Question
Show that$$\lim _{n \rightarrow \infty} e^{-n} \sum_{k=0}^{n} \frac{n^{k}}{k !}=\frac{1}{2}$$by applying the central limit theorem to suitably chosen, independent, Poisson distributed random variables.
Step 1
The term \( \sum_{k=0}^{n} \frac{n^{k}}{k!} \) represents the cumulative distribution function (CDF) of a Poisson random variable \( X \) with parameter \( n \). Specifically, \( X \sim \text{Poisson}(n) \) means that \( P(X = k) = \frac{n^k e^{-n}}{k!} \). Show more…
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