Question: Explain why we should not use the regression equation we found in Exercise for speed-skating time versus year to predict the winning time for the 2010 Winter Olympics.
Exercise: We examined a picture of winning time in men's 500-meter speed skating plotted across time. The data represented in the plot started in 1924 and went through 2002. A regression equation relating winning time and year for 1924 to 1998 is
winning time = 264.5 - (0.1142)(year)
a. Would the correlation between winning time and year be positive or negative? Explain.
b. In 2002, the actual winning time for the gold medal was 34.42 seconds. Use the regression equation to predict the winning time for 2002, and compare the prediction to what actually happened.
c. Explain what the slope of - 0.1142 indicates in terms of how winning times change from year to year.
d. The Olympics are held every four years. Explain what the slope of - 0.1142 indicates in terms of how winning times should change from one Olympics to the next.