C summarize numeric data with numerical summaries including the mean and median measures of center and the range and interquartile range IQR measures of spread and use these summaries to describe the center spread and shape of the data distribution. Box and Whisker Plot. Box and Whisker Plot and Interquartile Range for.
Quartiles are the values that divide a list of numbers into quarters.
The IQR definition given here is widely used but is not the last word in determining whether a given number is an outlier. One definition of outlier is any data point more than 15 interquartile ranges IQRs below the first quartile or above the third quartile. To find the interquartile range we subtract the first quartile from the third quartile. Box and Whisker Plot and Interquartile Range for.