Variance is a measure of how far numbers are spread from their average value and is equal to the square of the standard deviation. There are two types of variance: population variance, which measures the spread of an entire group, and sample variance, which measures a subset of the population. Population variance is calculated using the population mean, while sample variance uses the sample mean. The document provides formulas and explanations for calculating variance in different contexts.

1. TOPIC-VARIANCE STUDY

2. VARIANCE
CALCULATION IN EXCEL  WHAT ISVARIANCE-
• Variance is the expected value of the squared
variation of a random variable from its mean
value, in probability and statistics. Informally,
variance estimates how far a set of numbers
(random) are spread out from their mean
value.
• The value of variance is equal to the square of
standard deviation.
• Represented by- σ2 , S2 or var(x)
 KEY POINT- Standard deviation
 What is the relation between variance and
standard deviation?

3. TYPESOFVARIANCE
VARIANCE
POPULATION
VARIANCE
SAMPLE VARIANCE

4.  Specific group
 Size is small
 Subset of population
 Entire group
 Size is large
 Complete set

5. FORMULAOFTWOTYPESOFVARIANCE
POPULATION VARIANCE SAMPLE VARIANCE
σ2 – population variance
X - individual number
µ - population mean
N – number of observation
S2 - sample variance
X - individual number
x̄ - sample mean
N – number of observation

6. POPULATIONVARIANCE

7. CALCULATIONOFSAMPLEVARIANCE

8. THANKYOU