What design? Analyze the design of each research
example reported. Is it a sample survey, an observational
study, or an experiment? If a sample, what are the popula-
tion, the parameter of interest, and the sampling procedure?
If an observational study, was it retrospective or prospective?
If an experiment, describe the factors, treatments, randomi-
zation, response variable, and any blocking, matching, or
blinding that may be present. In each, what kind of conclu-
sions can be reached?A soft-drink manufacturer must be sure the bottle caps
on the soda are fully sealed and will not come off easily.
Inspectors pull a few bottles off the production line at
regular intervals and test the caps. If they detect any
problems, they will stop the bottling process to adjust or
repair the machine that caps the bottles.
