q12 sa3 Statistics ♒ Name:

Freestyle times 1999-2010 background rectangle major grid lines axes x-axis and y-axis linear regression line data points as circles text layers Freestyle times 1999-2010 Year 0 = 2000 Year Time (s) y-axis labels 29 31 32 34 35 37 39 40 42 43 45 x-axis labels -1.0 0.1 1.2 2.3 3.4 4.5 5.6 6.7 7.8 8.9 10.0

YearTime (s)
-145
042
139
238
336
434
533
632
733
831
930
1029

The table provides data on freestyle swimming times in seconds from 1999 to present for an athlete.

  1. _________ Calculate the sample size n for the data.
  2. _________ Calculate the slope of the linear regression (best fit line).
  3. _________ Calculate the y-intercept of the linear regression (best fit line).
  4. _________ Is the relation between year and time positive, negative, or neutral?
  5. _________ Calculate the linear correlation coefficient r for the data.
  6. ______________ Is the correlation none, weak/low, moderate, strong/high, or perfect?
  7. ______________ Determine the coefficient of determination.
  8. ______________ What percent in the variation in year "explains" the variation in time?
  9. _________ Use the slope and intercept to predict the time for the athlete in year 11.
  10. _________ Use the slope and intercept to determine the year in which the athlete is predicted to achieve a time of 23 seconds.