(Maximum A-Posteriori Estimation (MAP))
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<math>\hat{y}_{\rm MMSE}(x) = \int\limits_{-\infty}^{\infty}\ {y}{f}_{\rm Y|X}(y|x)\, dy={E}(Y|X=x)</math>
 
<math>\hat{y}_{\rm MMSE}(x) = \int\limits_{-\infty}^{\infty}\ {y}{f}_{\rm Y|X}(y|x)\, dy={E}(Y|X=x)</math>
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 +
'''Law Of Iterated Expectation'''
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Unconditional Expectaion--E[X] = E{E[x|0theta]}
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                                      |
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                  (conditional expectation of function theta) functio                               
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Mean square error : <math>MSE = E[(\theta - \hat \theta(x))^2]</math>
 
Mean square error : <math>MSE = E[(\theta - \hat \theta(x))^2]</math>

Revision as of 11:04, 13 December 2008

Maximum Likelihood Estimation (ML)

$ \hat a_{ML} = \text{max}_a ( f_{X}(x_i;a)) $ continuous

$ \hat a_{ML} = \text{max}_a ( Pr(x_i;a)) $ discrete

Maximum A-Posteriori Estimation (MAP)

$ \hat \theta_{MAP}(x) = \text{arg max}_\theta P_{X|\theta}(x|\theta)P_ {\theta}(\theta) $

$ \hat \theta_{MAP}(x) = \text{arg max}_\theta f_{X|\theta}(x|\theta)P_ {\theta}(\theta) $

Minimum Mean-Square Estimation (MMSE)

$ \hat{y}_{\rm MMSE}(x) = \int\limits_{-\infty}^{\infty}\ {y}{f}_{\rm Y|X}(y|x)\, dy={E}(Y|X=x) $

Law Of Iterated Expectation

Unconditional Expectaion--E[X] = E{E[x|0theta]}

                                      |
                 (conditional expectation of function theta) functio                                


Mean square error : $ MSE = E[(\theta - \hat \theta(x))^2] $

Linear Minimum Mean-Square Estimation (LMMSE)

$ \hat{y}_{\rm LMMSE}(x) = E[\theta]+\frac{COV(x,\theta)}{Var(x)}*(x-E[x]) $

Hypothesis Testing: ML Rule

Given a value of X, we will say H1 is true if X is in region R, else will will say H0 is true.

Type I error

Say H1 when truth is H0. Probability of this is: Pr(Say H1|H0) = Pr(X is in R|theta0)

Type II error

Say H0 when truth is H1. Probability of this is: Pr(Say H0|H1) = Pr(X is NOT in R|theta1)

Hypothesis Testing: MAP Rule

Overall P(err) = $ P_{\theta}(\theta_{0})Pr[Say H_{1}|H_{0}]+P_{\theta}(\theta_{1})Pr[Say H_{0}|H_{1}] $

Alumni Liaison

has a message for current ECE438 students.

Sean Hu, ECE PhD 2009