What is the final step to be performed when computing Σ(X - 2)2?

What is the final step to be performed when computing Σ(X - 2)2?

• A. Square each value
• B. Subtract 2 points from each score
• C. Sum the squared values
• D. Subtract 22 from each X2 value

Answer: (C)

This is about summing squared deviations from 2. For each observation X, you subtract 2 to get the deviation, then square that deviation. After you have all the squared deviations, you add them up to form the final sum. That aggregation step—adding the squared values—is what the expression Σ(X−2)² is doing. If you square X directly or just subtract 2 without squaring and summing, you wouldn’t be computing the same quantity. So the final step is to sum the squared values.

This is about summing squared deviations from 2. For each observation X, you subtract 2 to get the deviation, then square that deviation. After you have all the squared deviations, you add them up to form the final sum. That aggregation step—adding the squared values—is what the expression Σ(X−2)² is doing. If you square X directly or just subtract 2 without squaring and summing, you wouldn’t be computing the same quantity. So the final step is to sum the squared values.