Nonexperimental and Quasi-Experimental Research Strategies Flashcards
What is a quasi-experimental strategy?
A research strategy that attempts to minimize internal validity and find cause-and-effect, but does not use manipulation or control to make it experimental
What is a nonexperimental research strategy?
A research study that attempts to demonstrate a relationship between two variables by comparison but does not attempt to minimize internal validity nor explains the relationship
What does the term ‘significant’ mean?
It is very unlikely that the difference between the groups of scores would occur if there is no corresponding difference in the population
What are the 2 general categories of non-experimental and quasi-experimental designs?
- Between-subjects
- Within-subjects
What is the purpose of between-subjects designs?
To compare pre-existing groups of individuals
What is the purpose of within-subjects designs?
To compare two or more scores for one group of participants
What is a nonequivalent group design?
A research study where different groups of participants formed under circumstances that do not allow the researcher to randomly assign them
What built-in threat to internal validity do nonequivalent group designs have?
Individual differences
What is a differential research design?
A nonexperimental research design that compares pre-existing groups to establish differences between them
What are differential effects?
Time-related threats to internal validity that impact the groups differently
What is a posttest-only nonequivalent control group design?
A nonexperimental design which two groups are measured at the same time with only one group receiving treatment
What is a nonequivalent control group design?
A research design where the researcher does not randomly assign individuals to groups but uses pre-existing ones - one treatment and one control
What is a pretest-posttest nonequivalent control group design?
A quasi-experimental design comparing two nonequivalent groups where both experimental and groups are measured before and after treatment
What are pre-post designs?
Quasi-experimental and nonexperimental designs consisting of a series of observations made over time for a group of participants
What type of design measures each participant in a group once before and after treatment?
Pretest-posttest design
What is a time-series design?
A series of observations for each participant before and after the treatment or event
A time-series design where an intervening effect occurs that is not manipulated by the researcher is called what?
An interrupted time-series design
What are developmental research designs used for?
Examining changes in behaviour related to age
What between-subjects developmental research design compares different groups, both representing different ages?
Cross-sectional developmental research design
Individuals who are born at roughly the same time and grew up in similar circumstances are called what?
Cohorts
What are generation effects?
Differences between age groups caused by characteristics or experiences other than age
What research design examines development by observing or measuring a group of cohorts over time?
Longitudinal developmental research design
When participants drop out of a study, what is this known as?
Participant mortality/attrition
What is a quasi-independent variable?
The variable that differentiates the groups or conditions being compared in quasi-experimental or nonexperimental designs
