Ch 3 - Research Methods and Designs

Question 1

What are the steps to good experimental design?

Answer 1

Select population (scope), operationalize independent and dependent variables, select control and experimental groups, randomly sample population, randomly assign individuals to groups, measure results, test hypothesis

Question 2

What is the independent variable?

Answer 2

Variable that is directly manipulated by the researchers

Question 3

What is the dependent variable?

Answer 3

Variable that is measured - quantitative

Question 4

What is reproducibility?

Answer 4

A quality of research design that allows other researchers or whoever to conduct the same experiment and come to the same result

Question 5

What is an operational definition?

Answer 5

A strict specification of what each variable means in the context of the experiment

Question 6

What are the experimental and control groups?

Answer 6

Experimental - group that receives treatment

Control - doesn’t receive treatment, reference group

Question 7

What are homogenous control groups?

Answer 7

Groups that are similar throughout

Question 8

Why must control groups be homogenous and be as similar as possible to the experimental group?

Answer 8

To rule out extraneous (confounding) variables that are related to differences between individuals within the group and between the two groups

Question 9

Why must studies be double-blind?

Answer 9

To reduce and avoid the placebo effect

Question 10

What is sampling bias?

Answer 10

A type of selection bias. Sampling bias is a bias in which a sample is collected in such a way that it results in a biased sample of a population in which all individuals, were not equally likely to have been selected. Threatens external validity, or generalization of the study.

Question 11

What is selection bias?

Answer 11

General category of system flaws in a design that can compromise results, such as which studies to evaluate in a meta analysis. Threaten internal validity.

Question 12

What is attrition?

Answer 12

Participants dropping out of the study. If non-random, can introduce a confounding variable

Question 13

What is randomized block technique?

Answer 13

With a randomized block design, the experimenter divides subjects into subgroups called blocks, such that the variability within blocks is less than the variability between blocks. Then, subjects within each block are randomly assigned to treatment conditions.

Question 14

What are the two components of instrument reliability?

Answer 14

Construct validity and replicability

Question 15

What is psychometrics?

Answer 15

Study of how to measure psychological variables through testing

Question 16

What is response bias?

Answer 16

Tendency for respondents to not have perfect insights into their state and provide inaccurate responses

Question 17

What are between-groups studies?

Answer 17

Studies that compare different groups (experimental vs control)

Question 18

What are within-group studies?

Answer 18

Studies that compare within the same group at different time points (before and after treatment/study)

Question 19

What are mixed methods studies?

Answer 19

Any combination of different study approaches (between-groups and within-groups, quantitative and qualitative)

Question 20

What is type-2 error?

Answer 20

False negative

Question 21

What is type-1 error?

Answer 21

False positive

Question 22

What is a null hypothesis?

Answer 22

A hypothesis that assumes no causal relationship between the variables and any effect that they measure

Question 23

What is a significant difference?

Answer 23

Measured difference between two groups of an experiment that is large enough that it is probably not due to chance

Question 24

What is a p-value?

Answer 24

Number between 0 and 1 that represents the threshold for a significant difference in the experiment

Question 25

What is sample size?

Answer 25

Number of participants

Question 26

What is the power of an experiment?

Answer 26

Ability to pick up an effect if one is actually present

Question 27

What is external validity?

Answer 27

Ability to apply conclusions of a study to the real world

Question 28

What is internal validity?

Answer 28

How well the experiment was set up to reduce doubts in regards to inherent flaws

Question 29

What is demand characteristics?

Answer 29

Participants interpret what the experiment is about and subconsciously respond in ways that are consistent with the hypothesis

Question 30

What is a disclosure used for?

Answer 30

To clarify incentives and expectations while reminding participants of their right to terminate the experiment at any time.

Question 31

What kinds of non-experimental study designs are there?

Answer 31

Correlational, ethnographic, twin studies, longitudinal, case studies, phenomenological, surveys, archival studies, biographical studies, observational studies

Question 32

What is a Pearson correlation?

Answer 32

Correlation described quantitatively between -1 and +1. Negative = inverse linear relationship, positive = linear relationship, zero = no linear relationship (non-linear relationship possible)

Question 33

What is the difference between longitudinal and cross-sectional studies?

Answer 33

Longitudinal - data points of a single sample throughout their life
Cross-sectional - data points of fresh samples either once or throughout time

Question 34

What is the difference between case study and a phenomenological study of one?

Answer 34

Case study - detailed exploration of one individual or case - from the researchers perspective
Phenomenological - detailed exploration interested in describing phenomena - from the subjects point of view