Categorical & Numerical Variables

Variables are the basic building blocks of an ML algorithm. Based on these variables, the algorithm identifies and equation which will be applied on new input data. These variables are mostly of two types:

  1. Categorical Variables
    This variable represents a field which can be classified into categories or groups.
    example : sex, favorite color, age
  2. Numerical Variables
    This variable represents a field which can be measured and sorted.
    example : height, weight

Categorical variables are visualized using bar charts, frequency tables or pie charts.

http://www.saedsayad.com/categorical_variables.htm

visualizing categorical data

Numerical variables are visualized using scatter plots or line graphs.

http://www.saedsayad.com/numerical_numerical.htm

visualizing numerical data

An interesting reference : Shodor – Numerical and Catagorical data

In my next blog, I will be writing on Supervised Learning.