Question 2.132

2.132 Planning for a new product

The editor of a statistics text would like to plan for the next edition. A key variable is the number of pages that will be in the final version. Text files are prepared by the authors using a word processor called LaTeX, and separate files contain figures and tables. For the previous edition of the text, the number of pages in the LaTeX files can easily be determined, as well as the number of pages in the final version of the text. Here are the data:

tpages

Chapter
1 2 3 4 5 6 7 8 9 10 11 12 13
LaTeX
pages
77 73 59 80 45 66 81 45 47 43 31 46 26
Text
pages
99 89 61 82 47 68 87 45 53 50 36 52 19
  1. Plot the data and describe the overall pattern.
  2. Find the equation of the least-squares regression line, and add the line to your plot.
  3. Find the predicted number of pages for the next edition if the number of LaTeX pages for a chapter is 62.
  4. Write a short report for the editor explaining to her how you constructed the regression equation and how she could use it to estimate the number of pages in the next edition of the text.