A t-test is any statistical hypothesis test in which the test statistic follows a Student's t-distribution under the null hypothesis. It can be used to determine if two sets of data are significantly different from each other.
A t-test is most commonly applied when the test statistic would follow a normal distribution if the value of a scaling term in the test statistic were known. When the scaling term is unknown and is replaced by an estimate based on the data, the test statistics (under certain conditions) follow a Student's t distribution.
The one sample t-test, a statistical method of analysis, compares the mean with a hypothesized value and assumes the sample was selected randomly from a population with a normal distribution.
Results are often described with the mean and standard deviation.
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