A one-tailed test is also known as a directional hypothesis ... the sample is $18.75 and the sample standard deviation is $6, can any inference be made about the difference in the average ...

Investopedia / Xiaojie Liu A one-tailed test ... the difference between both observations is statistically significant, and the null hypothesis is rejected. Following our example above, if the ...

Two-sample t ... A paired t-test (also known as a dependent or correlated t-test) is a statistical test that compares the averages/means and standard deviations of two related groups to determine if ...

Two-sample t-tests are statistical tests used to compare the means of two populations. Also known as Student’s t-tests, their results are used to determine if there is a significant difference between ...