Oakland passengers. The Port of Oakland airport reports the number of passengers passing through each month. At first glance, this is just simple growth, but by recognizing the series as a time series, we may learn more.

The following plot was created in Excel.

The increasing spread of the data suggests that a multiplicative model may fit better.
Here’s an exponential trend model with seasonal (monthly)
dummy variables.

d) What components would you now say are in this series?

Transcribed Image Text:

Passengers 1500000 1300000 1100000 900000 700000 500000 300000 0 4 8 Years Since 1990 12 16