Statistics glossary
Clear, concise definitions of the statistics terms behind our calculators.
Coefficient of variation
The standard deviation relative to the mean, as a percent.
Confidence interval
A range of plausible values for a population parameter.
Kurtosis
A measure of the tailedness of a distribution.
Linear regression
Fitting a straight line to model the relationship between two variables.
Mean
The arithmetic average of a set of numbers.
Median
The middle value of a sorted data set.
Mode
The most frequently occurring value.
Null hypothesis
The default claim of no effect or no difference.
P-value
The probability of a result at least as extreme as observed, under the null hypothesis.
Skewness
A measure of the asymmetry of a distribution.
Standard deviation
The square root of the variance; spread in original units.
Variance
The average of the squared deviations from the mean.