Chapter 3

Question 1

Bimodal distribution

Answer 1

A distribution with two modes

Question 2

correlations

Answer 2

The relationship between two variables

Question 3

correlation coefficient

Answer 3

A numerical value that expresses he degree of relationship between two variables

Question 4

Descriptive statistics

Answer 4

statistics that describe and summarize data in a meaningful fashion

Question 5

frequency distribution

Answer 5

expresses how often a score occurs in a set of data

Question 6

interval scale of measurement

Answer 6

A scale of measurement in which equal differences in scores represent equal differences in amount of the property measured but with an arbitrary zero point

Question 7

Mean

Answer 7

the arithmetical average of the distribution of scores of scores

Question 8

measures of central tendency

Answer 8

the mean, median, and mode of a distribution of scores

Question 9

median

Answer 9

the middle score in a distribution. It is the score that separates the top half oof the test takers from the bottom half

Question 10

mode

Answer 10

the score in the distribution that occurs frequently

Question 11

multimodel distribution

Answer 11

a distribution with three or more modes

Question 12

negative correlation

Answer 12

An inverse relationship: variables are said to be negatively correlated when a high sore son one is accompanied by a low score on the other. and vise versa

Question 13

negative skewed distribution

Answer 13

A distribution in which more f the scores fall above the mean

Question 14

nominal scale of measurement

Answer 14

nominal data are categorical data. involves observations into carious independent categories and then counting the frequency of occurrence within each of the categories

Question 15

normal curve

Answer 15

In this frequency polygon, most of the scores cluster around the mean. The farther above or below the mean a score appears, the less frequently it occurs.

Question 16

normal distribution

Answer 16

Represents the way test scores would fall if a particular test is given to every single student of the same age or grade in the population for whom the test was designed.

Question 17

ordinal scale of measurement

Answer 17

The scale of measurement that involves the rank order system. It is a scale in which scores indicate only relative amounts or rank order.

Question 18

positive correlation

Answer 18

A direct relationship: Variables are said to be positively correlated when a high score on one is accompanied by a high score on the other. Conversely, low scores on one variable are associated with low scores on the other.

Question 19

positively skewed distribution

Answer 19

A distribution in which more of the scores fall below the mean.

Question 20

Range

Answer 20

The difference between the high score and the low score in the distribution (Range 5 High Score 2 Low Score).

Question 21

Ratio scale of measurement

Answer 21

A scale having interval properties except that a score of zero indicates a total absence of the quality being measured. A score of zero means zero.

Question 22

Skewed distribution

Answer 22

A distribution in which the majority of scores falls at either the high end or the low end rather than the middle of a distribution.

Question 23

Standard deviation

Answer 23

The spread of scores around the mean. In statistics, the standard deviation (SD) (represented by the Greek letter sigma, σ) is a measure that is used to quantify the amount of variation or dispersion of a set of data values.

Question 24

variance

Answer 24

A statistical concept that shows the spread of scores within a distribution.

Question 25

zero correlation

Answer 25

A score which shows no relationship between two variables, so that a change in one is not associated with a change in the other.