Research Design Flashcards
What is the best way to control threat to internal validity?
random ASSIGNMENT
What is the difference between random assignment and random sampling?
random assignment = method of assignment to a group
random sampling = method of selection into the study
Controls for threats to internal validity
random assignment (BEST) matching blocking holding extraneous variable constant ANCOVA
Studying subject characteristics as if it were another IV is called ______.
blocking
grouping similar subjects, THEN randomly assigning to treatment groups is called __________.
matching
What are the threats to external validity?
Interactions between:
selectiontreatment
testing treatment
history treatment
demand characteristics
order effects in repeated measures studies
When a researcher collects data on two variables for the same group of subjects and measures the degree of relationship between the variables, it is called __________.
correlational design
In this research design, the DV is measured several times, at regular intervals, both before and after treatment is administered.
time-series design
What is the research design called when groups of subjects are divided by age and assessed at the same time?
cross-sectional
What is the research design called that combines longitudinal and cross-sectional designs?
cross-sequential
representative groups are assessed on several occasions
What is the research design called when multiple measurements are taken over time?
time series
Threats to internal validity
history maturation testing effects instrumentation (change in nature of instrument) selection statistical regression differential mortality (systemic difference between groups, such as some drop out of study) experimenter bias
