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Mathematics, 15.10.2020 08:01 latiamason16
The essential difference between an experiment and an observational study is that:
a. Observational studies may have confounded variables, but experiments never do.
b. In an experiment, people must give their informed consent before being allowed to participate.
c. Observational studies are always biased.
d. Observational studies cannot have response variables.
e. An experiment imposes treatments on the subjects, but an observational study does not.
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The essential difference between an experiment and an observational study is that:
a. Observational...
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