Research Methods Knowledge Base

by Prof William M.K. Trochim hosted by


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Yin-Yang Map

kbhome.gif (6416 bytes)

You can use the figure above to find your way through the material in the Knowledge Base. Click on any part of the figure to move to that topic.

The figure shows one way of structuring the material in the Knowledge Base. The left side of the figure refers to the theory of research. The right side of the figure refers to the practice of research.

The yin-yang figure in the center links you to a theoretical introduction to research on the left and to the practical issue of how we formulate research projects on the right.

The four arrow links on the left describe the four types of validity in research. The idea of validity provides us with a unifying theory for understanding the criteria for good research. The four arrow links on the right point to the research practice areas that correspond with each validity type. For instance, external validity is related to the theory of how we generalize research results. Its corresponding practice area is sampling methodology which is concerned with how to draw representative samples so that generalizations are possible.