SOAN 3120 Chapter Notes - Chapter 2: Quartile, Box Plot, Standard Deviation

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

Document Summary

The most common measure of spread if the average, or the mean. To find the mean, add their values and divide by the number of observations. Note the formula (n+1)/2 does not give the median just the location of the median in the ordered list. The median unlike the mean is resistant. The outlier just counts as one observation above the center, no matter how far above the center it lies. The mean uses the actual value of each observation and so will chase a single large observation upward. The mean and the median of a roughly symmetric distribution are close together. If the distribution is exactly symmetric, the mean and median are exactly the same. In a skewed distribution, the mean is usually farther out in the long tail than is the median. Many economic variables have distributions that are skewed to the right.