Chapter 4

Question 1

measures of central tendency

Answer 1

scores that represent the center of the distribution

Question 2

mean

Answer 2

any set of raw scores is the sum of all of the scores divided by the total number of scores

Question 3

median

Answer 3

middle score, with half the scores above and half the scores below, when all the scores have been ranked, or placed in numerical order

Question 4

quartiles

Answer 4

divide the distribution into quarters

Question 5

first quartile

Answer 5

one-quarter of the way through the distribution

Question 6

second quartile

Answer 6

halfway through the distribution

Question 7

third quartile

Answer 7

three-quarters of the way through the distribution

Question 8

mode

Answer 8

the most frequent score

Question 9

skew

Answer 9

refers to the general shape of a distribution when it is graphed as a frequency polygon

Question 10

measures of variability

Answer 10

give an idea of how much scores in the distribution vary from that one average score

Question 11

range

Answer 11

measure of the full extent of the scores in a distribution, from the highest to lowest

Question 12

average mean distribution

Answer 12

average deviation of each score from the mean of teh distribution

Question 13

deviation scores

Answer 13

mean deviations (“little x’s”)

Question 14

variance

Answer 14

population is the actual computed variance of the population, whereas the sample variance is an estimate of the population variance using only the values in the sample

Question 15

standard deviation

Answer 15

sqaure root of the variance (s)

Question 16

scaled scores

Answer 16

scores that are adjusted via some type of scale (addition, subtraction, multiplication, or division)

Question 17

standard score

Answer 17

z score

Question 18

standard score

Answer 18

scaled scores that have the same mean and standard deviation

Question 19

z score distribution

Answer 19

has a mean of 0 and a standard deviation of 1