The mean (arithmetic) issimply the sum of the numbers divided by the number of numbers. The median is the midpoint of a distribution: the same number of scores is above the median as below it. The mode is the most frequently occurring value.
Although all are great in depicting a type of “middle” value, each can skew the overall depiction of results.When a distribution is symmetric, then the mean and the median and usually mode are the same and using either can be appropriate to use. The reading the professor provided tells us to consider the following distribution: 1, 3, 4, 5, 6, 7, 9. The mean and median are both 5. The mean, median, and mode are identical in the bell-shaped normal distribution. However, when the distribution is not symmetric, the mean, median, and mode may not depict an accurate “average” or “middle ground”. While the mean may be one number, there can be many more on one side of the middle with the “central distribution” being a bit “off”.
Online Statistics Education: An Interactive Multimedia Course of Study Developed by Rice University (Lead Developer), University of Houston Clear Lake, and Tufts University