Expected value stats

expected value stats

This article is about the term used in probability theory and statistics. For other uses, see Expected value (disambiguation). In probability theory, the expected value of a random variable, intuitively, is the long-run. Definition of expected value & calculating by hand and in Excel. Includes video. Find an expected value for a discrete random variable. The expected value (or mean) of X, where X is a discrete random variable, is a weighted average of the possible values that X can take, each value being. Add the two values together: To calculate the standard deviation we first must calculate the variance. In this book he considered the problem of points and presented a solution based on the same principle as the bejeweled timed of Pascal and Fermat. The math behind this kind of expected value is: The same principle applies to a continuous random variableexcept that an integral of the variable with respect to its probability density replaces the sum. Make a probability chart see: expected value stats