Chapter 1

Question 1

Continuous Variables

Answer 1

Continuous variables have values that are real numbers.

Question 2

Convenience Sample

Answer 2

A convenience sample is a sample that is conveniently available. It is the most common type of biased sample.

Question 3

Descriptive Statistics

Answer 3

Descriptive statistics are used to describe the characteristics of a collection of scores, without the goal of inferring something about a population parameter.

Question 4

Discrete Variables

Answer 4

Discrete variables have fixed values. Discrete quantitative variables have values that are integers or whole numbers.

Question 5

Inferential Statistics

Answer 5

Inferential statistics is the act of inferring population parameters from sample statistics.

Question 6

Interval Scales

Answer 6

Interval scales have EQUAL UNITS OF MEASUREMENT but no absolute zero point.

Question 7

Measurement Error

Answer 7

Measurement error refers to the fact that each time something is measured a slightly different score will be obtained

Question 8

Nominal Scale

Answer 8

The values of variables measured on a nominal scale are qualitative and discrete and have no natural ordering.

Question 9

Operational Measure

Answer 9

An operational measure is a tool used to measure a psychological construct. Very often, operational measures are derived from questionnaires. Operational measures may also derive from the speed and accuracy with which psychological tasks are completed.

Question 10

Ordinal Scale

Answer 10

The values of variables measured on an ordinal scale are qualitative and discrete and have a natural ordering, but they do not have a unit of measurement.

Question 11

Parameter

Answer 11

A parameter is a numerical characteristic of a population.

Question 12

Population

Answer 12

A population comprises the scores on a variable of interest, obtained from individuals that share some characteristic of interest.

Question 13

Psychological Construct

Answer 13

A psychological construct is a hypothetical attribute (such as intelligence, introversion, or happiness) that is thought to explain some aspect of behavior, but which cannot be measured directly with a physical measuring device.

Question 14

Qualitative Variables

Answer 14

Qualitative variables have values that are qualities or categories. They are also referred to as nominal or categorical variables.

Question 15

Quantitative Variable

Answer 15

Quantitative (scale) variables have values that are numbers. They often reflect how much of some quantity an individual possesses.

Question 16

Ratio Scales

Answer 16

Ratio scales have units of measurement and an absolute zero. The ratio of two values on a ratio scale expresses their RELATIVE DISTANCES from 0.

Question 17

Reliable

Answer 17

A reliable measuring device gives very similar (if not identical) measurements each time it is applied to the same object.

Question 18

Sample

Answer 18

A sample is a subset of a population.

Question 19

Sampling Bias

Answer 19

Sampling bias means that not all members of the population had an equal chance of being selected in the sample. Sampling bias can and should be avoided.

Question 20

Sampling Distribution

Answer 20

A sampling distribution is a probability distribution of all possible values of a sample statistic based on samples of the same size.

Question 21

Sampling Error

Answer 21

Sampling error is the difference between a statistic and the parameter it estimates. Sampling error cannot be avoided; it is an inevitable feature of random sampling.

Question 22

Score

Answer 22

A score is the value that an individual has on a particular variable.

Question 23

Simple Random Sampling

Answer 23

Simple random sampling means that all members of the population had an equal chance of being selected in the sample.

Question 24

Statistic

Answer 24

A statistic is a numerical characteristic of a sample.

Question 25

Valid

Answer 25

A measuring device is valid if it measures what it is supposed to measure.

Question 26

Variables

Answer 26

Variables are physical or abstract attributes or quantities that we wish to measure. A variable can take on specific values.