Constant
Topic: Economic Data: Census, NSS, Surveys and Statistical Tools · NCERT: Class 11, Ch 8 "Use of Statistical Tools"
Meaning
A constant is a quantity whose value stays the same throughout a calculation or an investigation. A variable is a quantity that takes different values in different situations, such as income, height or marks. Formulas usually mix the two. The constants stay fixed, and the variable values change from one item to the next.
Example
In the step deviation method, the assumed mean A and the common factor c are constants. Every observation is shifted by the same A and divided by the same c. In a pie diagram, the rule 1% = 3.6° is a constant.
Don't confuse with
- Variable: changes from one observation to the next. Farm income is a variable (500, 550, 600 …), while the 5 in a mean of "3000/5" is a fixed count.