Title: Common statistical notation
Course: UGQuants (SSPS) > Section: Maths Self Test

Common statistical notation

Even quite basic quantitative analysis can sometimes use a language of signs and symbols that is baffling to the uninitiated. Most of these can only really be explained and understood effectively when discussed in the context of their use, and so in the course we will generally explain such symbols as we go along. However, listed below are some very common usages which are worth knowing from an early stage:

Sign | Meaning
x and y | Commonly used to represent variables, sometimes with x as the independent variable and y as the dependent variable. Also used to describe the axes of a graph: the horizontal line at the bottom is known as the x-axis and the vertical line to the left is the y-axis
∑ | The sum of. In a formula or equation this indicates that you need to add together all the elements related to this sign
N or n | Used to represent the number of cases in a population, sample, or sub-group. Conventionally, N is often used to indicate the size of a population and n to indicate the size of a sample.
P or p | Used to indicate the probability of a given outcome etc. Also used for the closely related concept of proportion. Conventionally, P is often used to indicate the proportion of a population and p to indicate the proportion of a sample.