Simulation versus Optimization Methods for Estimation
Topic Outline
Bayesian VS. Frequentist Perspective on Interpretation of Probability
Frequentist: long term frequency of event happening in recurring experiment
Bayesian: a measure of belief in confidence about an event happening
- This belief is based on individuals and different observers may come out different beliefs
- Individuals’ different beliefs do not change what the outcome will come out to be
- You gather evidences to form and update beliefs
- Prior Probability: initial belief $P(A)$
Posterior Probability: updated belief given evidences $P(A X)$
Why Simulation Methods and When
- (1) Simulation versus Asymptotic Assumed Optimization Methods
the latter uses asymptotic assumptions in population properties) for closed-form solutions while the former uses available observed available samples
(2) Concept of Simulation
- you have observed realizations from some target distribution
- you try to build a pseudo-random number generator that mimics the underlying generation process of the observed realization
(3) Types of Simulation
- Resampling: bootstrap, jacknife, permutation
Non-parametric Bayesian versus MCMC
Resampling
Parametric Bootstrap
Bayesian Bootstrap
purpose: estimate distribution for parameter
Example: (1) observed samples: array([ 3.34135494, 4.03678023, 0.4305536 , 4.11717223]), which is actually from exponential(7) (2) plot density (3) need to simulation distribution of mean
Case Studies
Click-through Rate
Reference
(1)[http://www.unc.edu/~carsey/teaching/ICPSR-2011/Sim%20Slides%202%20Handout.pdf]