Measures of Variability

Question 1

Range of distribution

Answer 1

highest minus lowest score

Question 1

interquartile range

Answer 1

range of the middle 50% of the observations
75th minus 25th percentile
midpoint 2 minus midpoint 1

Question 2

the variance

Answer 2

the most accurate measure of variability

Question 3

sample variance

Answer 3

you will do N-1 because its sample and the symbol is “s”

Question 4

population variance

Answer 4

symbol looks like “o”
you don’t need to subtract a 1 on bottom because it’s a population

Question 5

standard deviation

Answer 5

the positive square root of the variance