Z scores transform data. Taking data and converting it to standard deviation. regular: reverse: z score = [ score - mean ] / standard deviation score = [ z score * mean ] + score The mean of a curve always has a z score of zero. On a chart if the z scores are on the same side of the mean, subtract && if on different side of means, add. mean = 0 standard deviation = 1 A statistic is a number that summarizes, defines, or makes understandable a set of numbers or data. A strong correlation means you expect a usual response from doing a given act. Like switching a light on. Switch on, the light turns on. Foward = you get the mean, standard deviation, and a score. Reverse = you are given a percentage. Range of values: -1.0 to 1.0 |r| = 1 , perfect correlation -0.7 < |r| > 0.7 strong correlation Slope goes up = postive correlation Slope goes down = negative correlation Points go along the line = perfect correlation When things move in the same direction - Positive Correlation Make more money, get more cars. o
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This note was uploaded on 10/06/2011 for the course MATH 3400 taught by Professor Lin during the Fall '11 term at CUNY Brooklyn.