1 in 8 women (12.5%) of women get breast cancer, so P(breast cancer if female) = 0.125

1. 1 in 8 women (12.5%) of women get breast cancer, so P(breast cancer if female) = 0.125 • 1 in 800 (0.125%) of men get breast cancer, so P(breast cancer if male) = 0.00125

2. Two-Way Table • Create a two-way table, with 1000 each of males and females. • What’s the overall (unconditional) probability of breast cancer?

3. Conditional Probability • What’s P(breast cancer if female)? • What’s P(female if breast cancer)? • P(A if B) is NOT the same as P(B if A)!!!

4. Odds Ratio • The odds ratio (OR)is the ratio of the odds of an event in one group to the odds of an event in another group • Odds ratio for breast cancer comparing females to males:

5. Odds Ratio

6. Unit A Essential Synthesis

7. Sample • The Big Picture Population Sampling Statistical Inference Descriptive statistics

8. Chapter 1: Data Collection Was the explanatory variable randomly assigned? Was the sample randomly selected? Yes No Yes No Possible to generalize to the population Should not generalize to the population Can not make conclusions about causality Possible to make conclusions about causality

9. Chapter 2: Descriptive Statistics • Type of summary statistics and visualization methods depend on the type of variable(s) being analyzed (categorical or quantitative)

11. Descriptive Statistics Think of a topic or question you would like to use data to help you answer. • What would the cases be? • What would the variables be? (Limit to one or two variables)

12. Descriptive Statistics How would you visualize and summarize the variable or relationship between variables? • bar chart/pie chart, proportions, frequency table/relative frequency table, odds • dotplot/histogram/boxplot, mean/median, sd/range/IQR, five number summary • side-by-side or segmented bar charts, difference in proportions, two-way table, odds ratio, conditionals • side-by-side boxplot, difference in means • scatterplot, correlation