statistical tests

Using a parameter {statistic, test} can test {test, statistics} {statistical tests} whether two sample groups from population are similar.

statistic

Statistic can be mean or variance.

hypothesis

Hypothesis is false if it leads to contradiction, and then hypothesis opposite is true. Assume groups have no difference for statistic {null hypothesis, statistical test}. Try to reject null hypothesis.

significance

Choose allowable probability {significance level, test}, usually 5%, that rejected hypothesis is actually true {type-one error, test} or that accepted hypothesis is actually false {type-two error, test}.

calculation

Calculate probability that sample group is from population.

comparison

Reject hypothesis if probability is less than 5%. The statistic {two-tailed test, error} can be too high and/or too low, the usual case. The statistic {one-tailed test} can be too low or too high. It is hard to prove hypotheses true, but hypotheses are false if they lead to contradiction, thus proving hypothesis opposite.

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3-Statistics-Tests

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Technical Information

Date Modified: 2022.0224