SOAN 3120 Chapter Notes -Standard Deviation, Interquartile Range, Box Plot

• School: University of Guelph
• Department: Sociology and Anthropology
• Course: SOAN 3120
• Professor: Michelle Dumas

Document Summary

To get a quick summary of both center and spread, combine all five numbers. The five-number summary if a distribution consists of the smallest observation, the first quartile, the median, the third quartile, and the largest observation, written in order from the smallest to largest. The five-number summary of a distribution leads to a new graph, the boxplot. A boxplot is a graph of the five-number summary. A central box spans the quartiles q1 and q3. A line in the box marks the median m. Lines extend from the box out to the smallest and largest observations. When you look at a boxplot, first locate the median, which marks the center of the distribution. The span of the central box shows the spread of the middle half of the data, and the extremes (smallest and largest observations) show the spread of the entire data set.