E N D
1. 5:57 AM The Two-Group Randomized Experiment
2. 5:57 AM The Basic Design R X O
R O note that a pretest is not necessary in this design -- Why?
because random assignment assures that we have probabilistic equivalence between groups
3. 5:57 AM The Basic Design R X O
R O
4. 5:57 AM The Basic Design R X O
R O differences between groups on posttest indicate a treatment effect
usually test this with a t-test or one-way ANOVA
5. 5:57 AM Internal Validity R X O
R O
6. 5:57 AM Experimental Design Variations the posttest-only two group design is the simplest -- there are many variations
to better understand what the variations try to achieve we can use the signal-to-noise metaphor
7. 5:57 AM Signal to Noise
8. 5:57 AM Signal to Noise
9. 5:57 AM Signal to Noise
10. 5:57 AM Signal to Noise
11. 5:57 AM Signal to Noise
12. 5:57 AM Signal to Noise
13. 5:57 AM Signal to Noise
14. 5:57 AM Signal to Noise
15. 5:57 AM Signal to Noise
16. 5:57 AM Signal to Noise factorial designs
covariance designs
blocking designs
17. 5:57 AM