روش شناسی پژوهش در علوم انسانی

The main objective of this paper is to explore the application of the null and alternative statistical hypotheses in quantitative research. The “null hypothesis” is widely employed in applied, especially experimental, studies in order to accept or reject a hypothesis through the use of inferential statistics by researchers in various branches of the humanities—particularly psychology, educational sciences, management, and sociology. In contrast, the “contrapositive hypothesis” (also known as reductio ad absurdum) is typically employed to establish geometric propositions. It is a provisional assumption from which a contradiction is deduced through logical reasoning. Such a contradiction may negate the assumption of the theorem or that of the contrapositive proof itself. Although the distinct application of these two concepts has been widely addressed in the scientific and academic domain, their interrelation has seldom been discussed. This study seeks to elucidate that connection while also identifying their points of convergence and divergence. One of the key findings indicates that in determining the outcome of the null hypothesis, the researcher encounters various types of error (namely Type I and Type II errors); hence, the term “confirmation” is used. However, in the contrapositive method—being devoid of such errors—the term “reasoning” is more appropriate. The null hypothesis is primarily used in quantitative research adopting a deductive approach within an inferential process dependent on numerical data. Although hypotheses may be defined in qualitative studies, they lack structural rigor and coherence, due to their inductive, subjectivist, and interpretive approach based on oral and narrative data presentation and analysis.