experimental design

Question 1

independent groups

Answer 1

Two separate groups are involved, each group does one of the conditions of the experiment.

Question 2

repeated measures

Answer 2

All participants take part in all conditions of the experiment.

Question 3

matched pairs

Answer 3

Participants are matched on some variable that is important to the experiment and then one of each pair is allocated to a different condition.

Question 4

random allocation

Answer 4

An attempt to evenly distribute participant differences across experimental conditions in an independent group design.

Question 5

counterbalancing

Answer 5

An attempt to control for order effects in a repeated measures design: half the participants do the conditions in one order and the other half in the opposite order.

Question 6

2 limitation independent groups

Answer 6

ppts who occupy groups not the same in ppt variables, differences due to ppts and not IV, counfounding variables.
use random allocation

less economical, contributes single result, x2 ppts needed to produce same data as matched pairs. more money and time

Question 7

strenght of independent groups

Answer 7

order effects not a problem, less likely to guess aims too.

Question 8

2 limitations repeated measures

Answer 8

each ppt 2 tasks min, order effects.
boredom and fatigue causes deterioration in 2nd task, or skills improve, confounding variable
use counterbalancing

more likely to work out aim of the study when experience all conditions, demand characteristics

Question 9

strength of repeated measures

Answer 9

ppts controlled, higher validity, fewer are also needed, saving time and money.

Question 10

2 limitations matched pairs

Answer 10

ppts can never be matched exactly, still important differences that my affect the DV

time-consuming and expensive process of matching ppts, esp if pre-test requires

Question 11

strength matched pairs

Answer 11

ppts only take part in single condition, order effects and demand characteristics limited.