Experimental Research Flashcards
(15 cards)
Causation
Requires correlation, temporal precedence, and eliminate 3rd variables
Correlation
the relationship between two variables
temporal precedence
cause comes before the effect; an experiment does this by manipulating the IV
eliminate 3rd variables
we get this through experimental control, and if successful we have strong internal validity
manipulation
change variable to create multiple conditions, also called levels of independent variable.
measurement
the dependent variable is measured for each condition
controlled variables
Held constant across levels of the independent variable because it is a suspected confound. In a perfect scenario, all other variables are controlled or are the same between conditions.
extraneous variables
a variable that is not controlled, manipulated, or measured.
experimental control
a set of tools to allow an experimenter to eliminate confounds and control potential 3rd variables to ensure that the IV is causing changes in the DV
Tools for eliminating systematic variation/confounds
holding constant, matching, random assignment.
Holding constant
hold the value of a potential confound constant across all levels of the IV, all items have the same value or a restricted range.
Matching
match participants on the confounding variable across levels of the IV, for every level of the IV there’s one person with the same value of the potential confound.
Random assignment
for each participant from the sample, randomly assigned them to a condition.
Control groups
a control group is used to measure the effect on the DV in the absence of the IV allows us to look for one-group threats to validity.
Problems and Solutions of internal validity
Problems - confounds, selection, history, maturation, and testing effects.
Solutions - holding constant, matching, random assignment, control groups.
