This Concept introduces students to the some of the measures of spread commonly used, such as range, standard deviation and variance.
Discusses variability and statistical measures that can evaluate the spread of a distribution.
A webpage of basic statistics calculations and worksheets to practice with.
An experiment and explanation are offered as to why n-1 rather than n is used to calculate standard deviation.
The answers to questions about standard deviation. Answers two questions: why a standard deviation takes the square root of the average of the sum of the squared differences between X and X mean, and why n vs n-1 is used in calculations.
A Q&A website answers the question of why n-1 instead of n is used in calculating standard deviation.