Spread vs Center Statistics Example 2

Follow the full solution, then compare it with the other examples linked below.

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Dataset A: {10, 10, 10, 10, 10}. Dataset B: {2, 6, 10, 14, 18}. Compare their centres and spreads.

1
Step 1: Mean of A = 10, Mean of B = $\frac{2+6+10+14+18}{5} = 10$ . Same centre.
2
Step 2: Range of A = 0 (no spread). Range of B = $18 - 2 = 16$ .
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Step 3: A has zero variability; B is spread out symmetrically around 10.

Answer

Both have mean 10, but A has range 0 and B has range 16.

Two datasets can share the same centre but differ dramatically in spread. Reporting only the mean hides important information about variability.

About Spread vs Center

Center describes where the 'middle' of data lies; spread describes how far data extends from that center.

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