Interpret Standard deviation and mean
CONCEPTS
Statistics
• Describes the characteristics of a set or population of numbers
• There are many metrics used in statistics, including mean, median, & mode. Advanced metrics include standard deviation (meaning spread or variation) or range (max – min)
Histogram / PDF / Frequency Plot
• A histogram (or probability density function) shows the mean and the standard deviation for a given set of data.
• Mean defines the average of the data (see mean below)
• Standard deviation (σ) defines the spread of the data (see -3 sd, -2 sd, etc below)
• A normal distribution shows the typical distribution of data for a survey
PRACTICE PROBLEMS
Question 1 A group of students from high school A has an average grade of 89 and a group of students from high school B has an average score of 95. Both grade-sets have the same distribution shape. What statistical factor is different between the group of students...mean, standard deviation, or range?
-- Answer -- mean
The standard deviation and range are the same because the distribution of grade between the groups of students is the same.
ACT PRACTICE PROBLEMS
