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Table of Contents



Software Output

Raw data from previous example 

Descriptive Statistics

Variable: Age
Count 7 Pop Var 215.6327 B
Sum 310 Sam Var 251.5714
Mean 44.2857 Pop Std 14.6844
Median 42 Sam Std 15.861
Min 24 Std Error 5.9949
Max 65 CV% 35.8152 C
Range 41 95% CI (+/-) 14.669 D
Skewness 0.0871


One sample t-test (P<) 0.0003 E



A   Skewness provides an indication of the how asymmetric the distribution is for a given sample.  A negative value indicates a negative skew.  Values greater than 1 or less than -1 indicate a non-normal distribution.    

B   Population variance and standard deviation (Std) will always be less than sample variance and standard deviation, since you are dividing the sum of squares by n instead of n-1.

C   Coefficient of Variation (CV) is the ratio of the sample standard deviation to the sample mean: (sample standard deviation/sample mean)*100 to calcuate CV%.  It is used as a measure of relative variability, CV is not affected by the units of a variable. 

D   Add and subtract this value to the mean to create a 95% confidence interval.

E   This represents the results of a one-sample t-test that compares the sample mean to a hypothesized population value of 0 years of age. In this example, the sample mean age of 44 is statistically significantly different from zero.



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