Introduction to Probability

• An experiment is a controlled operation that yields a set of results.
• The possible results of an experiment are called outcomes
• An event is a subset of the outcomes of an experiment.
• There are two types of probability that we consider in this chapter
  • Empirical probability is calculated by performing an experiment a number of times and counting the number of times an outcome in the event occurs.
  • Theoretical probability is determined by studying all possible outcomes that can occur for a given experiment.
• For an event E, P(E) means the probability that event E occurs, or Probability of E.
• For empirical probability P(E) = number of outcomes in E/number of trials.
• The Law of Large Numbers states that probability statements apply in practice to a large number of trials, not to a single trial. It is the relative frequency over the long run that is accurately predictable, not individual events or precise totals.
• Do some problems page 680