Russel-Research-Method-in-Anthropology

Univariate Analysis 575
some basic shapes of distributions: skewed to the right, skewed to the left,
bimodal, and normal. I have shown them again in figure 19.4, but this time
notice the mode, the median, and the mean:
1. the mode, the median, and the mean are the same in the normal distribution;
2. the mean is pulled to the left of the median in negatively skewed distributions;
3. the mean is pulled to the right of the median in positively skewed distributions;
and
4. some distributions are bimodal, or even multimodal. In these cases, you need to
calculate two or more means and medians because the global mean and median
give you a distorted understanding of the distribution.
Figure 19.4. Some basic types of distributions.