Probability: Difference between revisions

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: <math>(g(X_n) - g(\theta)) \approx g'(\theta)(X_n - \theta)</math>
: <math>(g(X_n) - g(\theta)) \approx g'(\theta)(X_n - \theta)</math>


==Limit Theorems==
==Inequalities and Limit Theorems==
===Markov's Inequality===
===Markov's Inequality===
Let <math>X</math> be a non-negative random variable.<br>
Then <math>P(X \geq a) \leq \frac{E(X)}{a}</math>
{{hidden | Proof |
<math>
E(X)
= \int_{0}^{\infty}xf(x)dx
= \int_{0}^{a}xf(x)dx + \int_{a}^{\infty}xf(x)dx
\geq \int_{a}^{\infty}xf(x)dx
\geq \int_{a}^{\infty}af(x)dx
=a \int_{a}^{\infty}f(x)dx
=a*P(X \geq a)\\
\implies P(x\geq a) \leq \frac{E(X)}{a}
</math>
}}
===Chebyshev's Inequality===
===Chebyshev's Inequality===
* <math>P(|X - \mu| \geq k \sigma) \leq \frac{1}{k^2}</math>
* <math>P(|X - \mu| \geq k \sigma) \leq \frac{1}{k^2}</math>