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.
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 Fall '11
 LIN
 Statistics, Standard Deviation, Xi Yi

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