Overview
Measures of variation are essential tools in statistics that help us understand the spread of data. They include range, variance, standard deviation, and interquartile range, each providing unique insights into how data points differ from one another. Understanding these measures allows us to make i...
Key Terms
Example: In the data set {3, 7, 5}, the range is 7 - 3 = 4.
Example: If the mean is 5 and the values are {3, 5, 7}, the variance is 2.
Example: A standard deviation of 2 means most values are within 2 units of the mean.
Example: For the data set {1, 3, 5, 7, 9}, Q1 is 3 and Q3 is 7, so IQR = 7 - 3 = 4.
Example: In the set {1, 2, 2, 3, 100}, 100 is an outlier.
Example: The mean of {2, 4, 6} is (2+4+6)/3 = 4.