Q.Which method of finding trend is best to eliminate the effect of repetitive short-term variations?

The moving average method smooths out repetitive short-time variations.

When we take moving averages, the short-period upward and downward fluctuations tend to cancel one another within each average, so the smoothed series reflects mainly the trend. Hence the method of moving average is best suited to eliminate the effect of repetitive short-time …

The moving-average method is best for eliminating repetitive short-term (seasonal/short-period) variations, because averaging successive groups cancels them out.

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