Oakland outlier. The plot of residuals in Exercise 41 shows an outlier that wasn’t as evident in the data. The outlier is September 2001. Clearly, this wasn’t a typical month for air travel. Here are three models fit to this series, a single exponential smooth, a 12-point moving average, and the fitted values from the seasonal regression model of Exercise 41.

Discuss how each deals with the outlier.

The remaining exercises require the use of statistics software.
Statistics packages vary in their capabilities and in the default decisions that some make. As a result, depending upon which package you choose, your answers may differ from those in the back of the book.

Transcribed Image Text:

Passengers Passengers Passengers 1,500,000+ 1,250,000- 1,000,000+ 750,000+ 500,000 H 1 20 40 60 80 100 120 140 160 180 Month (Jan 1990-1) Vartable Smoothing Constant Accuracy Measures Actual Alpha 0.5 MAPE 8 Fits MAD 66412 Forecasts MSD 6969905066 95.0% Pl 1,500,000- 1,250,000+ 1,000,000+ 750,000- 500,000+ 444 1 20 40 60 80 100 120 140 160 180 Month (Jan 1990 = 1) Variable Moving Average Accuracy Measures Actual Length 12 MAPE 8 Fts MAD 68231 Forecasts MSD 8705890030 96.0% Pl 1,250,000 1,000,000 750,000- 500,000 40 80 + + 120 160 Month (Jan 1990 = 1)