When the Underlying Mean of a Time Series Changes Frequently

question 59

Multiple Choice

When the underlying mean of a time series changes frequently but there is no trend, cyclical, or seasonal influence,

• A) an exponential smoothing forecast with alpha = 0.01 should outperform a exponential smoothing forecast with alpha = 0.30.
• B) a simple moving average forecast with n = 3 should outperform a simple moving average forecast with n = 20.
• C) a simple moving average forecast with n = 20 should perform about the same as a simple moving average forecast with n = 3.
• D) a simple moving average forecast with n = 20 should outperform a simple moving average forecast with n = 3.

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Definitions:

Coxal

Pertaining to the hip or hip joint, often used in the context of bone anatomy to describe the region or aspects of the pelvis.

Fontanel

Soft spots on an infant's skull where the bones have not yet fused, allowing for growth of the brain and skull.

Diaphysis

The shaft or central part of a long bone, which is typically cylindrical in shape and provides leverage and major weight support.

Sinus

A hollow, cavity, or channel within the body, often referring to the air-filled spaces in the skull that open into the nasal cavity.