Ch. 10 - Repeated Measures

Question 1

repeated measures design

Answer 1

participants experience ALL levels of an IV.
the DV is measured more than once.
AKA WITHIN SUBJECTS

Question 2

advantages of repeated measures designs

Answer 2

FEWER participants required
MORE POWER = detects better results
can be measured OVER TIME

Question 3

disadvantages of repeated measures

Answer 3

unique situations can only be experienced ONCE
order effects: DECREASE internal validity

Question 4

order effects

Answer 4

1. practice: performance is better due to past practicing
2. fatigue: performance is worse due to cognitive exhaustion and tiring-out
3. carryover: effects of one level of IV carry over to the next, and the remaining effects (cups of coffee)
4. sensitization: act differently towards a level of IV after EXPOSURE to another (light sensitivity)

Question 5

counterbalancing (within, across, reverse)

Answer 5

controls order effects
- within-subjects: one single person does all combinations
- across-subjects: all combos are represented by a distribution across participants
* complete: each participant experiences 1 (rare, 3 or less conditions)
* partial: presents a subset of possible orders and each participant can experience many (3+)
- reverse: ALL subjects do it once ABC, then one CBA.

Question 6

washout period

Answer 6

a brief wait time between levels of IV to ensure no order effects occur.