Ch. 10: The Nonexperimental and Quasi-Experimental Strategies

Question 1

similarity between the nonexperimental and quasi-experimental research strategies

Answer 1

involve comparisons of scores from different groups or different conditions

Question 2

differences between the nonexperimental and quasi-experimental designs

Answer 2

• The nonexperimental design makes little or no attempt to minimize threats to internal validity
• The quasi-experimental design makes some attempt to minimize threats to internal validity and approaches the rigour of a true experiment

Question 3

key elements of nonexperimental and quasi-experimental designs

Answer 3

• Often look like experiments in terms of their general structure
• Produces groups of scores to be compared for significant differences
• One variable is used to create the groups or conditions to be compared and the second is measured to obtain a set of scores within each condition
• Groups are defined in terms of a specific participant variable or in terms of time

Question 4

two general categories of nonexperimental and quasi-experimental designs

Answer 4

• between-subjects (nonequivalent group designs)
• within-subjects (pre-post designs)

Question 5

nonequivalent group design

Answer 5

a research study in which the different groups of participants are formed under circumstances that do not permit the researcher to control the assignment of individuals to groups, and the groups of participants are therefore, considered nonequivalent

Question 6

is random assignment used in nonequivalent designs?

Answer 6

no, the researcher cannot use random assignment to create groups of participants

Question 7

what is the main threat to internal validity in nonequivalent group designs

Answer 7

individual differences

Question 8

Three common examples of nonequivalent group designs

Answer 8

• The differential research design
• The posttest-only nonequivalent control group design
• The pretest-posttest nonequivalent control group design

Question 9

differential research design

Answer 9

a research study that compares preexisting groups

Question 10

what type of research design is differential research?

Answer 10

nonexperimental nonequivalent group design

Question 11

how do researchers assign participants to groups in the differential research design?

Answer 11

using participant characteristics

Question 12

measurement of the dependent variable in the differential research design

Answer 12

A DV is then measured for each participant to obtain a set of scores within each group

Question 13

goal of the differential research design

Answer 13

to determine whether the scores of one pre-existing group are consistently different from the scores of another pre-existing group

Question 14

synonym for the differential research design

Answer 14

ex post facto research because it looks at differences after the fact

Question 15

similarities between differential and correlational research

Answer 15

• A researcher simply observes two naturally occurring variables without any manipulation
• The results are interpreted in the same way
• Neither allows for a cause-and-effect explanation of a relationship

Question 16

differences between differential and correlational research

Answer 16

• In differential research, the participant differences in one variable are used to create separate groups and the measurements of the second variable are made within each group. The researcher then compares the measurements for one group with the measurements from another
• In correlational research, the researcher treats all participants as a single group and simply measures the two variables for each individual
• They use different statistical analyses

Question 17

nonequivalent control group design

Answer 17

uses preexisting groups, one of which serves in the treatment condition and the other in the control condition. The researcher does not randomly assign individuals to the groups

Question 18

what type of research design is the nonequivalent control group design?

Answer 18

nonexperimental nonequivalent group design

Question 19

posttest-only nonequivalent control group design

Answer 19

compares two nonequivalent groups of participants. One group is observed (measured) after receiving treatment, and the other group is measured at the same time but receives no treatment

Question 20

what type of research design is the posttest-only nonequivalent control group design

Answer 20

nonexperimental nonequivalent group design

Question 21

synonym for a posttest-only nonequivalent control group design

Answer 21

static group comparison

Question 22

posttest-only nonequivalent control group design annotation

Answer 22

• Annotated using X and O, where X corresponds to the treatment and O corresponds to the observation or measurement
• A R is placed as the first symbol in each line of notation if the study used random assignment

Question 23

what type of research design is the pretest-posttest nonequivalent control group design?

Answer 23

a quasi-experimental nonequivalent group design

Question 24

pretest-posttest nonequivalent control group design

Answer 24

compares two non-equivalent groups. One group is measured twice, once before a treatment is administered, and once after. The other group is measured at the same two times but does not receive any treatment

Question 25

annotation of pretest-posttest nonequivalent control group design

Answer 25

O X O (treatment group) O O (nonequivalent control group)

Question 26

benefits of the pretest-posttest nonequivalent control group design

Answer 26

- Allows researchers to determine whether the treatment or some other, time-related factor is responsible for the changes - The addition of a pretest reduces threats to internal validity associated with individual differences - Can provide some evidence to support a cause-and-effect relationship

Question 27

what variables can become confounding in pretest-posttest nonequivalent control group designs?

Answer 27

time-related variables because groups are nonequivalent and often in separate locations

Question 28

history effects

Answer 28

the influence of outside events

Question 29

differential effects

Answer 29

when history effects differ from one group to another

Question 30

pre-post designs

Answer 30

a research study in which a series of observations is made over time for one group of participants

Question 31

goal of pre-post designs

Answer 31

to evaluate the influence of the intervening treatment or event by comparing the observations made before treatment with the observations made after treatment

Question 32

what type of design are pre-post designs similar to?

Answer 32

the pretest-posttest nonequivalent control group design

Question 33

differences between the pretest-posttest nonequivalent control group design and the pre-post designs

Answer 33

- pre-post designs have no control group - the primary focus of its control group is to compare the treatment scores to the control group, not to compare the pretest scores with the posttest scores

Question 34

threats to internal validity for pre-post designs

Answer 34

time-related factors

Question 35

5 categories of time-related threats

Answer 35

- History - Instrumentation - Order effects - Maturation - Statistical regression

Question 36

pre-post designs vs. within-subjects experimental designs

Answer 36

- Pre-post designs are similar to the within-subjects experimental design - However, the within-subjects design uses counterbalancing to control time-related variables - In a pre-post design, it is impossible to counterbalance the order of treatments

Question 37

pretest-posttest design

Answer 37

each individual in a single group of participants is measured once before treatment and once after treatment

Question 38

what type of research design is the pretest-posttest design?

Answer 38

a nonexperimental pre-post design

Question 39

annotation of the pretest-posttest design

Answer 39

O X O

Question 40

time-series design

Answer 40

has a series of observations for each participant before a treatment or event and a series of observations after the treatment or event

Question 41

treatment

Answer 41

a manipulation administered by the researcher

Question 42

event

Answer 42

an outside occurrence that is not controlled or manipulated by the researcher

Question 43

what type of research design is the time-series design?

Answer 43

a quasi-experimental pre-post design

Question 44

annotation of the time-series design

Answer 44

O O O X O O O

Question 45

is the treatment manipulated by the researcher in a time-series design?

Answer 45

The intervening treatment/event (x) may or may not be manipulated by the researcher

Question 46

interrupted time-series design

Answer 46

a study in which the intervening event is not manipulated by the researcher

Question 47

applications of the time-series design

Answer 47

- Can be used to investigate the effect of a predictable event - This design can be applied to single individuals or organizations

Question 48

why is the time-series design considered quasi-experimental?

Answer 48

The series of observations allows a researcher to see any trends that may already exist and minimize most threats to internal validity

Question 49

when are external events threats to internal validity in the time-series design?

Answer 49

only if it occurs simultaneously with the treatment

Question 50

developmental research design

Answer 50

used to examine changes in behaviour related to age

Question 51

two basic types of developmental research designs

Answer 51

- Cross-sectional design - Longitudinal design

Question 52

cross-sectional developmental research design

Answer 52

uses different groups of individuals, each group representing a different age. The different groups are measured at one point in time and then compared

Question 53

what type of research design is the cross-sectional developmental design?

Answer 53

a nonexperimental nonequivalent design

Question 54

strengths of the cross-sectional design

Answer 54

- Data can be collected in a short period - Doesn’t require long-term cooperation between the researcher and the participants

Question 55

limitations of the cross-sectional design

Answer 55

- The researcher can’t say anything about how a particular individual develops over time - Factors other than age may differentiate the groups (cohort and generation effects)

Question 56

cohorts

Answer 56

individuals who were born at roughly the same time and grew up under similar circumstances

Question 57

cohort/generational effects

Answer 57

the differences between cohorts caused by unique experiences other than age

Question 58

when are cohort effects more likely?

Answer 58

when there are large age differences between the groups

Question 59

longitudinal developmental research design

Answer 59

examines development by observing or measuring a group of cohorts over time

Question 60

what type of research design is the longitudinal developmental design?

Answer 60

a nonexperimental pre-post design

Question 61

what kind of treatments are administered in the longitudinal developmental research design?

Answer 61

No treatment is administered; the treatment is age

Question 62

strengths of the longitudinal design

Answer 62

- The absence of cohort effects - You can discuss how a single individual changes with age

Question 63

limitations of the longitudinal design

Answer 63

- Time-consuming - Expensive - Subject to high participant attrition, which decreases internal validity - Potential for practice effects

Question 64

participant attrition

Answer 64

when participants drop out of a study before completion

Question 65

cross-sectional longitudinal designs

Answer 65

research studies that compare the results obtained from separate samples (like a cross-sectional design) that were obtained at different times (like a longitudinal design)

Question 66

typical usage of cross-sectional longitudinal designs

Answer 66

This is typically examining the development of phenomena other than individual aging