Design of Experiments
Choice of Factors
Fill in the Blanks
1. The factors that are actually selected for study in an experiment are called __________ factors.
2. Factors that may influence the response but are not of primary interest are called __________
factors.
3. Some useful classes of factors in experimental design include design factors, nuisance factors,
and __________-__________ factors.
4. __________-__________ factors are factors whose levels are kept fixed during the experiment.
5. Factors that are not held constant and are intentionally changed during the experiment are called
__________ to __________ factors.
6. Some nuisance factors are deliberately held at specific levels so that they become
__________-__________ factors.
7. Other nuisance factors may be intentionally __________ to __________ during the experiment.
8. When nuisance factors vary naturally and cannot be controlled, they are referred to as
__________ factors.
9. It is usually assumed that the effects of __________-__________ factors are relatively small.
10. In experimental studies, __________ factors are variables that may exert some effect on the
response and are deliberately manipulated.
Answer Key
1. design
2. nuisance
3. held-constant
4. held-constant
5. allowed to vary
6. held-constant
7. allowed to vary
8. noise
9. held-constant
10. design