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Types of Statistical Designs
Experimental designs
- Random allocation of treatments to experimental units
- Drug studies with human subjects
- Agricultural practices on test plots
Observational Studies
- Factor space designs
- Gradient studies
- "Representative" sites studies
- Available site studies
Survey Designs
- Census (every member of population surveyed)
- Probability Surveys (random site selection component)
Response Designs
- Measurement and observational protocols for surveying a site
- Needed in all cases