What is the role of hypotheses in theory-testing research according to the chapter?

In theory-testing research, hypotheses are deduced predictions about how variables would be interrelated if the theory were valid. They are tested through systematic data collection and analysis by comparing observed outcomes with hypothesized ones. Repeated failure to disconfirm the hypotheses lends support to the theory.

According to the chapter, when quantitative researchers test an existing theory, they deduce implications from it and develop hypotheses, which are predictions about the manner in which variables would be interrelated if the theory were valid. These hypotheses are then subjected to testing through systematic data collection and analysis. The testing process involves comparing observed outcomes with those hypothesized, thereby continually subjecting the theory to potential disconfirmation. If studies repeatedly fail to disconfirm the theory, it gains support. The chapter also emphasizes that theory-testing studies are most useful when researchers devise logically sound deductions, design studies that reduce the plausibility of alternative explanations, and use methods that assess the theory's validity under heterogeneous situations so competing theories can be ruled out.