In a three-day moving average forecast, which data points are used to forecast the next day?

In a three-day moving average forecast, which data points are used to forecast the next day?

• A. The most recent three days
• B. The oldest three days
• C. The most recent two days
• D. All days in history

Answer: (A)

The main idea is that a three-day moving average uses a fixed window of the most recent data to form the forecast. For a three-day moving average, you take the three most recent actual observations, average them, and use that average as the forecast for the next day. This approach captures the latest trend while smoothing out short-term fluctuations. Using the three most recent days keeps the forecast responsive to recent changes without being swayed by data from too far in the past. If you used data that are older than three days, you’d dilute the current pattern and lose the benefit of the moving-average smoothing. If you used only the oldest three days, you’d ignore new information. If you used only the most recent two days, that would be a two-day moving average, not a three-day one. Including all days in history isn’t how a moving average is defined for a fixed window. So, the forecast for the next day is the average of the three most recent days.

The main idea is that a three-day moving average uses a fixed window of the most recent data to form the forecast. For a three-day moving average, you take the three most recent actual observations, average them, and use that average as the forecast for the next day. This approach captures the latest trend while smoothing out short-term fluctuations.

Using the three most recent days keeps the forecast responsive to recent changes without being swayed by data from too far in the past. If you used data that are older than three days, you’d dilute the current pattern and lose the benefit of the moving-average smoothing. If you used only the oldest three days, you’d ignore new information. If you used only the most recent two days, that would be a two-day moving average, not a three-day one. Including all days in history isn’t how a moving average is defined for a fixed window.

So, the forecast for the next day is the average of the three most recent days.