PSYC 255 Exam 3 And 4: Liberty
University Latest Questions with
Actual Complete Answers 2025-2026
Edition.
causal claim - Answer boldest claim a scientist can make
- makes, influences, affects
- states something about interventions or treatments
- experiments are the only way to investigate these
Intervention - Answer ultimate goal of psychological studies and they must be based on sound
experimental research
covariance, temporal precedence, internal validity - Answer 3 rules of causation
control group - Answer level of independent variable that is intended to represent "no
treatment" or neutral condition (not needed in every experiment, but comparison group is
needed)
treatment group - Answer other levels or levels of an independent variable
confounds - Answer possible explanations/ threats to internal validity (confuse)
design confound - Answer experimenter's mistake in designing the independent variable
- occurs when a second variable happens to vary systematically along with the intended
independent variable
systematic variability and unsystematic - Answer (random/ haphazard) - can obscure, the
dependent variable (not confound)
selection effects - Answer when the kinds of participants in one level of the independent
variable are systematically different than those in the other
- or when participants choose which group they want to be in
, random assignment - Answer avoid selection effects (equal chance)
- de-systematizing the types of participants who end up in each level
matched groups - Answer researchers assign participants at random to one condition or
another in an experiment
- requires more time and research (GPA, demographics, etc)
manipulation checks - Answer extra dependent variable that researchers can insert into an
experiment to convince them that their experimental manipulation worked
- help determine whether operationalization worked as intended
pilot study - Answer simple study, using separate group of participants, that is completed
before or after the study of primary interest to confirm effectiveness of manipulations
original units - Answer used when you want to estimate the real-world impact of an
intervention
standardized effect size - Answer correlation coefficient "r" :used when you want to compare
effect sizes that are based on different units or enables you to compare the results found in one
study to a body of knowledge
- When two groups in an experiment = "d" = takes into account both the difference between
means and the spread of scores within each group (standard deviation)
d - Answer 0.2 = small
0.5 = moderate
0.8 = large
experiment - Answer researchers manipulated one variable and measured another
manipulated variable - Answer variable that is controlled or when researchers assign
participants to a level of the variable
- Independent Variable (only one)
- X-axis
University Latest Questions with
Actual Complete Answers 2025-2026
Edition.
causal claim - Answer boldest claim a scientist can make
- makes, influences, affects
- states something about interventions or treatments
- experiments are the only way to investigate these
Intervention - Answer ultimate goal of psychological studies and they must be based on sound
experimental research
covariance, temporal precedence, internal validity - Answer 3 rules of causation
control group - Answer level of independent variable that is intended to represent "no
treatment" or neutral condition (not needed in every experiment, but comparison group is
needed)
treatment group - Answer other levels or levels of an independent variable
confounds - Answer possible explanations/ threats to internal validity (confuse)
design confound - Answer experimenter's mistake in designing the independent variable
- occurs when a second variable happens to vary systematically along with the intended
independent variable
systematic variability and unsystematic - Answer (random/ haphazard) - can obscure, the
dependent variable (not confound)
selection effects - Answer when the kinds of participants in one level of the independent
variable are systematically different than those in the other
- or when participants choose which group they want to be in
, random assignment - Answer avoid selection effects (equal chance)
- de-systematizing the types of participants who end up in each level
matched groups - Answer researchers assign participants at random to one condition or
another in an experiment
- requires more time and research (GPA, demographics, etc)
manipulation checks - Answer extra dependent variable that researchers can insert into an
experiment to convince them that their experimental manipulation worked
- help determine whether operationalization worked as intended
pilot study - Answer simple study, using separate group of participants, that is completed
before or after the study of primary interest to confirm effectiveness of manipulations
original units - Answer used when you want to estimate the real-world impact of an
intervention
standardized effect size - Answer correlation coefficient "r" :used when you want to compare
effect sizes that are based on different units or enables you to compare the results found in one
study to a body of knowledge
- When two groups in an experiment = "d" = takes into account both the difference between
means and the spread of scores within each group (standard deviation)
d - Answer 0.2 = small
0.5 = moderate
0.8 = large
experiment - Answer researchers manipulated one variable and measured another
manipulated variable - Answer variable that is controlled or when researchers assign
participants to a level of the variable
- Independent Variable (only one)
- X-axis
