What does "modal" mean?
There are several characteristic values of a set of sample values commonly used to describe, simplistically, the set as a whole. The most common is the mean, or average value. A second common one is the peak value, and a third is the mode. The mode is that value which occurs most often. It usually comes to the fore when the sample values in the set must be integers, and tend to be close to a central value, as is the case with yDNA marker values. Let's consider five possible sets of marker values.
|Marker set||Marker values||Mean||Mode|
|1||29, 29, 29, 29, 30||29.17||29|
|2||18, 19, 19, 19||18.75||19|
|3||12, 11, 12||11.67||12|
|4||15, 16, 16||15.67||16|