Use the median to divide the ordered data set into two halves. The median becomes the second quartile. If there are an odd number of data points in the original ordered data set, do not include the median (the central value in the ordered list) in either half. If there are an even number of data points in the original ordered data set, split this data set exactly in half. The lower quartile value is the median of the lower half of the data. The upper quartile value is the median of the upper half of the data. This rule is employed by the TI-83 calculator boxplot and "1-Var Stats" functions.
Use the median to divide the ordered data set into two halves The median becomes the second quartile If there are an odd number of data points in the original ordered data set do not include the median (the central value in the ordered list) in either half If there are an even number of data points in the original ordered data set split this data set exactly in half The lower quartile value is the median of the lower half of the data The upper quartile value is the median of the upper half of the data This rule is employed by the TI-83 calculator boxplot and "1-Var Stats" functions