Statistics

Question 1

Average or mean

Answer 1

For a set of n numbers: total sum / n. Affected by unusually high/low values relative to rest of data.

Question 2

Median

Answer 2

Middlemost value when numbers are arranged in ascending order; for an even amount of numbers, take the average of the middle two. Fairly unaffected by unusually high/low values relative to rest of data.

Question 3

Mode

Answer 3

The number that occurs most frequently

Question 4

Weighted average

Answer 4

(proportion) x (group A average) + (proportion) x (group B average) + …

Question 5

Range

Answer 5

Greatest value – least value, directly affected by outliers

Question 6

Standard deviation

Answer 6

Represents the average distance the data values are away from the mean. To find 1) calculate mean (m) of n values 2) find difference btwn m and each n value 3) square each difference 4) find avg of the n squared differences 5) take nonnegative sqrt of avg squared differences