What Student-t is
Student-t is a statistical test used to compare two sets of data. It is used to determine if there is a statistically significant difference between the means of two groups.
The steps for a Student-t test are as follows:
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State the null hypothesis. Typically, the null hypothesis states that there is no difference between the means of the two groups.
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Calculate the degrees of freedom. This is the number of data points in each group minus one.
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Calculate the t-statistic. This is done by subtracting the mean of one group from the mean of the other group and dividing by the standard error.
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Calculate the critical value. This is done by looking up the t-statistic in a t-table with the appropriate degrees of freedom.
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Compare the calculated t-statistic to the critical value. If the t-statistic is greater than the critical value, then the null hypothesis is rejected. If the t-statistic is less than the critical value, then the null hypothesis is accepted.
Examples
- Student-t tests are commonly used to compare the means of two independent groups.
- Student-t tests are often used to determine whether a sample has a mean that is statistically different from a known population mean.
- Student-t tests can be used to determine if there is a significant difference between the means of two independent samples.
- Student-t tests are used to compare the means of three or more independent groups.
- Student-t tests are used to test for differences in variance between two or more groups.