Any questions?
More scatter plots
HW problem p.95 2.12 (Predicting a y from an
x: Section 2.3 does this for linear relationships)
Correlation: See Day
10
Get Handout: Finding Correlation
Coefficient r with SPSS: You have to dig it out of the forest.
Try it with Table 1-6, pcttakin v. satmath (negative
r). Try with a subgroup (Subgroup handout)
Read 2.2 (correlation)You do not have to be able to calculate r by hand. You should be able to guess roughly at an r for a swarm of data; as p.101, fig. 2.9, and know and be able to use facts 1 thru 7, p. 100. Also to find r using SPSS.
| Day 11, Hand in on Monday
(repeated from Day 10) 2.2 Correlation (no SPSS) p. 102 2.18 thinking about correlation. 2.19 men two years older 2.20 r =0, strong assoc. (By hand is fine) graph the data (speed on the x-axis). Draw a horizontal line at the mean of the y's (26.8 MPG) and a vertical line at the mean of the x's (40 mph). For each data point, draw a dotted line from the point horizontally to the 40 mph line, and another line vertically to the 26.8MPG line. Use this picture to explain as best you can why the correlation is 0. p. 105 2.26 newspaper 2.27 investment diversification p. 157 2.90 education/age = = = = = = = = = = = = = = = = = = = = Review of straight lines: p. 124, 2.39, 2.40. These will be gone over in class if many people need it. Any MathClinic assistant can help with these. AlsoJust the Basics on reserve covers it. = = = = = = = = = = = = = = = = = = = = = = = Using SPSS to find correl. coeff. Hand in the scatterplots, write the correlation values, other info on your printout. p. 106, 2.28 speed, gas (real) p. 103, 2.23 calories (manual,sec. 0.10 tells how to delete. Save both data files. 2.22 metabolism M/F |
Read, to discuss
p. 99 Use data of 2.17.You graphed this last time. Guess what r is; look in the back of the book to see how close you got. p. 106 2.29 blunders |
Optional
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