Focus of the Research Unit
• Research Design
What is Validity?
• the best available approximation to the truth or
falsity of a given inference, proposition,
• a set of standards by which research can be
Types of Validity
conclusion • is there a relationship?
internal • is the relationship causal?
construct • is it the theoretical
relationship we’re interested
external • will it hold for other persons,
What is Research Design?
• the structure of your research project
• tells how the different parts are related
Types of Designs
– Nonequivalent Group Design
– Regression-Discontinuity Design
– Interrupted Time Series Design