AP Stats ‘Must Haves’ 1.NOTEBOOK 2. PENCIL 3. GRAPHING CALCULATOR The Role of Statistics Case 1: Sexual Discrimination Problem Case 1: Sexual Discrimination Problem Recently, a large company had to fire 10 employees because of the sluggish economy. Of these 10 employees, 5 were women. However, only 1/3 of the company’s employees were women. This discrepancy has led the women who were fired to file a sexual discrimination lawsuit. Do they have a legitimate claim? What are our options in this case? -they have a legitimate claim--the company fired a higher proportion of women on purpose -they DON’T have a legitimate claim-- this could have occurred by random chance Let’s SIMULATE the case Let’s simulate the firing by using a population of beads to represent the population ofRED: the company FEMALE EMPLOYEES BLUE: MALE EMPLOYEES Does this give evidence of discrimination? HECK NO! Since it is somewhat likely to get 5 or more women by random chance alone, we do not have evidence that women were discriminated against. Probability = 21.3% Distribution How do you interpret a graph ? Constructing Dotplots Label your axis and title your graph. Scale the axis based on the values of the variable Mark a dot above the number of the horizontal axis. The number of goals scored by each team in the first round of California Southern Section Division V high school soccer playoffs: 5 3 0 1 1 5 0 0 7 3 2 0 1 1 0 0 4 1 0 0 3 2 0 0 2 3 0 1 Dotplot Goals Scored in California Division 5 Soccer Playoffs S 0 C S | | | | | | | | | 0 1 2 3 4 5 6 7 8 Spread Giving the smallest and largest value Outlier Falls outside the overall pattern of the graph Finding a value that divides the observation in half: large values small values Center Shape Long tail to the right or to the left Stemplots How to construct a stemplot (aka stem and leaf plot) Stem: first digit Leaf: remaining digit(s) Example: This lists the number of points Philip’s team scored in last season’s basketball game: 78 84 67 75 86 89 56 93 90 81 77 84 5 6 6 7 7 578 8 14469 9 3 Practice Construct a stemplot on the caffein content (in milligrams)for an 8-ounce serving of some popular soft drinks 20 15 23 29 23 15 23 31 28 35 27 37 27 24 26 47 28 24 28 28 16 38 36 35 37 27 25 47 27 29 26 43 28 35 25 Homework 1.How many women fired would make you suspicious? 2.In statistics, is it possible that we make the wrong decision? 3.How will you compute for the probability of this case?