What does the phrase "normal property of a good forecast" imply about bias?

The phrase "normal property of a good forecast" implies that bias should ideally not exist in a well-constructed forecast. In forecasting, bias refers to a systematic deviation from the actual values, which means that forecasts are consistently off in one direction—either overestimating or underestimating demand. A good forecast is expected to be unbiased, reflecting true demand without a tendency to skew in one direction.

The absence of bias in forecasting is essential because it allows for better decision-making regarding resource allocation, inventory levels, and production schedules. If forecasts are unbiased, organizations can trust them to reflect reality and make informed decisions, reducing the risk of issues such as stockouts or excess inventory.

In contrast, other options describe situations that are not ideal for a good forecast. For example, a consistently positive bias would indicate that forecasts overestimate demand, leading to potential waste and inefficiencies. Bias that varies consistently could complicate trend analysis, making it difficult to accurately assess future needs. Lastly, bias may lead to oversupply, as a consistently optimistic forecast can inflate inventory levels, straining resources and increasing costs. Therefore, the ideal state for a good forecast is one where bias does not exist, ensuring accuracy and reliability.