1. Design of Experiments Jim Bohan Manheim Township School District

2. Three Requirements Comparison Randomization Replication
Groups that are a similar as possible.
How do we make groups as similar as possible?
Randomization
Minimize the effect of confounding influences and lurking variables by spreading these effects equally throughout the groups.
Replication
Is the sample size sufficient so that the differences in responses is due to treatments and not chance?

3. Two Major Designs
Completely Randomized Design
Randomized Block Design

4. Completely Randomized Design
Example:
Random
Assignment Treatment Results
Treatment Results Compare
Control Results

5. Randomized Block Design
Example:
Random Assignment
Treatment Results
Block Compare
Treatment Results
Compare
Block Compare