Variability is most commonly measured with the following descriptive statistics : Range : the difference between the highest and lowest values Inte...

The standard deviation is the average amount of variability in your data set. It tells you, on average, how far each score lies from the mean . In...

In a normal distribution , data are symmetrically distributed with no skew. Most values cluster around a central region, with values tapering off a...

The empirical rule, or the 68-95-99.7 rule, tells you where most of the values lie in a normal distribution : Around 68% of values are within 1 sta...

Variance is the average squared deviations from the mean, while standard deviation is the square root of this number. Both measures reflect variabi...