The role of conceptual conflict in conceptual change and the design of science instruction

Conceptual conflict has long been recognized as a factor that could facilitate student learning. Due, however, to the lack of a convincing explanation of why it occurs, and how it can be resolved, it has seldom been used in instructional design. Its potential use in instruction is particularly relevant in the light of the recent, well-documented finding that students' existing conceptions frequently constitute a barrier to effective learning. This article examines conceptual conflict in the light of an epistemological model of learning as conceptual change. This analysis shows that the conceptual change model provides an explanation of conceptual conflict which is sufficiently detailed to allow it to be used in the design of instruction. The results of two studies, the first of which addressed the concepts of mass, volume, and density, and the second, the concept of speed, show that instruction, designed in this way, is effective in changing students' existing conceptions.     

The study of butterflies

In the second part of the series on butterflies, we look at some general aspects of their structure, flight, fuels and senses.     

An algorithm for the calculation of exact term discrimination values

Term discrimination values have been suggested as an effective means for the selection and weighting of index terms in automatic document retrieval systems. This paper reports an algorithm for the calculation of term discrimination values that is sufficiently fast in operation to permit the use of exact values, rather than the approximate values studied in previous work. Evidence is presented to show that the relationship between term discrimination and term frequency is crucially dependent upon the type of inter-document similarity measure that is used for the calculation of the discrimination values.     

Cultural differences in the perception of critical interaction behaviors in global virtual teams

We investigated whether members of virtual teams from the U.S., India, and Belgium perceived the same interaction behaviors to be critical for team functioning as Dutch members from an earlier study. Thirteen virtual team workers from the U.S., 11 from India, and 11 from Belgium were interviewed by means of the Critical Incident Technique Flanagan [Flanagan, J. C. (1954). The critical incident technique. Psychological Bulletin, 51, 327–358]. The total number of critical incidents from all countries was 493 and most incidents could be grouped into the same 13 categories as those found in the original Dutch study. However, the results showed that the distributions of the critical incidents from the American, Indian, and Belgian respondents differed from those of the Dutch. Indian and Belgian respondents also mentioned a new category of critical incidents: Respectfulness. The cultural differences were interpreted by means of Hofstede's [Hofstede, G. (2001). Cultures consequences: comparing values, behaviors, institutions, and organizations across nations (2nd ed.). Thousand Oaks, California, U.S.: SAGE Publications] dimensions.