Seminar 20 By Colin Sundwick

SAT Math Scores Variable N N* Mean SE Mean StDev Minimum Q1 Median Q3 Math 390 56 610.44 3.65 72.14 400.00 560.00 610.00 660.00 μ= 610.44 σ= 72.14

The shape is fairly normal.

Random Small Samples Next, I randomly sampled 10 rows of math SAT scores 20 times and recorded the mean of each small sample. 57 258 58 558 59 5 60 2388 61 58 62 1266 63 17 64 65 66 2

Stem-and-Leaf Plot Center- 608 Spread- 23.32 Shape- fairly normal except for one high value. 57 258 58 558 59 5 60 2388 61 58 62 1266 63 17 64 65 66 2

Random LARGE Samples Next, I did the same thing, except with 40 rows instead of 10. 58 8 59 4 59 59 60 0 60 7899 61 0134 61 568 62 004 62 5

Stem-and-Lead Plot Center- 610.5 Spread- 10.31 Shape- pretty normal 58 8 59 4 59 59 60 0 60 7899 61 0134 61 568 62 004 62 5

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- 609.5 Spread- 37 Shape- normal

Boxplots

Wages Earned Variable N N* Mean SE Mean StDev Minimum Q1 Median Q3 Earned 446 0 3.776 0.308 6.503 0.000 1.000 2.000 4.000 μ = 3.776 σ= 6.503

The graph is clearly skewed right

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 01344 2 77 3 04 3 799 4 3 4 6 5 3 5 6 6 6 5 7 7 8

Stem-and-Leaf Plot Center- 3.2 Spread- 1.68 Shape- skewed right 1 67 1 67 2 01344 2 77 3 04 3 799 4 3 4 6 5 3 5 6 6 6 5 7 7 8

Random Large Samples Next, I did the same thing, except with 40 rows instead of 10. 2 1 2 566 3 001223 3 5778 4 00223 4 8

Stem-and-Leaf Plot Center- 3.4 Spread- .709 Shape- normal 2 1 2 566 3 001223 3 5778 4 00223 4 8

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

Boxplots

THANK YOU THE END