Exponential moving average (EMA), or exponentially weighted moving average (EWMA), applies a damping factor, alpha, that exponentially decreases the weights of older values. This technique gives much more weight to recent observations, while retaining older observations.
- Compute the arithmetic average of the first n rows.
The value n is specified by the StartRows syntax element.
- For each subsequent row, compute the new exponential moving average value with this formula:
EMAM = alpha * V + (1 - alpha) * EMAM-1
The value alpha is specified by the Alpha syntax element. V is the new value.