Week 3 Simple Between

Question 1

How many IV/s do simple between subjects designs have?

Answer 1

1 IV

Question 2

What are the simple between experimental designs?

Answer 2

• Randomized, post test-only, control group design
• Randomized, pretest-post test, control group design
• Multilevel, completely randomized between subjects design
• Soloman four-group design

Question 3

What is the randomized, post test-only, control group design?Advantages and Disadvantages

Answer 3

Experimental and control groups
GE        X          O
GC                    O
regression and attribution reduced (RA)
history and maturation reduced due to control group
RA ensures stat equivalence

Question 4

What is the randomized, pretest-post test, control group design? Advantages and Disadvantages

Answer 4

Experimental and control group with pretest
GE O X O
GC O O
more certain of stat equivalence before treatment
Advantages of pretest:
- ^ sensitivity
- identification of ceiling effects (wrong measurement tool etc)
- initial position of DV may interact with exp condition
- S’s are initially comparable on relevant variables
- evidence of change
Disadvantages:
- increase time & money required
- may sensitize S’s to experimental treatment condition

Question 5

What is the multilevel, completely randomized between subjects design? Advantages and Disadvantages

Answer 5

Extension of randomized, pretest-post test control group design.
G1      O         X1        O
G2     O         X2       O
G3     O         X3       O  
ETC

Question 6

What is the soloman four-group design? Advantages and Disadvantages

Answer 6

Combines randomized, post test-only, control group design and randomized, pretest-post test, control group design.
G1 O X1 O
G2 O O
G3 X3 O
G4 O
Advantages:
- R/A = group equivalence at start, also controls confounding due to stat reg
- include control G2 controls history and maturation
- G3 control interaction of effects of pretest
- G4 further control for maturation

Question 7

What is the critical comparison of simple between subjects designs?

Answer 7

Subjects in one group against different subjects in another group. (independent of each other)