Homework 5


due in class, Tuesday February 22



Include only the most relevant parts of output from R (or whatever package you are using). Do not include a transcript of your entire session, just cut and paste (electronically or literally) the necessary parts. Please staple your assignment if it is more than one page.

Required problems:

1) 10.91 (p. 376) just compare (i.e. test for a difference) price between domestic and imports - note that the first numerical column is price, and the last column is 1 for a domestic and 0 for an import
2) 11.5 (p. 401)
3) 13.6 (p. 493) Use a computer package (preferably R) for part (b).
4) 13.17 (p. 498)
5) Show that if the slope (b1) is known and only the intercept (b0) is to be fitted, the least squares fit for b0 is b0-hat = Y-bar - b1*X-bar. (To do this, you need to differentiate the sum of squared errors (residuals) with respect to b0, set it equal to 0, and solve for b0-hat.)

Optional problem:

6) 13.70 parts (a)-(c), (e)-(f) (pp. 532-3)

If you have the 8th edition, the corresponding problems are:
1) 10.70 (p. 381), 2) 11.5 (p. 405), 3) 13.6 (p. 497), 4) 13.17 (p. 503), 5) (above), 6) 13.68 (p. 539)