## Variability

• Variability describes how far apart data points lie from each other & from center of the distribution
• Variability is also referred as spread, scatter or dispersion & is most commonly measured with the following
• Variance: Variance measures the dispersion of set of data points around the mean
• Standard deviation: average distance from mean
• We would have different formulas for
• Population Data
• Sample Data
• Variance:
• Population Variance:
• Formula: • Sample Variance:
• Formula: • Lets calculate variance for a sample data Refer Here  • Standard Deviation
• Sample Standard Deviation formula • Population Standard Deviation formula  • You have the annual personal income from 11 people from Hyderabad. Decide whether you need to use sample or population formula for variance.
• Calculate the variance and standard deviation
• Refer Here for the excel  • Coeffecient of variation:
• This is referred as relative standard deviation
• Formula: `standard deviation/mean`
• Refer Here this excel sheet and calculate standard deviation for new york and hyderabad pizza prices • Exercise: Calculate standard deviation and coefficient of variation for the following excel Refer Here

This site uses Akismet to reduce spam. Learn how your comment data is processed. 