STUDY GUIDE / EXPERT VERIFIED FOR GUARANTEED
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Experiment - ANSWER-a study in which at least one variable is manipulated and
the other is measured
manipulated variable - ANSWER-independent variable - controlled, such as by
assigning participants to its different levels
How many levels must a manipulated variable have? - ANSWER-at least 2
measured variable - ANSWER-dependent variable - take the form of records of
behaviors or attitudes, such as self-reports, behavioral observations or
physiological measures
condition - ANSWER-one of the levels of the independent variable in an
experiment
independent variable - ANSWER-manipulated variable
dependent variable - ANSWER-measured variable
Where is the independent variable usually found on a graph? - ANSWER-the x-
axis
Where is the dependent variable usually found on a graph? - ANSWER-the y-axis
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,control variable - ANSWER-any variable that an experimenter holds constant on
purpose
What do control variables help establish? - ANSWER-INTERNAL validity
What do control variables allow researchers to do? - ANSWER-eliminate
alternative explanations for results
Can experiments support causal claims? - ANSWER-yes, they establish
covariance, temporal precedence, and internal validity
Covariance - ANSWER-Indicated by a different in the group means
comparison group - ANSWER-a group in an experiment whose level on the
independent variable differs from those of the treatment group in some intended
and meaningful way
control group - ANSWER-a level of an independent variable that is intended to
represent "no treatment" or a neutral condition
treatment group - ANSWER-participants of an experiment who are exposed to the
level of the independent variable that involves a medication, therapy, or
intervention
placebo group - ANSWER-exposed to an inert treatment, such as a sugar pill
How can experiments establish temporal precedence? - ANSWER-Researchers
manipulate the independent variable to ensure it comes first in time
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, What are the 2 threats to internal validity of experiment? - ANSWER-1. design
confounds
2. selection effects
Confounds - ANSWER-a potential alternative explanation for a research finding (a
threat to internal validity)
Design confound - ANSWER-a second variable that happens to vary
systematically along with the independent variable and therefore is an alternative
explanation for the results
What happens if there is a design confound? - ANSWER-the study has poor
internal validity and cannot make a causal claim
systematic variability - ANSWER-levels of a variable coincide in some predictable
way with experimental group membership (CONFOUND)
unsystematic variability - ANSWER-levels of a variable fluctuate independently of
experimental group membership, contributing to variability within groups (NOT A
CONFOUND)
In an experiment, all those in the longhand notetaking group were interested in the
lectures, and all those in the laptop group were uninterested.
What is this an example of? - ANSWER-systematic variability (a design confound)
Unsystematic variability can make it difficult to: - ANSWER-detect difference in
the dependent variables
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