Graphical Summary
Table of Statistics - Mean and N
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Graphical SummaryTable of Statistics - Mean and N |
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The mean (also called the average) is a measure of where the center of your distribution lies. It is simply the sum of all observations divided by the number of observations. The mean is strongly influenced by extreme values.
N is the number of non-missing values in the data set
Example Output |
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Anderson-Darling Normality Test A-Squared: 0.99 P-Value: 0.008
Mean 3.6364 StDev 2.3779 Variance 5.6545 Skewness 2.11078 Kurtosis 5.61936 N 11
Minimum 1.0000 1st Quartile 2.0000 Median 3.0000 3rd Quartile 4.0000 Maximum 10.0000
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The mean and N values are listed in the middle right of the Graphical Summary.
Interpretation |
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For the precipitation data, N = 11 and the mean is:
(2 + 3 + 10 + 5 + 4 + 4 + 3 + 3 + 1 + 2 + 3) / 11 = 3.6364.
Even though most months (7 out of 11) had 3 days or less of precipitation, the mean is close to 4. The extreme value of 10 days with precipitation for April is affecting the mean quite a bit. Without this observation, the mean would be exactly 3. On the other hand, if you include an April with 30 days of rain instead of 10 in the calculations, the mean would be 5.455, a value that is greater than all but one observation!
