Pre-empirical Research

Done before making observations, including clarifying the meaning of the concepts used in the research, the operational definitions of the variables, and methodological issues, such as identifying the research participant pool and ethics of the procedures.

Descriptive Methods

Research using quantitative methods to describe phenomena as they exist. Aim is to not manipulate or control. Main examples are:

• Naturalistic observation
• Survey research
• Correlational research

Experimental Methods

These are quantitative methods which aim to manipulate and control variables in order to establish cause-and-effect relationships. Main categories of experimental methods are:

• Quasi-experimental designs
• True experimental designs
• Meta-analysis
• Single-subject designs
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Qualitative Methods

Using primarily data from in-depth interviews and other qualitative data to identify and describe the underlying themes of the experience of a phenomenon. Among the many qualitative methods are:

• Naturalistic Inquiry
• Hermeneutic Analysis
• Participant observation
• Ethnography

(Note: the last two methods may also use some quantitative data, but are primarily qualitative.)

Evaluation Research

I have put this in as its own category because its orientation is different enough. The purpose of Evaluation Research is decision-making: should we do this program, how should we do it, did it work, should it be funded, etc.?

Evaluation research can use any of the previous methods.