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statistical tests. <><><><><><>
Depending on the experiment, expectation can be very powerful. In a medical experiment, a control group can help determine whether the drug being tested is responsible for the result rather than expectation or something else. For a study of a rare occurrence, a control group may help an experimenter determine whether the outcome is due to chance.
Research
For maintaining reliability internally, a researcher will use as many repeat sample groups as possible, to reduce the chance of an abnormal sample group skewing the results. If you use three replicate samples for each manipulation, and one generates completely different results from the others, then there may be something wrong with the experiment.
statistical tests
line graphs
line graphs
statistical tests
statistical tests
statistical tests. <><><><><><>
statistical tests. <><><><><><>
replication
replication
statistical tests
statistical tests. <><><><><><>
Statistically the larger the sample size the more significant the results of the experiment are. Chance variation is ruled out.