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A113 Fall Semester 2002 |
Write your name or username here: ________________ Two hours, 40 points. Good luck and do well!
Problem (21 points - one per box)
Consider the formulas for the slope and intercept of the regression line:
and
Use them to compute the slope and intercept of the regression line for the following data:
| |
xi |
yi |
 |
 |
 |
 |
| | 2 | 2 | | | | |
| | 4 | 4 | | | | |
| | 6 | 8 | | | | |
| | 8 | 6 | | | | |
| Sums (if needed) |
| | | |
Then verify your results with this picture.
Feel free to discuss your results, if you want.
Questions (19 points total)
- (3 points) What measures of central tendency have we studied this semester?
- (2 points) What measures of dispersion have we studied this semester?
- (3 points) What does the coefficient of correlation compute?
- (3 points) What is the purpose of the regression line?
- (3 points) What are the differences between the mode, median, and the arithmetic mean?
- (3 points) What does the covariance measure? Where do we use it? How?
- (2 points) What's the difference between the variance and standard deviation?