central tendency

Question 1

central tendency

Answer 1

a statistical measure that identifies a single score as a representative for an entire distribution

Question 2

mean

Answer 2

sum of scores divided by the number of scores (μ = ΣX / N; X̄ = ΣX / n)

Question 3

X̄

Answer 3

sample mean

Question 4

μ

Answer 4

population mean

Question 5

characteristics of the mean

Answer 5

(1) changing a score or introducing a new score will change the mean; (2) any constant applied to each score will also apply to the mean

Question 6

median

Answer 6

the score that divides the distribution neatly in half

Question 7

mode

Answer 7

the score with the greatest frequency

Question 8

bimodal

Answer 8

a distribution with two modes (two scores with equally greatest frequency)

Question 9

multimodal

Answer 9

a distribution with more than two modes (more than two scores with equally greatest frequency)

Question 10

advantages of the mode

Answer 10

(1) easy to compute; (2) can be used with any scale of measurement (nominal, ordinal, interval, ratio)

Question 11

distributions best described by the median

Answer 11

(1) there are a few extreme scores; (2) some scores have undetermined values; (3) there is an open-ended distribution; (4) the data are measured on an ordinal scale