1 Seminar 20 By Colin Sundwick

2 SAT Math Scores Variable N N* Mean SE Mean StDev Minimum Q Median Q3 Math μ= σ= 72.14

3 The shape is fairly normal.

4 Random Small Samples Next, I randomly sampled 10 rows of math SAT scores 20 times and recorded the mean of each small sample. 59 5 61 58 63 17 64 65 66 2

5 Stem-and-Leaf Plot Center- 608 Spread- 23.32Shape- fairly normal except for one high value. 59 5 61 58 63 17 64 65 66 2

6 Random LARGE Samples Next, I did the same thing, except with 40 rows instead of 10. 58 8 59 4 59 59 60 0 62 5

7 Stem-and-Lead Plot Center- 610.5 Spread- 10.31 Shape- pretty normal58 8 59 4 59 59 60 0 62 5

8 How do they compare? Samples of 10 Samples of 40 Center- 608Spread- 90 Shape- fairly normal with one apparent outlier, even though the 1.5 x IQR rule doesn’t classify it as one. Center Spread- 37 Shape- normal

9 Boxplots

10 Wages Earned Variable N N* Mean SE Mean StDev Minimum Q1 Median Q3 Earned μ = 3.776 σ= 6.503

11 The graph is clearly skewed right

12 Random Small Samples Next, I randomly sampled 10 rows of wages earned 20 times and recorded the mean of each small sample. 1 67 2 77 3 04 3 799 4 3 4 6 5 3 5 6 6 6 5 7 7 8

13 Stem-and-Leaf Plot Center- 3.2 Spread- 1.68 Shape- skewed right 1 671 67 2 77 3 04 3 799 4 3 4 6 5 3 5 6 6 6 5 7 7 8

14 Random Large Samples Next, I did the same thing, except with 40 rows instead of 10.

15 Stem-and-Leaf Plot Center- 3.4 Spread- .709 Shape- normal

16 How do they compare? Samples of 10 Samples of 40 Center- 3.2Spread- 1.68 Shape- skewed right Center- 3.4 Spread- .709 Shape- normal

17 Boxplots

18 THANK YOU THE END