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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.
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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
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
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
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 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
THANK YOU THE END