Using descriptive statistics, you have found out that it takes an average of 40 minutes to complete a mid-term examination in IS
DS 361 A. However, you were surprised to see that the median completion time is 55 minutes. This observation means thata. exam completion time is positively skewedb. exam completion time is negatively skewedc. exam completion time resembles the normal distributiond. exam completion time is probably tri-modal
A data distribution is said to be negatively skewed when <em>median</em> value of the distribution is higher than the <em>average</em> value of the distribution.
In this example
average mid-term completion time is 40 minutes
median mid-term completion time is 55 minutes.
thus median > mean, so the mid-term completion time is negatively skewed. Negatively skewed distributions are also called left-skewed.
