Quiz 6 Flashcards
maturation threat
a change in behavior that emerges spontaneously, overtime
history threats
historical events change how data comes out
attrition threats
a reduction in participant numbers from pretest to posttest. Only problematic when systematic
testing threats
a type of order effect in which there is a change in participants as a result of experiencing the DV (the test) more than once. Their scores might go up due to practice (practice effect) or go down due to fatigue (fatigue effect)
instrumental threats
occurs when measuring instrument changes over time, observers sometimes change their observation criteria overtime
regression threats
a statistical concept in which extremely low or extremely high performance at Time 1 is less extreme at Time 2
interrogating null effects
sometimes experiment just doesn’t work
weak manipulation
not enough of a difference between the groups
ceiling/floor effects
not seeing a difference because everyone got really high or really low scores
individual differences
spread out scores within each group can cause one score to sway the results
individual differences solutions
- change designs to a within-groups or matched groups design, 2. add more participants
interaction effet
occurs when the effect of one IV depends on the level of another IV, is there a difference in differences, more important than main effects
main effect with three IVs
simple overall difference that examines the effect of one IV averaged across the other two IVs
for a three-way interaction to be significant
means that the two-way interaction between two of the IVs depends on the level of the third IV
participant variable
cannot be manipulated, is treated as an IV in a factorial design
results to interpret when analyzing a factorial study with two IVs
two main effects and one interaction
main effect
is there an overall difference?
