Question

What is a numerical variable and what is a categorical variable?

Answer 1

Hint: The above these topics are the part of statistics. Statistics is the branch of mathematics. Statistics provides the exact description and better understanding. It helps in designing the effective and proper planning of the statistical inquiry in any field. It gives valid inference with the reliability measures about the population parameters from the sample data.

Complete step by step solution:
Here we will discuss the topics of statistics which are numerical variable and categorical variable.
Numerical variable is a variable where the measurement or number has a numerical meaning. Numerical variable is also known as a continuous variable. Numerical variables give a number such as age. Discrete variables are numerical variables that come from a limited set of numbers. Sometimes they may result from answering questions such as `how many` etc. continuous variables are numerical variables that can take any value such as weight.
There are two types of numerical variables.
1. Interval variables
2. Ratio variables
The some examples of numerical variable are:
Total rainfall measured in inches is a numerical value, heart rate is a numerical value, number of cheeseburgers consumed in an hour is a numerical value.
Categorical variable is a category or type. Categorical data is a collection of information that is divided into groups. It has no intrinsic ordering to the categories. Sometimes they are recorded as numbers but the numbers represent categories rather than actual amounts of things. Categorical variables can be expressed as a number for the purpose of statistics, but these numbers do not have the same meaning as a numerical value.
There are three types of categorical variables:
1. Binary variable
2. Nominal variable
3. Ordinal variable
Let's take an example of categorical variables. If I am studying the effects of three different medications on an illness, I may name the three different medicines, medicine 1, medicine 2, medicine 3. However, medicine three is not greater, or stronger, or faster than medicine one. These numbers are not meaningful.

Note: The uses of categorical variables that are used in height, weight, age, number of movies watched, IQ etc. to graph numerical data one uses dot plots, stem and leaf graph, histograms, box plots, scatter plots. A categorical value can take values like identification number, postal code, phone number, etc. the only difference in both these variables is that arithmetic operations cannot be performed on the values taken by categorical data.