- •Distribution Overview
- •Discrete Distributions
- •Continuous Distributions
- •Probability Theory
- •Random Variables
- •Transformations
- •Expectation
- •Variance
- •Inequalities
- •Distribution Relationships
- •Probability and Moment Generating Functions
- •Multivariate Distributions
- •Standard Bivariate Normal
- •Bivariate Normal
- •Multivariate Normal
- •Convergence
- •Statistical Inference
- •Point Estimation
- •Empirical distribution
- •Statistical Functionals
- •Parametric Inference
- •Method of Moments
- •Maximum Likelihood
- •Delta Method
- •Multiparameter Models
- •Multiparameter delta method
- •Parametric Bootstrap
- •Hypothesis Testing
- •Bayesian Inference
- •Credible Intervals
- •Function of parameters
- •Priors
- •Conjugate Priors
- •Bayesian Testing
- •Exponential Family
- •Sampling Methods
- •The Bootstrap
- •Rejection Sampling
- •Importance Sampling
- •Decision Theory
- •Risk
- •Admissibility
- •Bayes Rule
- •Minimax Rules
- •Linear Regression
- •Simple Linear Regression
- •Prediction
- •Multiple Regression
- •Model Selection
- •Non-parametric Function Estimation
- •Density Estimation
- •Histograms
- •Kernel Density Estimator (KDE)
- •Smoothing Using Orthogonal Functions
- •Stochastic Processes
- •Markov Chains
- •Poisson Processes
- •Time Series
- •Stationary Time Series
- •Estimation of Correlation
- •Detrending
- •ARIMA models
- •Causality and Invertibility
- •Spectral Analysis
- •Math
- •Gamma Function
- •Beta Function
- •Series
- •Combinatorics
4. |
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In quadratic mean (L2): Xn ! X |
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Relationships |
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n!1 E |
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Xn ! X |
^ (9c 2 R) P [X = c] = 1 =) Xn ! X |
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Xn ! X |
^ Yn ! Y =) XnYn ! XY |
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PP
Xn ! X =) '(Xn) ! '(X)
DD
Xn ! X =) '(Xn) ! '(X)
qm
Xn ! b () limn!1 E [Xn] = b ^ limn!1 V [Xn] = 0
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X1; : : : ; Xn iid ^ E [X] = ^ V [X] < 1 () Xn !
Slutzky's Theorem
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Xn ! X and Yn ! c =) Xn + Yn ! X + c
D P D
Xn ! X and Yn ! c =) XnYn ! cX
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In general: Xn ! X and Yn ! Y =6) Xn + Yn ! X + Y
10.1Law of Large Numbers (LLN)
Let fX1; : : : ; Xng be a sequence of iid rv's, E [X1] = .
Weak (WLLN)
P
Xn ! n ! 1
Strong (SLLN)
as
Xn ! n ! 1
10.2Central Limit Theorem (CLT)
Let fX1; : : : ; Xng be a sequence of iid rv's, E [X1] = , and V [X1] = 2.
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Z := |
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nlim |
P [Zn z] = (z) |
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where Z N (0; 1)
z 2 R
CLT notations |
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Zn N (0; 1) |
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Continuity correction |
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Delta method |
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Yn N ; |
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n |
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11 Statistical Inference
iid
Let X1; ; Xn F if not otherwise noted.
11.1Point Estimation
Point estimator bn of is a rv: bn = g(X1; : : : ; Xn) |
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bias( n) = E n |
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Consistency: |
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Sampling |
distribution: F ( |
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Standard error: se( n) = |
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error: mse = |
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Mean squared |
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normality: |
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Slutzky's Theorem often lets us replace se(bn) by some (weakly) consistent estimator bn.
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