INDEPENDENCE OF EVENTS: AN ANALYSIS OF KNOWLEDGE LEVEL IN DIFFERENT GROUPS OF STUDENTS

摘要

The objective of this work is discussing independent events, which have been the cause of theoretical confusions showed by students and mathematics in-service teachers. The proposed didactical activity was developed with 34 master students and 22 college students in Brazil, and 27 high school students in Mexico. The students, of different levels, didn't answer the problems effectively because they've used only the intuitive idea of independence, (chronological or informal independence). They were asked also to decide if two events were dependent or independent in a dice tossing situation, and the results showed something like "events are independent because there is only one kind of event: throw dice". The outcomes show that misconceptions of independent events and conditional probability persist even in people who had studied formally these concepts, pointing out the need to develop didactic situations to teach more effectively this content at high school and mainly to mathematics undergraduates.