A Measure of central tendency is a measure that describes the middle or center point of a distribution. A good measure of central tendency is representative of the distribution.
The Mean (average) is the best measure of central tendency when the distribution is normal
In a negatively skewed distribution, the median will be a little bit greater than the mean and in a positive skewed distribution, the median will be a little bit lower than the mean.
With the following Scores: 2 7 8:
The better measure of your performance is the median.
The mean and median are so different because there is one score that is extremely different from the rest. In statistics, such extreme values are called outliers
The mean is affected by the presence of an outlier; however, the median is not.
A statistic that is not affected by outliers is called resistant.
The median is a resistant measure of center, and the mean is not resistant.
As a result, when we have a data set that contains an outliers, it is better to use the median to describe the center, rather than the mean.