Professor Tyler wrote a proposal to study the impact of authoritarianism on child rearing practices. She began her research by reviewing the meaning of authoritarianism. Based on this review, she formulated her own definition of authoritarianism. This process illustrates:

conceptualization

Explanation:

Based on the information provided within the question it can be said that this process best illustrates the concept known as conceptualization. This term refers to when an individual performs the action or process of creating a concept or idea of something for themselves. Which is exactly what Professor Tyler has done by reading the definition of authoritarianism in order to create his own thoughts and use those thoughts to then form his own stance or idea on the subject.