Which of the following statements regarding components of a time series are true? (Check all that apply.)
Answer
1. Trend is a constant or steady increase or decrease in the data/measurements over time.
2. Cyclical variation is gradual movement around the trend line that is always attributable (caused by) the business cycle and economic conditions.
3. Seasonal variation is unpredictable increases and decreases that occur within a calendar year.
4. Irregularity is what is left after taking into account Trend, Cyclical, and Seasonal behavior. It has no observable patterns. It is random.