Literature Index

In this study, the schema-theoretic perspective of understanding general discourse was extended to include graph comprehension. Fourth graders (n = 204) and seventh graders (n = 185) were given a prior-knowledge inventory, a graph test, and the SRA Reading and Mathematics Achievement Tests during four testing sessions. The unique predictors of graph comprehension for Grade 4 included reading achievement, mathematics achievement, and prior knowledge of the topic, mathematical content, and form of the graph. The unique predictors for Grade 7 were the same except that prior knowledge of topic and graphical form were not included. The results suggest that children should be involved in graphing activities to build and expand relevant schemata needed for comprehension,

The authors (teachers-researcher) carried out an exploratory study in which they designed , on the basis of a didactic analysis similar to the one proposed by Vallecillos (1996), three problems of hypothesis tests. Our purpose was to analyze the effects of graphic calculators use in the application and understanding of the concepts of p-value and significance level in the solving of these problems. The study was done with students of a statistics course for Social Sciences at the university level.<br>We studied, on the basis of the problem solving activities done by the students, their errors and difficulties concerning the concepts of significance lebel and p-value. We thought that the graphic calculator use was going to promote the use of the graphic and numeric representations. However, we found that the graphic calculator was used only in order to represent the p-value numeric representation. Even though each student "seems to understand" the concepts of p-value or significance level because he or she can resolve a problem, we find that little changes in data, (i.e., change in test laterality), generate new errors.<br>This result and other similar ones suggest the need to reflect about the phenomena that put into play the concepts in question, the kind of diactical activities that are designed and used in order to work with these concepts, and the conceptions and obstacles which are behind the errors made by the students.

Access to a collection of computer programs for the classical distribution functions, particularly if these can be readily used interactively by any student, is an important teaching tool for teachers of probability and statistics. The availability of such a collection allows the teacher and student to concentrate on the concepts and development of probability and statistics with little if any emphasis on the details of determining probabilities from tables. Algorithms are presented that provide a useful array of methods for evaluating the classical distribution functions.

Discusses the use of computer-illustrated texts to teach statistics at the college level. Microcomputer-based software that can be used in the areas of calculation, graphics, simulation, animation, and text presentation is described; and use of the software for lectures, laboratory use, and tutorials is discussed. (three references) (LRW)