PBSI 302 Final Exam questions with
verified answers passed
Quasi-Experimental Designs - correct answer ✔✔Aims to establish a cause-and-effect
relationship between an independent and dependent variable. Groups already exist.
Characteristics of a Quasi-Experiment - correct answer ✔✔No random assignment (still assigned
to groups, just not randomly)
Often no control over treatments (groups already exist)
Problems with Quasi-Experiments - correct answer ✔✔Pre-existing differences between groups
creates a lack of equivalence
Manipulated Independent variable and group membership is confounded (because participants
are assigned to conditions based on group members
Quasi-experiment: Single factor design without manipulation - correct answer ✔✔One
Independent variable/membership
levels of the IV are pre-existing
Example: like a political party/contrasting views
Quasi-experiment: Single factor design with manipulation - correct answer ✔✔Two groups of
subjects assigned to two different conditions
,Independent Variable confounds with group membership
Quasi-experiment: Mixed Factorial Design With Manipulation - correct answer ✔✔One
Between-subjects group, Independent variable is not manipulated
One within subjects experimental group where the Independent variable is manipulated.
Mixed factorial design with manipulation example - correct answer ✔✔Breast fed vs Formula
fed babies spend time with dad, how does that influence attachment?
Breast fed vs formula fed - between subjects, not manipulated
Both groups will have 10 or 20 minutes with dad - within subjects, amount of time each group
gets is manipulated.
Quasi Experimental Designs: Nonequivalent-Control Group Design - correct answer ✔✔There is
an experimental and a control group that were naturally existing (no random assignment so
they're not equal) and you just observe the changes over time
Quasi Experimental Designs: Delayed Control Group - correct answer ✔✔Pre and post testing of
the control group does not happen at the same time as the experimental group, this usually
happens when both groups are not accessible at the same time.
Desired Results for Non-equivalent Control Group Design - correct answer ✔✔Pretest starts off
different
Experimental group changes and control does not
,Uninterpretable results for nonequivalent control group design - correct answer ✔✔Control
group is higher or lower at ceiling/floor effect you do not know if it is possible for them to
change during the experiment
Control group could also just naturally change due to maturation or pre-testing effects even if
they don't receive the treatment
Interrupted Time Series Design - correct answer ✔✔Tracks ONE group over time looking at
before and after treatment to see effects as a result of when treatment was introduced
Pretest, pretest, pretest (sets base line), Treatment, post test (tells us if there is actually a
difference compared to our base line)
Multiple Time-Series Design - correct answer ✔✔Both a control and experimental group receive
multiple pre-test, the treatment, and then multiple post tests.
Same as interrupted time series design except there is a control group.
Repeated Treatment Design - correct answer ✔✔Control Group (between subjects)
Pre-test, treatment, post-test; Pre-test2, treatment, Post-test2
Withdrawal of Treatment - correct answer ✔✔Control Group (between subjects)
Multiple pretest, treatment, Multiple post test, withdrawal, posttest
helps us to draw conclusions about the treatment being what is causing changes
, Single Subject Experiments (n) - correct answer ✔✔a study where you gather information from
only one person/animal
Single-subjects Tradition - correct answer ✔✔individual subjects are essentially equal and most
variability is due to external influences of the situation, but that can be controlled.
Individual Differences Tradition - correct answer ✔✔The idea that most of the differences in
subjects is intrinsic and therefore inevitable. The variability can be measured and statistically
controlled.
What are the Advantages of Single-subject Experiments - correct answer ✔✔Focus more on
individual behavior
Focuses on big effect sizes (magnitude of difference)
Avoid ethical and practical problems
Flexibility in design; can accommodate individual differences
What are the Disadvantages of Single-Subject Experiments - correct answer ✔✔Harder to
detect small effects
less statistical procedures available
Difficult to control extraneous variables
limited external validity
verified answers passed
Quasi-Experimental Designs - correct answer ✔✔Aims to establish a cause-and-effect
relationship between an independent and dependent variable. Groups already exist.
Characteristics of a Quasi-Experiment - correct answer ✔✔No random assignment (still assigned
to groups, just not randomly)
Often no control over treatments (groups already exist)
Problems with Quasi-Experiments - correct answer ✔✔Pre-existing differences between groups
creates a lack of equivalence
Manipulated Independent variable and group membership is confounded (because participants
are assigned to conditions based on group members
Quasi-experiment: Single factor design without manipulation - correct answer ✔✔One
Independent variable/membership
levels of the IV are pre-existing
Example: like a political party/contrasting views
Quasi-experiment: Single factor design with manipulation - correct answer ✔✔Two groups of
subjects assigned to two different conditions
,Independent Variable confounds with group membership
Quasi-experiment: Mixed Factorial Design With Manipulation - correct answer ✔✔One
Between-subjects group, Independent variable is not manipulated
One within subjects experimental group where the Independent variable is manipulated.
Mixed factorial design with manipulation example - correct answer ✔✔Breast fed vs Formula
fed babies spend time with dad, how does that influence attachment?
Breast fed vs formula fed - between subjects, not manipulated
Both groups will have 10 or 20 minutes with dad - within subjects, amount of time each group
gets is manipulated.
Quasi Experimental Designs: Nonequivalent-Control Group Design - correct answer ✔✔There is
an experimental and a control group that were naturally existing (no random assignment so
they're not equal) and you just observe the changes over time
Quasi Experimental Designs: Delayed Control Group - correct answer ✔✔Pre and post testing of
the control group does not happen at the same time as the experimental group, this usually
happens when both groups are not accessible at the same time.
Desired Results for Non-equivalent Control Group Design - correct answer ✔✔Pretest starts off
different
Experimental group changes and control does not
,Uninterpretable results for nonequivalent control group design - correct answer ✔✔Control
group is higher or lower at ceiling/floor effect you do not know if it is possible for them to
change during the experiment
Control group could also just naturally change due to maturation or pre-testing effects even if
they don't receive the treatment
Interrupted Time Series Design - correct answer ✔✔Tracks ONE group over time looking at
before and after treatment to see effects as a result of when treatment was introduced
Pretest, pretest, pretest (sets base line), Treatment, post test (tells us if there is actually a
difference compared to our base line)
Multiple Time-Series Design - correct answer ✔✔Both a control and experimental group receive
multiple pre-test, the treatment, and then multiple post tests.
Same as interrupted time series design except there is a control group.
Repeated Treatment Design - correct answer ✔✔Control Group (between subjects)
Pre-test, treatment, post-test; Pre-test2, treatment, Post-test2
Withdrawal of Treatment - correct answer ✔✔Control Group (between subjects)
Multiple pretest, treatment, Multiple post test, withdrawal, posttest
helps us to draw conclusions about the treatment being what is causing changes
, Single Subject Experiments (n) - correct answer ✔✔a study where you gather information from
only one person/animal
Single-subjects Tradition - correct answer ✔✔individual subjects are essentially equal and most
variability is due to external influences of the situation, but that can be controlled.
Individual Differences Tradition - correct answer ✔✔The idea that most of the differences in
subjects is intrinsic and therefore inevitable. The variability can be measured and statistically
controlled.
What are the Advantages of Single-subject Experiments - correct answer ✔✔Focus more on
individual behavior
Focuses on big effect sizes (magnitude of difference)
Avoid ethical and practical problems
Flexibility in design; can accommodate individual differences
What are the Disadvantages of Single-Subject Experiments - correct answer ✔✔Harder to
detect small effects
less statistical procedures available
Difficult to control extraneous variables
limited external validity
