Any quantity possessing changing or variable magnitude is known as a variable in statistics.
It should be noted that variable quantities are required to be calculated to solve complex equations. Speeds, velocity and acceleration are the most commonly used examples of variables.
It is usually represented by a Greek or English letter in the lower case. These symbolic letters are used in the equations that also contain one or more constants. Consider the example of a velocity variable v, which is defined as the speed divided by time. The equation given below is used to compute velocity of a moving object:
V = s/t
Where s is the speed of the moving object and t is the time.
As we can see from the equation, V is directly dependent on time and speed.
Any change in speed and time will result in a change in velocity. Depending on the behaviour and properties, variables can also be categorised. There are two types of variables:
- Independent variables
- Dependent variables
Dependent variables depend on other variables in an equation whereas independent variable depends only on constants.
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Random variables represent an event or a series of events or probabilities.
Random variables can also be categorised as either continuous random variables or discrete random variables. In statistics, dependent random variables and independent random variables are known as response variables and explanatory variables respectively.
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