Do the correlation coefficient fall ll quickly toward zero

Question

Assignment:

Coast Co Insurance, Inc., is interested in forecasting annual larceny thefts in the United States using the following data:

a. Prepare a time-series plot of these data. On the basis of this graph, do you think there is a trend in the data? Explain.

b. Look at the autocorrelation structure of larceny thefts for lags 1, 2,3, 4, and 5. Do the correlation coefficient fall ll quickly toward zero? Demonstrate that the critical value for r_k is 0.417. Explain what these results tell you about a trend in the data.