Abstract:

Nowadays statistics plays a major role either in society or in the research fields, with a particular emphasis in decision-making, therefore the importance of statistical inference. Statistical inference teaching is a new chapter, so this is an innovative study in Angola, since the Scientific Council of Polytechnic School of Malanje (PSM, Angola) had to agree to change the course syllabus in order to include the topics of statistical inference, in which confidence intervals and hypothesis testing were proposed by the first time (Osório, 2016).

This work is part of a broader research that has adopted the theoretical framework of the Ontosemiotic Approach (EOS) since we are trying to overcome the error and difficulties of the students, using the semiotic conflict concept. Those conflicts are of two kinds. The conflicts in using the new concepts of confidence intervals and the conflicts that arise by the use of the spreadsheet.

In this smaller work, we focus on the teaching of confidence intervals using the spreadsheet, in the course of Probabilities and Statistics in the PSM (Angola) during the academic year 2017/2018. The statistical inference through teaching confidence intervals in the course of Probability and Statistics of PSM was taught for the first time, as well as the a technologic tool, the spreadsheet.

In this paper, our main goal is to present the classes planning of this module and it is qualitative and descriptive work. After the planning stage, we describe what the students were asked to do with the spreadsheet after completing the suggested problems using paper and pencil. The spreadsheet was selected since all students have it in their laptop and they may easily use it.

During this first implementation of the confidence interval classes, students did find the difficulties and made some of the errors described in the literature. Nevertheless, we noticed a great satisfaction from the students and they were motivated with this theme. The students were very enthusiastic by the use of the spreadsheet and hopefully other topics in this Probabilities and Statistics course will also use it.

Keywords:

Statistical inference teaching, confidence intervals, Angola.