Using latent transition analysis to identify effects of an intelligent tutoring system on reading comprehension of seventh-grade students

Latent transition analysis (LTA) was conducted on data from a recent cluster randomized controlled study of 1808 seventh-grade students’ use of a web-based intelligent tutoring system (ITSS). This analysis goes beyond traditional variable-centered methods to focus on profiles of learners and changes in reading class membership between pre- and post-tests for students with and without receiving ITSS intervention. A four-class model was obtained, consisting of poor readers (class 1), delayed readers (class 2), proficient readers (class 3), and readers with specific deficits in problem and solution (class 4). Analysis showed that students receiving the ITSS intervention were more likely than students without the intervention to transition into the proficient class regardless of their initial reading performance profiles. However, the odds ratio of transitioning into the proficient class (as opposed to staying in the same class) in the ITSS condition, compared to the control, was the highest (4.29) for initial readers with deficits in problem and solution, followed by initial poor readers (1.66) and initial delayed readers (1.50). Findings indicated that students in the ITSS condition had larger reading improvement than students in the control condition, particularly for readers with initial deficits in problem and solution.     

Equity Gains in Bangladesh Primary Education

Although equity is a desirable objective of any form of development intervention, including education, not many studies dwell upon this important area. Information on related trends is even more rare. This essay uses field-level data from Bangladesh to examine equity levels and trends in primary education, including enrolment and quality of learning, focusing on equity for different gender, urban or rural, economic and ethnic groups. The study shows that while some disparity between girls and boys has been eliminated, girls are still far behind boys in terms of learning achievement. Children belonging to poorer families and ethnic minority groups lag behind the respective dominant groups in terms of both enrolment and learning achievement. At the same time, there have been some improvements for hitherto excluded groups such as rural girls and children of the poor. These changes are attributed mainly to 'positive discriminatory' steps taken by the government and non-governmental organizations in favour of such groups. If this trend continues, Bangladesh can look forward to establishing itself as a more equitable society than it is now.     

Diagnosis and treatment of reading disabilities based on the component model of reading: an alternative to the discrepancy model of LD

Currently, learning disabilities (LD) are diagnosed on the basis of the discrepancy between students' IQ and reading achievement scores. Students diagnosed with LD often receive remedial instruction in resource rooms. The available evidence suggests that the educational policy based on this discrepancy model has not yielded satisfactory results. This has led researchers to try other paradigms, such as the component model and response to intervention, for dealing with children with reading disabilities. The component model of reading (CMR) described in the present article identifies the reading component that is the source of reading difficulty and targets instruction at that component. Study 1 describes the CMR and reports on its validity. Study 2 describes the successful outcome of a 7-year CMR-based reading instruction program. Compared to the discrepancy model, the CMR has demonstrated several advantages.     

Evolutionary biology today

“For a biologist”, wrote Sir Peter Medawar, “the alternative to thinking in evolutionary terms is not to think at all”. Yet, at the end of an education in biology in most Indian universities, this is not quite the view of evolutionary biology that one is left with. Evolution is presented summarily, almost as a footnote, rather than as a vital branch of biology providing the conceptual foundation for our modern views about the living world. In this issue ofResonance, we remember Stephen Jay Gould, who wrote extensively and eloquently about evolution for a general audience. It seems fitting, then, to also briefly discuss why evolutionary biology is important, not only conceptually but also in terms of practical applications. In this first part of a series of articles on modern evolutionary biology, we examine why the idea of evolution is so important in our intellectual history, and also take a look at the domain of evolutionary biology as a discipline. Amitabh Joshi studies and teaches evolutionary genetics and population ecology at the Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore. His current research interests are in life-history, evolution, the evolutionary genetics of biological clocks, the evolution of ecological specialization dynamics. He also enjoys music (especially traditional qawali in Braj, Farsi, Punjabi and Urdu), history, philosophy, and reading and writing poetry in Urdu, Hindi and English.     

Simulation and analysis of resin flow in injection machine screw

A method with simulation and analysis of the resin flow in a screw is presented to ease the control of some problems that may affect the efficiency and the quality of the product among existing screws in an injection machine. The physical model of a screw is established to represent the stress, the strain, the relationship between velocity and stress, and the temperature of the cells. In this paper, a working case is considered where the velocity and the temperature distributions at any section of the flow are obtained. The analysis of the computational results shows an ability to master various parameters depending on the specifications.     

Hardy-Weinberg equilibrium and the foundations of evolutionary genetics 2. The inertial state in population genetics

The year 2008 marks the 100th anniversary of the enunciation of the principle defining the inertial state of populations from a genetic viewpoint through the independent publication of papers on the topic by G H Hardy and W Weinberg. In this part, we formally build up the model that underlies the Hardy-Weinberg Equilibrium, as well as its mathematical representation.     

Level and Trend of Basic Education of Children in Bangladesh: 1993-1998

Using data generated through two nationally representative sample surveys, this paper explores the trends in the level of basic education of Bangladeshi children. The instrument used for the purpose was based on the Declaration of the World Conference on Education for All (WCEFA, Jomtien, 1990). The findings reveal that the level of 'basic education' increased very slowly, 26.7% in 1993 to 29.6% in 1998, less than one percentage point per year. Statistically significant improvement was observed in 'life skills knowledge' and 'writing skills', but not in 'reading' or 'numeracy'. Girls progressed in 'reading', 'writing' and 'life skills', while the boys in 'writing' and 'life skills'. Over the period, the level improved for rural children but decreased for urban children. Bangladesh falls much behind the targets of the Jomtien Conference in 1990; it will have to wait until 2093 AD to reach the WCEFA goal. The country has made good progress in increasing the access to primary education, but a massive drive is necessary to improve the quality of education.