Chapter 2: Methods in Psychology

Question 1

empiricism

Answer 1

belief that accurate knowledge can be acquired through observation

Question 2

scientific method

Answer 2

set of principles about the appropriate relationship between ideas and evidence

Question 3

theory

Answer 3

a hypothetical explanation of a natural phenomenon

Question 4

hypothesis

Answer 4

a falsifiable prediction made by a theory

Question 5

empirical method

Answer 5

a set of rules and techniques for observation

Question 6

operational definition

Answer 6

a description of a property in concrete measurable terms

Question 7

measure

Answer 7

a device that can detect the condition to which an operational definition refers

Question 8

electromyograph (EMG)

Answer 8

a device that measures muscle contractions under the surface of a person’s skin

Question 9

validity

Answer 9

the extent to which a measurement and a property are conceptually related

Question 10

reliability

Answer 10

the tendency for a measure to produce the same measure for the same thing

Question 11

power

Answer 11

the ability of a measure to detect the concrete conditions specified in the operational definition

Question 12

demand characteristics

Answer 12

those aspects of an observational setting that cause people to behave as they think they should

Question 13

naturalistic observation

Answer 13

a technique for gathering scientific scientific information by unobtrusively observing people in their natural environments

Question 14

double-blind

Answer 14

an observation whose true purpose is hidden from both the observer and the person being observed

Question 15

frequency distribution

Answer 15

a graphical representation of measurements arranged by the number of times each measurement was made

Question 16

normal distribution

Answer 16

a mathematically defined frequency distribution in which most measurements are concentrated around the middle

Question 17

mode

Answer 17

the value of the most frequently observed measurement

Question 18

mean

Answer 18

the average value of all the measurements

Question 19

median

Answer 19

the value that is in the middle of all measurements

Question 20

range

Answer 20

the value of the largest measurement in a frequency distribution minus the value of the smallest measurement

Question 21

standard deviation

Answer 21

a statistic that describes the average difference between the measurements in a frequency distribution and the mean of that distribution

Question 22

variable

Answer 22

a property whose value can vary across individuals or over time

Question 23

correlation

Answer 23

when variables in the value of one variable are synchronized with variations in the value of the other

Question 24

correlation coefficient

Answer 24

a measure of the direction and strength of a correlation which is signified by the letter r

Question 25

natural correlation

Answer 25

a correlation observed in the world around us

Question 26

third-variable correlation

Answer 26

the fact that two variables are correlated only because each is causally related to a third variable

Question 27

matched samples

Answer 27

a technique whereby the participants in two groups are identical in terms of a third variable

Question 28

matched pairs

Answer 28

a technique whereby each participant is identical to one other participant in terms of a third variable

Question 29

third-variable problem

Answer 29

the fact that a causal relationship between two variables cannot be inferred from the naturally occurring correlation between them because of the ever-present possibility of third-variable correlation

Question 30

experiment

Answer 30

a technique for establishing the causal relationship between variables

Question 31

manipulation

Answer 31

creation of an artificial pattern of variation in a variable in order to determine its causal powers

Question 32

independent variable

Answer 32

the variable that is manipulated in an experiment

Question 33

experimental group

Answer 33

the group of people who are treated in a particular way as compared to the control group in an experiment

Question 34

control group

Answer 34

the group of people who are not treated in the particular way that the experimental group is treated in an experiment

Question 35

dependent variable

Answer 35

the variable that is measured in a study

Question 36

self-selection

Answer 36

a problem that occurs when anything about a person determines whether he or she will be included in the experimental or control group

Question 37

random assignment

Answer 37

procedure that uses a random event to assign people to the experimental or control group

Question 38

internal validity

Answer 38

the characteristic of an experiment that establishes the causal relationship between variables

Question 39

external validity

Answer 39

a property of an experiment in which the variables have been operationally defined in a normal, typical, or realistic way

Question 40

population

Answer 40

complete collection of participants who might possibly be measured

Question 41

sample

Answer 41

the partial collection of people drawn from a population

Question 42

case method

Answer 42

method of gathering scientific knowledge by studying a single individual

Question 43

random sampling

Answer 43

technique for choosing participants that ensures that every member of a population has an equal chance of being included in the sample

Question 44

informed consent

Answer 44

a written agreement to participate in a study made by an adult who has been informed of all the risks that participation may entail

Question 45

debriefing

Answer 45

a verbal description of the true nature and purpose of a study