Can a probability measure on $[0,∞)$ with fixed mean have an arbitrarily high variance?

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For $C>0$ arbitrarily large, is it possible to construct a (Borel) probability distribution $\mu$ such that

  1. $\mu$ is supported on $[0,∞),$
  2. $\int_0^∞ \; d\mu(x) = 1,$
  3. $\int_0^∞ x \; d\mu(x) = 1,\qquad$ and
  4. $\int_0^∞ x^2 \; d\mu(x) = C\qquad$?

I suspect it is possible, but my intuition is telling me the opposite—since the worst weighting

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Consider the distribution $\frac{C-1}C\delta_0+\frac1C\delta_C$.