PSYCH 100 - Chapter 2 part 2

Question 1

control (or comparison) group

Answer 1

In an experiment, a group or condition in which some proposed cause is not present. (2.9)

Question 2

placebo condition

Answer 2

In an experiment, a group or condition in which people expect to receive a treatment but are exposed only to an inert version, such as a sugar pill. (2.9)

Question 3

random sampling

Answer 3

A way of choosing a sample of participants for a study in which participants are selected without bias, for example, by dialing random digits on the telephone or pulling names out of a hat. (2.1)

Question 4

validity

Answer 4

The appropriateness or accuracy of a conclusion or decision. (2.13)

Question 5

construct validity

Answer 5

The specific assessment of how accurately the operationalizations used in a study capture the variables of interest. (2.13)

Question 6

reliability

Answer 6

The degree to which a measure yields consistent results each time it is administered. (2.13)

Question 7

external validity

Answer 7

The degree to which it is reasonable to generalize from a study’s sample to its population of interest. (2.14)

Question 8

internal validity

Answer 8

The ability of a study to rule out alternative explanations for a relationship between two variables; one of the criteria for supporting a causal claim. (2.15)

Question 9

confound

Answer 9

An alternative explanation for a relationship between two variables; specifically, in an experiment, when two experimental groups accidentally differ on more than just the independent variable, which causes a problem for internal validity. (2.15)

Question 10

descriptive statistics

Answer 10

A graph or computation that describes the characteristics of a batch of scores, such as its distribution, central tendency, or variability. (2.17)

Question 11

frequency distribution

Answer 11

A descriptive statistic that takes the form of a bar graph in which the possible scores on a variable are listed on the x-axis and the total number of people who had each score is plotted on the y-axis. (2.17)

Question 12

mean

Answer 12

A measure of central tendency that is the arithmetic average of a group of scores. (2.17)

Question 13

median

Answer 13

A measure of central tendency that is the middlemost score; it is obtained by lining up the scores from smallest to largest and identifying the middle score. (2.17)

Question 14

mode

Answer 14

A measure of central tendency that is the most common score in a batch of scores. (2.17)

Question 15

variability

Answer 15

The extent to which the scores in a batch differ from each other. (2.17)

Question 16

standard deviation

Answer 16

A variability statistic that calculates how much, on average, a batch of scores varies around its mean. (2.17)

Question 17

effect size

Answer 17

A numerical estimate of the strength of the relationship between two variables. It can take the form of a correlation coefficient or, for an experiment, the difference between two group means divided by the standard deviations of the two groups. (2.18)

Question 18

inferential statistics

Answer 18

A set of procedures used to estimate whether a pattern of results represents a true relationship or difference in the population. (2.19)

Question 19

statistical significance

Answer 19

A process of inference that applies rules of logic and probability to estimate whether the results obtained in a study’s sample are the same in a larger population. (2.19)

Question 20

meta-analysis

Answer 20

A process in which researchers locate all of the studies that have tested the same variables and mathematically average them to estimate the effect size of the entire body of studies. (2.19)

Question 21

Institutional Review Board, IRB

Answer 21

A local panel of researchers, teachers, citizens, and others who determine whether a research study lives up to the community’s ethical standards. (2.20)

Question 22

informed consent

Answer 22

An application of the ethical principle of autonomy, in which a researcher explains the procedures of a study, including its risks and potential benefits, to the potential participants, who then decide whether to take part. (2.20)

Question 23

false positive

Answer 23

A statistically significant finding that does not reflect a real effect. (2.22)

Question 24

HARKing (hypothesizing after the results are known)

Answer 24

A questionable research practice in which researchers create an after-the-fact hypothesis about an unexpected research result, making it appear as if they predicted it all along. (2.22)

Question 25

p-hacking

Answer 25

A family of questionable data analysis techniques, such as adding participants after the results are initially analyzed, looking for outliers, or trying new analyses in order to obtain a p value of just under .05, which can lead to nonreplicable results. (2.22)

Question 26

open science

Answer 26

The practice of sharing one’s data, hypotheses, and materials freely so others can collaborate, use, and verify the results. (2.22)

Question 27

preregistration

Answer 27

A researcher’s public statement of a study’s expected outcome before collecting any data. (2.22)