# Appendix: Introduction to Statistics

Given that much of the debate surrounding intelligence is based on
statistical analysis, this outline is inserted by way of being a basic
primer for those interested.
*Statistics* is
a branch of mathematics dealing with the collection, analysis and interpretation
of data, which allows the data to be organised and presented in a way
that helps facilitate a better understanding of any patterns in the
data. In this context, statistics has developed two methodologies, i.e.
*descriptive*
and
*inferential*, that first attempts to summarize the data using techniques like standard
deviation and then, second, to draw conclusions about the nature of
the data. However, the scope of this discussion is only intended to
be a brief introduction in support of the wider discussion of IQ and
its social implications.

## Frequency Distribution

A
*frequency distribution* may simply be described as a table listing
each value of some variable and the number of times it occurs in a given
dataset. We might introduce the idea of a frequency distribution by
way of an example of *‘height’* within some given population.

If the people were lined up in order of height, we might expect that the line would take the shape of a distribution, if those of the same height stood in rows as illustrated right. While we might readily see a distribution pattern in the diagram, it does not necessarily help us to quantify the variation in the data. However, this then requires the introduction of two other discussions: