Math 1431 – Spring 2003 – Test #1 – Practice
Question 9 Answer
The scatterplot is:
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- There does not seem to be any outliers. The pattern looks linear and this linear relationship seems
to be relatively strong. The variables are negatively–associated.
- The correlation coefficient, r = –0.949.
- The least–regression line is
= –0.41 x + 1025.9. Thus,
the predicted winning time for 2020 is
= –0.41 (2020) + 1025.9 = 196.3.
The prediction is not very good because 2020 is far away from the data.
NOTE: The winning time for 2000 was 212.1!