Math 151 , Spring 2005, Day 17 Wed. March 9 Hit reload

Day 18 (Wed. Mar 9): Reading: Read D&V Ch8 & Ch9(all), Do AS8 Regression. (AS9, lightly)
Ahead, we'll skip Ch 10, do Ch11 very lightly, then  12&13
Hand in Monday
(D&V Ch.8  p.152 ff)
25&27 Burgers (type the data into SPSS)
19 SAT scores (You did 17 Day 15.  Look in the answers in the back of the book for the formula you calculated which you need for part e.)

Chapter 9:  D&V p. 174ff. unless otherwise noted:
1,3 Marriage age (Type your data into SPSS.  Your answers may vary. Cf.#13p.73)
2 Age difference
15, 16 Gestation  (note, these are summarized data)
20 Life expectancy (SPSS)(again, summarized data)  For b, if an outlier is "impossible", delete it!
18 Smoking. (SPSS) Graph it and discuss what you might do to model it; don't DO it.

Groups, from ActivStats Ch7 HW (same datasets you used before, different questions)
A) Metabolic rate (MRA-81-4) on Lean Body Mass.  i) Make a scatterplot with the regression lines for the 2 sexes and the whole group.  (a graph with Panel variable Sex is good in addition).  The R2 for Males is quite low, compared to that for Females, and compared to that for the whole group.  ii) Explain how the scatter that you see for the two groups is consistent with their different  R2's.  iii) How can it be that the more scattered Males  added on to the Females  end up  producing an R2 close to that of the Females alone?
B) Bear neck/weight (TRE-58-26)  i) Make a single scatterplot with the regression lines for the 2 sexes.  (Get rid of the Total line)  ii) Then do a graph with Panel variable Sex and regression lines, better to see them separately.  iii) Describe any bears which are outliers and/or  influential points, and any ways in which the data are not well modeled by the straight lines. 

Read,
to discuss

Ch.9
p. 176:
11, 12, 13, 14 
(all about outliers)

7a-d Reading

Op-
tion-
al 
HW, questions?  Day 17
A. Income depends on height?! Read the article and answer this.
  a)What is "$789", and what kind of analysis did they do?
  b)What does my footnote at the end tell you about the data that the article did not?
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Pick a digit (from 0,1,2,3,4,5,6,7,8,9).  Write it down.   Keep it for next time.
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

Regression line: D&V Ch 8&9, AS8&9, "Regressing y ON x" Formula yhat =  b0 + b1 x
Work today: Continue with Day 17.    End of Part II
 ==== = = = = = = = =


Sievers home  Math151-Sp05/Days18.htm 1:30pm 3/9/05
This page belongs to Sally Sievers who is solely responsible for its content. Please see our statement of responsibility.