Probability and Distribution

Probability

Conditional Probability

Probability Distribution

• a function mapping an event to a probability

• example

  • f(x): distribution
  • x: event
    

• PDF, CDF
  

Normal Distribution

• very commonly observed distribution
  • continuous numeric value
• long tail

Beta Distribution

• supports a closed interval
• continuous numeric value
• [0, 1]
  • very nice characteristic
    => matches up the characteristics of probs

Binomial Distribution

• simplest distribution for discrete values
  • Bernoulli trial, yes or no
  • 0 or 1

Multinomial Distribution

• The generalization of the binomial distribution
  • Beyond yes/no
  • Choose a,b,c,d, ....
  • Word selection, cluster selection