- Probability can either be interpreted as a long-run frequency (Frequentist) or a measure of belief and uncertainty (Bayesian)
- Bayes’ Rule is a good framework for many things. Update conjectures based on supporting evidence that is likely observed.
- The hyperparameters of a model refer to the parameters of the distribution of the priors (from a Bayesian Perspective). The hyperparameters encode our beliefs about the distribution.
Central Limit Theorem
- Assumption: We have
random variables that are independent and identically distributed each with mean and . - The Central Limit Theorem states that as
, then the distribution of the sum approaches the Normal Distribution. - Another way to say this is that the sampling distribution tends towards the normal distribution for a large number of samples even if the original variables are not normally distributed.
- The implication is that analysis using normal distributions are usually sufficient since many distributions tend to this in the limit.
Monte Carlo Simulation
- Monte Carlo is one approach to approximating a function of a random variable. This is done by approximating the probability distribution of the function by taking many samples and then taking the empirical probability distribution.
- More formally, it approximates
Where
. - By the Central Limit Theorem, the above approximation becomes better with more samples. This can be quantified using the standard error computed as
Topics
- Fundamental Constructs of Probability Theory
- Random Variables and Probability Distributions
- Probability Distributions Zoo - more on probability distributions and what they are measuring
- Queueing Theory
- Measure Theory - a more formal treatment of probabilities
- Markov Chain
- Probabilistic Graphical Models
Links
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Calculus - more on calculus, relevant for integrals and derivatives.