2.4 Measures of Variation

Question 1

Range (know definition)

Answer 1

Difference between the maximum and minimum data entries.

Question 2

Varience

Answer 2

Mean of the squares of deviation

Question 3

Standard deviation

Answer 3

• square root of the variance
• measure of the typical amount an entry deviates from the mean.
• a low standard deviation indicated that the data points tend to be very close to the mean
• a high standard deviation indicates that the data are spread out over a large range of values.