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- 23.32
Shape- 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 normal
58 8
59 4
59 59
60 0
62 5

8. How do they compare? Samples of 10 Samples of 40 Center- 608
Spread- 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 67
1 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- 3.2
Spread- 1.68
Shape- skewed right
Center- 3.4
Spread- .709
Shape- normal

17. Boxplots

18. THANK YOU
THE END