0.7. Experimental design

Question 1

Independent measures

Answer 1

Ppts only take part in 1 condition
- random allocation must happen -> all target population into a hat and the first 10 do condition 1, next 10 names out the hat do condition 2

Question 2

strength of independent measures

Answer 2

+ only 1 set of materials needed, no order effects, decreases chance of demand characteristics

Question 3

Weakness of independent measures

Answer 3

More ppts needed (than repeated measures), individual differences slows data

Question 4

Repeated measures

Answer 4

Ppts take part in both conditions (repeat)

Question 5

Strengths of repeated measures

Answer 5

+ fewer ppts needed (than repeated measures)
+no individual differences (same person used)

Question 6

Weaknesses of repeated measures

Answer 6

• demand characteristics (as do both conditions)
• order effects: fatigue/practice (can be reduced by counter balancing AB/BA
• more materials required

Question 7

Matched pairs

Answer 7

Ppts are matched in one variable (e.g. IQ) in a pre-test before the 2nd name out goes into condition 2
Pairs results are compared

Question 8

Strengths of matched pairs

Answer 8

+ no order effects (only 1 set of materials needed)

Question 9

Weaknesses of matched pairs

Answer 9

• time consuming, no 2 people are the same , no demand characteristics, no order effects

Question 10

What is an experimental design?

Answer 10

How people are used in the study