Week 4 Lecture Measuring Variability

Question 1

standard deviation (SD)

Answer 1

The standard (or typical) amount that scores deviate from the mean

Question 2

measures of variability

Answer 2

describe how scores in a given dataset differ from one another (e.g., the spread or clustering of points)

Question 3

3 main measures of variability

Answer 3

1. Range
2. Standard Deviation
3. Variance

Question 4

range

Answer 4

• the simplest measure of variability (or disperson)
• It is defined as the difference between highest and lowest scores in a distribution

Question 5

variance

Answer 5

• The averaged squared deviation from the mean (i.e., the square of standard deviation; SD²)
• Mostly a byproduct along the way for getting to standard deviation (which happens to be the square root of variance!)