MTH136/STA114: Statistics

Homework #9

Due: Wednesday, Apr 4, 2001

  1. DeGroot Chapter 10 Section 1 Page 602 Problems 2, 5, 6 (use S-Plus)
  2. DeGroot Chapter 10 Section 2 Page 611 Problem 11
  3. DeGroot Chapter 10 Section 3 Page 626 Problem 2
The S-Plus source file hw9.q makes S-Plus perform linear regression on DeGroot's Table 10.1 (page 594), with the following results: 

  Call: lm(formula = y ~ x)
  Residuals:
      Min      1Q Median     3Q   Max 
   -2.365 -0.4036 0.3208 0.6613 1.172

  Coefficients:
                Value Std. Error t value Pr(>|t|) 
  (Intercept) -0.7861  0.5418    -1.4509  0.1849 
            x  0.6850  0.1802     3.8008  0.0052 

  Residual standard error: 1.083 on 8 degrees of freedom
  Multiple R-Squared: 0.6436 
  F-statistic: 14.45 on 1 and 8 degrees of freedom, the p-value is 0.005231 

  Correlation of Coefficients:
    (Intercept) 
  x -0.7751
I hope you will find that helpful in doing Exercise 10.2/11 and in showing you what to do for 10.1/6 and 10.3/2. Be sure to look at the function predict.lm() (within S-Plus try typing "?predict.lm" or "help(predict.lm)").