Objectives 1. describe the logic by which it can be concluded that someone can distinguish berween two things 2 state whether random assignment ensures that all uncontrolled sources of variation will be equal 3. define precisely what the probability is that is computed to reach the conclusion that a difference is not due to chance 4. distinguish between the probability of an event and the probability of a state of the world 5. define "null hypothesis 6. be able to determine the null hypothesis from a description of an experiment 7. define "altermative hypothesis"