9 Experimental Research Flashcards
experiment
when you modify something in a situation, then compare an outcome to what existed without the modification
random assignment
a method for assigning cases to groups, each case has a known chance of being selected
matching
matching cases in groups based in certain characteristics, ex. age, sex
pre-test
a measurement of the dependent variable prior to introduction of the treatment
post-test
a measurement of the dependent variable after the treatment has been introduced
control group
does not receive the treatment
experimental group
group that receives the treatment, or in which the treatment is present
selection bias
threat that research participants will not form equivalent groups
history effects
threat that an event unrelated to the treatment will occur during the experiment and influence the dependent variable
maturation
threat that some biological, psychological, or emotional process within the subjects will change over time
instrumentation
when the instrument or dependent variable measure changes during the experiment
statistical regression
tendency for random errors to move group results towards the average
diffusion of treatment aka contamination
the threat that research participants in different groups will communicate with each other and learn about the others’ treatment
hawthorne effect
an effect from the attention of the researchers, reactivity
placebo
false treatment, has no effect
