Toh, Tin Lam

Geographical origin of extra virgin olive oil is a factor that consumers may take into account when making purchasing decisions. Oils that are labelled to be from regions famous for olive cultivation may be assumed to be of higher quality. However, difficulties in the authentication of the geographical origin of olive oils arise due to the similarity in chemical compositions of the oils involved. Fourier-transform infrared (FTIR) spectroscopy has been found to be a viable technology for the classification of oil samples by geographical origin. However, classical methods involving dimension reduction before model fitting usually yield models that are more challenging to interpret. Sparse fused group lasso logistic regression (SFGL-LR) is used with FTIR spectroscopic data to discriminate between Greek and non-Greek organic extra-virgin olive oils. The prediction performance is also compared with that obtained by partial least squares linear discriminant analysis (PLS-LDA). While both methods give comparable good prediction performance, with more than 90% accuracy in classification, the SFGL-LR model demonstrates improvements in the interpretability of the model coefficients.

In Nov 2002, a research team in the National Institute of Education, NTU, launched a cross-discipline quasi-experimental study on “Positive Social Climate for Enhancing Students’ Math Self-concept”. Its main objective is to find the attributes (variables) in the social climate which are accountable for the increase of self-concept of Secondary Two students in the Math remedial classes in Singapore neighbourhood schools. Phase One of this study is Instrumentation: validating the scales used in the measurement of treatment effect. Phase Two is Intervention: the teachers’ / tutors’ interactions with students, the enhancement of students’ capabilities and confidence. These teachers / tutors will attend workshops conducted before the intervention in Phrase Two. The Pretest results will help identify students with high or low Math Self-concept. And the Posttest will help measure the effect of invention on these students’ Math Self-concept. Factors contributed to the significant changes will also be explored. H.W. Marsh’s Self-Description Questionnaire (SDQ-II, 1990) and B. Fraser’s “What is happening in this Class?” questionnaire were validated together with the Motivational Orientation scale and Intellectual Achievement Responsibility (IAR) questionnaire in Phase One. More than 700 Secondary Two students from four neighbourhood schools took part in the survey. Some preliminary findings in Phase One of this study will be presented in this paper. Gender and course differences in Math Self-concept and other variables will also be discussed.

We recognize that though teachers may participate in various forms of professional development (PD) programmes, learning that they may have gained in the PD may not always lead to corresponding perceivable changes in their classroom teaching. We offer a theoretical re-orientation towards this issue by introducing a construct we term “concretisation”. Concretisations are resources developed in PD settings which can be converted into tangible tools for classroom use. In theorising such resources, we contribute in informing the design process of teacher professional development for better impact into actual classroom practice. We purport principles of design which render concretisations effective. Subsequently, we test these principles by presenting a specific case of teaching mathematical problem solving.

It is easy to dismiss the work of “teaching students to apply formula” as a low-order priority and thus trivialises the professional knowledge associated with this practice. Our encounter with an experienced teacher—through the examination of her practices and elaborations—challenges this simplistic assumption. There are layers of complexities that are as yet under-discussed in the existing literature. This paper reports a case study of her practices that reflect a complex integration of relevant theories in task design. Through examining her praxis around the theme of “recognise the form”, we discuss theoretical ideas that can potentially advance principles in the sequencing of examples for the purpose of helping students develop proficiency in applying formula.

The role of the teacher is central to the success of any curriculum innovation. Thus, teachers’ professional development has become an increasingly important subject of discussion in recent education literature. In the design and implementation of the project reported here, teachers’ preparation for the problem-solving curriculum featured prominently. This paper discusses the challenges of selecting a suitable problem and ways of using it productively within a professional development programme that the authors carried out for the teachers involved in the project.

In this chapter, we discuss the comics package we have developed to teach lower secondary school statistics of the mathematics curriculum. Most people would think that comics for classroom instruction can at most stop at arousing students’ interest in the subject, especially among the low-attaining students. However, we assert that using comics in teaching lower secondary statistics can introduce the students to much of the statistical processes within contexts that are meaningful to students, invite them to engage in higher order thinking tasks in order to develop their critical thinking ability. We also discuss snapshots of how one teacher enacted the statistics lessons based on our comics teaching package, and two teachers’ response to the comics package.

Studies have shown that teachers do not have good understanding of calculus concepts. This paper reports a study of teachers' content knowledge of calculus, on 27 in-service mathematics teachers. A questionnaire dealing with the concept images and concept definitions of various calculus concepts was administered to the group of participating teachers. The responses to the questionnaire showed that most of the participants had not built up sufficiently rich and comprehensive concept images related to the various differential calculus concepts, and they generally turned to procedures in handling calculus tasks. This study sheds light on the type of calculus content needed by school teachers.