1. Hypothesis testing Make assumptions. One of them is the “hypothesis.” Calculate the probability of what happened based on the assumptions. If the probability of what happened is too low, reject the hypothesis.

2. Coin • Assumption: The probability of heads is ½. • One toss possibilities: • The assumption implies that each possibility is equally likely.

3. Coin • Assumption: The probability of heads is ½. • Two toss possibilities: • The assumption implies that each possibility is equally likely.

4. Three toss possibilities (each 1/8 =.125):

5. Four toss possibilities (each 1/16 = .0625):

6. Five toss possibilities (each hypothesized to have probability of 1/32 = .03125):

7. If hypothesis is true that heads and tails are equally likely heads

8. Six tosses possibilities, each hypothesized to have a probability of 1/64 = .015625:

10. Cards

11. The probability of correctly naming a card drawn at random is

12. The probability of correctly naming a card drawn at random is 1/52 • … if you hypothesize that every card is equally likely to be drawn