Experimental designs Flashcards
Contrast effect
unconscious bias that happens when two things are judged in comparison to one another
Counterbalancing
-matching treatment conditions overtime
-researchers might consider all possible orders in experiment
-order in how you expose participants to iv
-ex. show them tv then give them food, or give them food then show them tv
-second will always be worse than the first due to fatigue
Fatigue effect
-not sure if results are bc participant exhausted from repeating design
Independent groups design
-in experimental design where 2 groups are designed to 2 dif conditions
-rely on random assignment
- dif participants are assigned to dif levels of iv
-need 12 participants
Latin square
matrix of n elements (letters) where each element appears exactly once in each column and in each row
Matched pairs design
-They match participants on a key variable, ex. they create pairs of participants
-They randomly assign one of each pair to one level of the independent variable
When is matching usually used?
-when only a few participants are available
-when it is very costly to run large numbers of people in the experiment
(infrequently used)
Mortality
the state or condition of being subject to illness, decline, and death
Order effect
occurs when participants’ responses in the various conditions are affected by the order of conditions to which they were exposed
Posttest-only design
almost the same as classic experimental design, except it does not use a pretest.
Practice effect
participants perform a task better in later conditions because they have had a chance to practice it
Pretest-posttest design
measure the effect of an intervention or treatment on an outcome variable by comparing the scores of the same participants before and after the exposure
Repeated measures design
a design that consists of the same subjects that take part in all circumstances of the independent variable
Selection differences
a kind of error that occurs when the researcher decides who is going to be studied. It is usually associated with research where the selection of participants isn’t random (i.e. with observational studies such as cohort, case-control and cross-sectional studies)
