Skewness is asymmetry in a statistical distribution, in which the curve appears distorted or skewed either to the left or to the right. Skewness can be quantified to define the extent to which a distribution differs from a normal distribution. This situation is also called negative skewness.
In this way, what does it mean to be skewed left?
For a right skewed distribution, the mean is typically greater than the median. Also notice that the tail of the distribution on the right hand (positive) side is longer than on the left hand side.
What is a positively skewed distribution?
A distribution is negatively skewed, or skewed to the left, if the scores fall toward the higher side of the scale and there are very few low scores. In positively skewed distributions, the mean is usually greater than the median, which is always greater than the mode.
How does skew affect mean and median?
Five of the numbers are less than 2.5, and five are greater. Notice that in this example, the mean is greater than the median. This is common for a distribution that is skewed to the right (that is, bunched up toward the left and with a "tail" stretching toward the right).