Chapter 1

Question 1

How do you make frequency distributions when there are lots of possible values or many decimal places?

Answer 1

find intervals

Question 2

2 branches of statistics

Answer 2

descriptive and inferential

Question 3

Descriptive statistics

Answer 3

used to organize, summarize, communicate a group of numerical observations in just one number

Question 4

Inferential statistics

Answer 4

uses sample data to make estimates about the population

Question 5

Population

Answer 5

all possible observations about which we are interested in

Question 6

Variables

Answer 6

observations of physical, attitudinal, and behavioral characteristics that can take on different values

Question 7

Discrete observations

Answer 7

can only take on specific whole numbers with no values in between numbers e.g. nominal and ordinal

Question 8

Continuous observations

Answer 8

can take on a full range of values and an infinite number of potential values exists e.g. interval and ratio (can be discrete too)

Question 9

Nominal variables

Answer 9

observations with categories or names as their values

Question 10

Ordinal variables

Answer 10

observations that have rankings as their values

Question 11

Interval variables

Answer 11

observations wherein the distance between their numbers/values is equal

Question 12

Ratio variables

Answer 12

meet the criteria for interval variables but also have meaningful zero points

Question 13

Scale variable

Answer 13

meets criteria for an interval variable or a ratio variable

Question 14

Levels

Answer 14

discrete values or conditions that variables can take on

Question 15

3 types of variables considered in research

Answer 15

independent, dependent, confounding

Question 16

Confounding variable

Answer 16

any variable that systematically varies with the IV so that we can’t logically determine which variable is at work

Question 17

Reliability vs. validity

Answer 17

consistency of a measure vs. extent to which a test measures what it was intended to measure

Question 18

Hypothesis testing

Answer 18

process of drawing conclusions about whether a particular relation between variables is supported by the evidence

Question 19

Operational definition

Answer 19

procedures used to measure or manipulate a variable

Question 20

Random assignment

Answer 20

every participant has an equal chance of being assigned to an experimental condition or group; diminishes the effect of potential confounds

Question 21

Experiment

Answer 21

a study in which participants are randomly assigned to a condition or level of 1 or more IVs

Question 22

Between-groups research design

Answer 22

participants experience only one level of the IV, divided into control group and experimental group

Question 23

Within-groups research design/Repeated measures

Answer 23

participants experience all the different levels of the IV

Question 24

Data ethics

Answer 24

a set of principles related to all stages of working with data (research design, data collection, statistical analyses, interpretation, reporting outcomes)

Question 25

Open science

Answer 25

an approach to research that encourages collaboration, includes sharing of methodology, data, and statistical analyses to enable inquiries and duplication

Question 26

Sources of the current crisis in psychological science

Answer 26

replication failures, problems with data collection, old-fashioned statistics

Question 27

Severe testing

Answer 27

subjecting a hypothesis to rigorous statistical scrutiny aimed at uncovering any of its flaws

Question 28

Preregistration

Answer 28

a recommended open-science practice where researchers outline their research design and analysis plan before conducting a study

Question 29

HARKing

Answer 29

Hypothesizing after the results are known; an unethical practice where researchers change their hypotheses to match their findings