Simply Statistics

Sample Spaces: A sample space is simply all of the possible outcomes of an experiment.

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Probability Rules:

The subtraction rule- The probability that an event A will occur is one minus the probability that event A does not occur.

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The multiplication rule- The probability that both A and B occur is equivalent to the probability that A occurs times the probability of B occurring given that A has already occurred.

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The addition rule- The probability that event A or event B occur is equivalent to the probability that A occurs plus the probability that B occurs minus the probability that A and b occurs.

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Complementary Events: Events that only have two possible outcomes, either event A happens or event B happens.

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The Binomial Distribution: This follows from an experiment that consists of n trials, where each outcome is equally likely, and there are only two possible outcomes, and the probability of success is the same for every trial. The mean is equivalent to n*p, the variance is n*p*(1-p), and the standard deviation is the square root of the variance.

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Expected Value- This is just a weighted mean of all the different components that make up a distribution.