Imperfect Testing

The activities in this Pull-Out deal with conditional probability.

Activity 1 introduces conditional probability and provides students with some practice organizing information into two-way tables and tree diagrams.

Activity 2 focuses on the imperfect nature of certain tests, such as testing for drug usage or particular diseases. Your students will be surprised to learn that under certain circumstances the probability of having a particular trait, given that you have tested positive for that trait, can be small.