest ratio was constant at 1:1.5 with trials involving short (6:9?s), medium (12:18?s) or long (24:36?s) work?–?rest durations. Each trial was followed by a performance run to volitional exhaustion at 150% v-[Vdot]O_2max. After 40?min, mean exercise intensity was greater during the long (68.4?±?9.3%) than the short work?–?rest trial (54.9?±?8.1% [Vdot]O_2max; P?<?0.05). Blood lactate concentration at 10?min was higher in the long and medium than in the short work?–?rest trial (6.1?±?0.8, 5.2?±?0.9, 4.5?±?1.3?mmol?·?l^?1, respectively; P?<?0.05). The respiratory exchange ratio was consistently higher during the long than during the medium and short work?–?rest trials (P <?0.05). Plasma glucose concentration was higher in the long and medium than in the short work?–?rest trial after 40?min of exercise (5.6?±?0.1, 6.6?±?0.2 and 5.3?±?0.5?mmol?·?l^?1, respectively; P?<?0.05). No differences were observed between trials for performance time (72.7?±?14.9, 63.2?±?13.2, 57.6?±?13.5?s for the short, medium and long work?–?rest trial, respectively; P = 0.17), although a relationship between performance time and 40?min plasma glucose was observed (P?<?0.05). The results show that 40?min of intermittent exercise involving long and medium work?–?rest durations elicits greater physiological strain and carbohydrate utilization than the same amount of intermittent exercise undertaken with a short work?–?rest duration.     

Instructions and recipes in mathematical proofs

Educational Studies in Mathematics - In mathematics education research, proofs are often conceptualized as sequences of mathematical assertions. We argue that this ignores proofs that contain...     

Undisclosed Flexibility in Computing and Reporting Structural Equation Models in Communication Science

The use of structural equation modeling (SEM) in communication research has become increasingly popular in recent years, with SEM being commonly used as the primary method of data analysis in studies published within the field’s journals. However, despite its widespread use, there are persistent misapplications of SEM in published empirical studies in the communication sciences. Of these types of misuse, the most troubling are those related to the exploitation of flexibilities in data collection and analysis. Given the number of decisions that must be made when analyzing and reporting structural equation models, decisions which often remain undisclosed, the potential for researchers to exploit flexibilities in SEM research is high. To assess the extent of this problem, as well as the more longstanding types of misuse (i.e., omission of information and disclosed “bad practice”) identified by prior studies, we undertake a methodical review of studies employing structural equation modeling within major journals in the field of communication between the years 2007 and 2011. Articles were coded on the characteristics of the sample, characteristics of the model tested, as well as for various potential problems that we defined a priori. The most serious issues are identified, and recommendations for future standards in SEM research are suggested.     

Resettling the Thoughts of Ernst Mach and the Vienna Circle in Europe: The Cases of Finland and Germany

Although it is generally assumed that the thoughts of Ernst Mach and the scientific fields he influenced (in this case psychophysics and Gestalt psychology) emigrated from Europe during Second World War they apparently survived in Finland, influencing the Finnish education system. The following article evaluates this relationship and its implications from a historical and an empirical perspective. In empirical studies comparing the education systems of different countries, such as PISA, the Finns are in general regarded as being very successful with their school system. Does this apparent success have anything to do with a Machian influence? Our current research has so far revealed that the Finns have gone through an independent cultural development in two specific aspects: in the idea of the development of the individual personality (Snellman) and in a specific phenomenalism (developed primarily by Eino Kaila, in which Kaila was heavily influenced in this by Ernst Mach). The result can be regarded as a nation-wide “Experiment”, the empirical evaluation of which can be found partly in the statistics of the PISA Studies, especially the evaluation of Finland in relation to other countries.     

Why and how mathematicians read proofs: an exploratory study

In this paper, we report a study in which nine research mathematicians were interviewed with regard to the goals guiding their reading of published proofs and the type of reasoning they use to reach these goals. Using the data from this study as well as data from a separate study (Weber, Journal for Research in Mathematics Education 39:431–459, 2008) and the philosophical literature on mathematical proof, we identify three general strategies that mathematicians employ when reading proofs: appealing to the authority of other mathematicians who read the proof, line-by-line reading, and modular reading. We argue that non-deductive reasoning plays an important role in each of these three strategies.