Magister Educationis - MEd (Mathematics and Science Education) / The study catered for empirical and metaphysical dimensions of science and IKS. The study employed a quasi-experimental design as well as a qualitative research design. Two cohorts of students from a fictitiously named Culture Secondary School have been used in this study. The list of instruments for data collection were as follows: Conceptions of Fermentation (COF) questionnaire which was used to elicit learnerss pre- and post-test conceptions of fermentation with special reference to traditional beer or Umqombothi an Attitudes to Science (ATS) questionnaire which was used to find out the learners' worldviews, a Science Achievement Test (SAT) which was used to assess the learners' generalised knowledge of fermentation, a classroom observation schedule as well as a focus group interview schedule to gather additional qualitative data. All the instruments were in English with all technical and difficult terms in both English and isiXhosa (the learners’ home language). Both groups were exposed to Science/IKS-based lessons. The only difference between the two groups was that, the experimental group (E group) was exposed to a Dialogical Argumentation Teaching Model (DAIM) and the comparison group (C group) to a traditional teaching approach. The data gathered were both analyzed in terms of qualitative and quantitative descriptions. / South Africa

L'objectif de cette thèse est la construction des tests localement et asymptotiquement optimaux. Le problème traité concerne un modèle qui contient une large classe de modèles de séries chronologiques. La propriété de la normalité asymptotique locale (LAN) est l'outil fondamental utilisé dans nos travaux de recherches. Une application de nos travaux en finance est proposée / The purpose of this phD thesis is the construction of alocally asymptotically optimal tests. In this testing problem, the considered model contains a large class of time series models. LAN property was the fundamental tools in our research works. Our results are applied in financial area

In the case of soil chemical analyses, frequency distributions for some elements show a dissymmetrical aspect, with a very marked spread to the right or to the left. A high frequency of extreme values is also observed and a possible mixture of several distributions, due to the presence of various soil types within a single geographical unit, is encountered. Then, for the outliers detection and the establishment of detection limits, an original outliers detection procedure has been developed; it allows estimating extreme quantiles above and under which observations are considered as outliers. The estimation of these detection limits is based on the right and the left of the distribution tails. A first estimation is realised for each elementary geographical unit to determine an appropriate truncation level. Then, a spatial classification allows creating adjoining homogeneous groups of geographical units to estimate robust limit values based on an optimal number of observations. / Dans le cas des analyses chimiques de sols, les distributions de fréquences des résultats présentent, pour certains éléments étudiés, un caractère très dissymétrique avec un étalement très marqué à droite ou à gauche. Une fréquence importante de valeurs extrêmes est également observée et un mélange éventuel de plusieurs distributions au sein dune même entité géographique, lié à la présence de divers types de sols, peut être rencontré. Dès lors, pour la détection des valeurs aberrantes et la fixation des limites de détection, une méthode originale, permettant destimer des quantiles extrêmes au-dessus et en dessous desquelles les observations sont considérées comme aberrantes, a été élaborée. Lestimation des limites de détection est établie de manière distincte à partir des queues des distributions droite et gauche. Une première estimation par entité géographique élémentaire est réalisée afin de déterminer un niveau de troncature adéquat. Une classification spatiale permet ensuite de créer des groupes dentités homogènes contiguës, de manière à estimer des valeurs limites robustes basées sur un nombre dobservations optimal.