The correct solution for this question is statement 1: "When conducting pairwise tests, it's necessary to use a procedure, such as Holm's correction, to maintain the family-wise error rate."
Let's break this down step by step.
1. When we perform multiple pairwise tests, there's always a probability of getting at least one significant result purely by chance.
2. This issue, known as the family-wise error rate, is the probability of making one or more false discoveries, or type I errors, among all the hypotheses when performing multiple comparisons.
3. Since a pairwise comparison test involves conducting many separate tests simultaneously, the chances of observing significant results just due to random errors increases. This increasing family-wise error rate can lead to unreliable results or incorrect inferences.
4. To control for the family-wise error rate, it's necessary to implement a suitable correction method like Holm's correction.
5. Holm's correction is a method used to counteract the problem of multiple comparisons. It's an adjusted version of the Bonferroni correction and is also known as the Holm–Bonferroni method. The Holm's procedure lowers the family-wise error rate, ensuring that statistical results are more reliable and the conclusions drawn from the analysis are valid.
Upon taking into account all of these factors, it's clear that statement 1 is true: When conducting pairwise tests, it really is necessary to use procedures, such as Holm's correction, to maintain the family-wise error rate. This is an essential step to improve the reliability of our statistical analyses.