STAT 1430 Lecture Notes - Lecture 14: Random Variable, Gm Family 0 Engine, Weighted Arithmetic Mean

• School: Ohio State University
• Department: Statistics
• Course: STAT 1430
• Professor: Judit Bach

Document Summary

The mean of a discrete random variable: a weighted average of the possible outcomes; weights are the probabilities. Possible outcomes: x1, x2, xk call them x. Probabilities: p1, p2, pk call them p(x: notation: , formula: ! The mean of a discrete random variable: average of all possible values in whole population and the overall expected value of x. Average family size for the entire population. Rules of means #1 linear transformations: linear transformation: Multiply x by constant and/or add a constant: example: A x+b = y = a x + b. Y = 1. 10 x + 500: note: this rule holds for any x, y. Example: cancun temperatures: the mean temperature in cancun is 28. 5 degrees centigrade ( c). What is the mean temperature in fahrenheit (f): f=9/5 c + 32. Example: 0 degrees c = 32 degrees f: mean of f = ! Rule #2 of means sums and differences: rule: 2 random variables x and y.