Probability Basics
Build intuition for chance and uncertainty.
Bayes' Theorem
a formula that describes how to update the probability of a hypothesis as more evidence becomes available
combination
a selection of objects where the order does not matter
odds
the ratio of the probability of success to the probability of failure
simple event
an event that has only one outcome
random
a process where each outcome has an equal chance of occurring
relative frequency
the fraction of times an answer occurs in a data set
compound event
an event consisting of two or more simple events
expected value
the average outcome of an experiment over many repetitions
fair game
a game where the expected value of the profit is zero
tree diagram
a visual tool showing all possible outcomes of a sequence of events
permutation
an arrangement of objects where the order matters
experimental probability
ratio of successful trials to total trials conducted
dependent events
the outcome of one event affects the probability of another
law of large numbers
experimental results approach theoretical probability as trials increase
conditional probability
probability of an event given that another event has occurred
outcome
a single possible result of a probability experiment
100% probability
certain event
sample space
the set of all possible outcomes
mutually exclusive events
events that cannot happen at the same time
theoretical probability
favorable outcomes divided by total outcomes
complementary event
the probability of an event not occurring
independent events
one outcome does not change the odds of the other
50% probability
even chance
0% probability
impossible event