What is the purpose of multiple testing?
Multiple testing refers to any instance that involves the simultaneous testing of more than one hypothesis. If decisions about the individual hypotheses are based on the unad- justed marginal p-values, then there is typically a large probability that some of the true null hypotheses will be rejected.
What is the highest possible p value?
0.05
A p-value higher than 0.05 (> 0.05) is not statistically significant and indicates strong evidence for the null hypothesis. This means we retain the null hypothesis and reject the alternative hypothesis. You should note that you cannot accept the null hypothesis, we can only reject the null or fail to reject it.
What does t test tell you?
A t-test is a type of inferential statistic used to determine if there is a significant difference between the means of two groups, which may be related in certain features. A t-test looks at the t-statistic, the t-distribution values, and the degrees of freedom to determine the statistical significance.
When to use the two sample t test?
The two-sample t -test (Snedecor and Cochran, 1989) is used to determine if two population means are equal. A common application is to test if a new process or treatment is superior to a current process or treatment. There are several variations on this test. The data may either be paired or not paired.
How to determine if two population means are equal?
Test if two population means are equal. The two-sample t-test (Snedecor and Cochran, 1989) is used to determine if two population means are equal.
Can a test be paired or not paired?
There are several variations on this test. The data may either be paired or not paired. The variances of the two samples may be assumed to be equal or unequal. In some applications, you may want to adopt a new process or treatment only if it exceeds the current treatment by some threshold.
Is the variance of two samples equal or unequal?
The variances of the two samples may be assumed to be equal or unequal. Equal variances yields somewhat simpler formulas, although with computers this is no longer a significant issue.