Type I and Type II Errors
Because the decision to reject or fail to reject Ho is fully inferential in nature (being based on sample data), there is always the possibility that a Type I or Type II error will be committed. You need to keep this in mind as you read technical research reports, as most researchers do not allude to the possibility of inferential error as they present their results or discuss their findings. In certain cases, the researcher simply presumes that you know that a Type I or Type II error may occur whenever a null hypothesis is tested. In other cases, the researcher unfortunately may have overlooked this possibility in the excitement of seeing that the statistical results were congruent with his or her research hypothesis.
Consider Excerpt 10.30 [not shown here]. The researchers associated with this study deserve high praise for indicating their findings may have been the result of inferential error. With full clarity, they point out that they may have made a Type I error and/or a Type II error. Frankly, I wish there were some sort of law that forced researchers to follow the example shown here.
(From Chapter 10, p. 256)
Copyright © 2012
Schuyler W. Huck