or quote someone famous defining it :D
Define descriptive-normative research method?
The Descriptive approach which aims primarily at gathering knowledge (i.e. descriptions and explanations) about the object of study but does not wish to modify the object. The target is to find out how things are, or how they have been.
Normative approach tries to define how things should be, which means that it will be necessary to define also the subjective point of view that shall be used. This approach has sometimes been called "applied research."