Same chapter3 marksDifficulty: Medium
Find the standard deviation of the first five natural numbers.
Statistics
3 marksDifficulty: Medium
Why is the standard deviation preferred to the mean deviation as a measure of dispersion?
Original Khojo Papers practice question — not from a past board paper.
Answer
The standard deviation squares the deviations, so it uses their sign-free magnitude without the awkward modulus of the mean deviation, and it is algebraically tractable, which makes it usable in further statistical work. It also gives more weight to large deviations, which is usually desirable.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Its unit is the same as that of the observations, unlike the variance.
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