Improving Statistical Reasoning By Using The Right Representational Format

New results in research on judgment under uncertainty show a way of how to improve the teaching of statistical reasoning. The implications of this research are that (i) successful learning needs doing, and (ii) that the format in which information is represented plays a decisive role. Statistical problems are, for instance, solved much better if the relevant pieces of information are presented as frequencies rather than probabilities. It also helps a lot if random processes can be observed rather than only read about. A computer program is presented that incorporates these implications from psychological research. The software accompanies an elementary text book on probability theory to be used in high school.