Effectiveness of holistic mental model confrontation in driving conceptual change

Prior research on conceptual change has identified multiple kinds of misconceptions at different levels of representational complexity including false beliefs, flawed mental models, and incorrect ontological categories. We hypothesized that conceptual change of a mental model requires change in the system of relations between the features of the prior model. To test this hypothesis, we compared instruction aimed at revising knowledge at the mental model level called holistic confrontation - in which the learner compares and contrasts a diagram of his or her flawed mental model to an expert model - to instruction aimed at revising knowledge at the false belief level - in which the learner is prompted to self-explain the expert model alone. We found evidence that participants who engaged in holistic confrontation were more likely to acquire a correct mental model, and a deeper understanding of the systems of relations in the model than those who were prompted to self-explain the expert model. The results are discussed in terms of their implications for science instruction.     

Life: Complexity and diversity

Evolving patterns of matter and energy gave rise to the cosmos. The earth, itself a dynamic entity, is inhabited by living organisms that have a dialectical relationship with the world around them.     

The Indian monsoon

We, in the monsoonal regions of the world are concerned about the variation of rainfall in space and time and a major aim of monsoon meteorology is to predict these variations. Understanding the basic system responsible for the monsoon and the factors that lead to its variation is a prerequisite for developing models to generate these predictions. In this article, I discuss the basic system responsible for the monsoon — the wind and the rains. Sulochana Gadgil is an honorary Professor at the Centre for Atmospheric and Oceanic Sciences at the Indian Institute of Science. Her main research interests are monsoon dynamics, the coupling of the tropical cloud systems to the oceans. She has also worked with agricultural scientists and farmers to identify farming strategies which are tailored to the rainfall variability experienced over the region. She is interested in evolutionary biology as well and has worked on mathematical models of interactive populations. She enjoys many facets of nature including clouds, birds, butterflies, flowering trees and elephants.     

Life complexity and diversity

The evolutionary history of life is one of continual expansion, of coming into being of increasingly greater diversity of more complex organisms, colonising ever newer environmental regimes. It is a cosmic drama that has become ever more elaborate, as it retires some, but inducts an even larger number of increasingly sophisticated actors into its fold. But the process has by no means been monotonic. It is as if the stage is cleared from time to time to make for fresh beginnings, with major bouts of extinction. Humans are amongst the most complex products of evolution having in turn populated the world with ever growing numbers of complex artefacts. These artefacts are now threatening to overwhelm the diversity of life. But humans may one day engineer life capable of surviving in outer space, and thereby trigger off a new phase of expansion and diversification of living organisms.     

The Indian monsoon

Understanding the nature of the variation in the rainfall that occurs on different spatial scales (from that of a station or a taluk to that of the entire country) and on different time scales (from days to months, to the whole season, to interannual and longer), unraveling the underlying mechanisms and hence predicting the variation is the central problem of monsoon meteorology. In this series of articles, I shall attempt to address the ‘how and why’ of the Indian monsoon. I begin with a brief discussion of what we know about the nature of the observed variability of the rainfall on different regional and time-scales. What we understand about the physics of the monsoon and its variability will be considered in the next part. Finally I consider why we are not able to predict it better than we do and the challenges to be met for substantive improvement in understanding and prediction of the monsoon.