In: Statistics and Probability
a. Positive correlation:
If two variables are changed in the same direction then it is known as positive correlation that is if increase in value of one variable associate with increase in value of other variable and vice versa.
For Example: 1. Marks in the examination and and IQ of a student.
2. Demand and supply of a commodity.
b. Negative correlation:
If two variables are changed in the opposite direction then it is known as negative correlation that is if increase in value of one variable is associated with decrease in value of of other variable and vice versa.
For example: 1. Price and Demand of a commodity
2. Speed of a vehicle and time to reach the destination
c. No Correlation:
Change change in one variable is not related to change in other variable then it is known as no correlation.
For Example: 1. Height of the student and his marks in the examination.
2. IQ of a student and his family income.