In marketing research, both quantitative and qualitative research is important. The two kinds of research are, however, good for very different things. A marketing researcher should be sure to use each kind appropriately.
Quantitative research typically involves looking at large data sets and gleaning objective facts from those sets. Let us imagine that you are working in marketing for an auto manufacturer. You might look at data sets to see what the range of income is for people who buy a given model of car. You might look to see whether they tend to be male or female. You might look at how much education they have. You might look at their driving habits. All of this is data that is objective. A marketing researcher should use quantitative data to answer questions like “how many,” “when,” “where,” and “how often.”
By contrast, qualitative research garners data that is not so objective. It is better for answering questions like “why” and “how.” A person doing marketing for an auto maker might ask focus group researchers to find out why people like a certain model of car. They might ask the researchers to find out how they go about making their buying decisions. These are things that are not really quantifiable and objectively measurable.
Thus, quantitative research should be used to find objective information such as the demographics of a particular market. Qualitative research, by contrast, should be used to gain a deeper understanding of how consumers make their decisions and what leads them (or could lead them) to buy a given product.