Question 13.29

13.29 Hourly earnings.

Consider monthly data on the hourly earnings of production and nonsupervisory employees in private U.S. industry, beginning in January 2010 and ending in July 2014.18

earn

  1. Make a time plot of these data. Describe the overall movement of the data series.
  2. Does this time series exhibit a trend? If so, describe the trend.
  3. Do these data exhibit a regular, repeating pattern (seasonal variation)? If so, describe the repeating pattern.

13.29

(a) Earning is increasing over time. (b) Yes, there is a trend; earning is increasing over time. (c) It is hard to discern a seasonal pattern, though earning seems to be somewhat stable at times and then starts to climb rapidly during other times.