Learning Processes in Chemistry: Drawing Upon Cognitive Resources to Learn About the Particulate Structure of Matter

This article explores 11- to 16-year-old students' explanations for phenomena commonly studied in school chemistry from an inclusive cognitive resources or knowledge-in-pieces perspective that considers that student utterances may reflect the activation of knowledge elements at a range of levels of explicitness. We report 5 themes in student explanations that we consider to derive from implicit knowledge elements activated in cognition. Student thinking in chemistry has commonly been examined from a misconceptions or alternative conceptions/frameworks perspective, in which the focus has been on the status of learners' explicit conceptions. This approach has been valuable, but it fails to explain the origins or nature of the full range of alternative ideas reported. In physics education, the cognitive resources perspective has led to work to characterize implicit knowledge elements—described as phenomenological primitives (p-prims)—that provide learners with an intuitive sense of mechanism. School chemistry offers a complementary knowledge domain because of its focus on the nature of materials and its domination by theoretical models that explain observable phenomena in terms of emergent properties of complex ensembles of “quanticles” (molecules, ions, electrons, atoms, etc.) The themes reported in this study suggest a need to recognize primitive knowledge elements beyond those reported from physics education and suggest that some previously characterized p-prims may be better considered to derive from more broadly applicable intuitive knowledge elements.     

Children’s Models about Colours in Nahuatl-Speaking Communities

This paper presents the development and structure of indigenous children’s ideas about mixing colours as well as their ideas about each colour, derived from their traditions. The children were interviewed both at school and outside it, and an educational proposal was implemented. Ideas expressed in the school context were analysed using the partial possible model, which states that the inferences and explanations used to describe a subject consist of constricting ideas, rules of correspondence, and a set of phenomenological inferences about processes. After identifying these components in the children’s ideas, we developed models to describe their conceptions about mixing colours. We employed a different approach to analyse children’s ideas related to their cultural context. The results showed that children change from a conception that focuses on colours as entities that do not change and as properties of objects (model 1) to the idea that colour represents a quality of substances or objects that can be modified by mixing colours (model 2). Cultural context analysis showed that stories are independent from one another and that they are not connected to colour mixing processes, only to the actions of colour on people. We concluded that students generate independent constructions between school and cultural knowledge.     

Cleaning the slate? School choice and educational outcomes in Spain

Using data from a nation-wide survey on Spanish workers, this paper examines two issues: the determinants of school choice (distinguishing between public and private schools) and the influence of school type on the individual’s educational attainment. For that, bivariate probit models are estimated. The analysis is carried out separately by gender and birth cohort. We find that individuals who have attended a private school come from households with higher socio-cultural level and that having attended a private school does not raise the probability of reaching a higher degree, once potential endogeneity of school choice and educational outcomes are taken into account. However, the latter result depends on the instrumental variable used for observed school type in models of demand for higher education.     

Correlation between variables subject to an order restriction,with application to scientometric indices

Variables subject to an order restriction, for instance Y ≤ X, have a bivariate distribution over a non-rectangular joint domain that entails a non-null and potentially large structural relation even if the variables show no association (in the sense that particular ranges of values of X do not co-occur with particular ranges of values of Y). Order restrictions affect a number of scientometric indices (including the h index and its variants) that are routinely subjected to correlational analyses to assess whether they provide redundant information, but these correlations are contaminated by the structural relation. This paper proposes an alternative definition of association between variables subject to an order restriction that eliminates their structural relation and reverts to the conventional definition when applied to variables that are not subject to order restrictions. This alternative definition is illustrated in a number of theoretical cases and it is also applied to empirical data involving scientometric indices subject to an order restriction. A test statistic is also derived which allows testing for the significance of an association between variables subject to an order restriction.