Quantitative research is conducted for the purpose of obtaining empirical evaluations of attitudes, behavior or performance. It is designed to generate projectable numerical data about a topic. We use this form of research to answer the questions "how many" or "how much." This type of research is based on the principal that the characteristics of a randomly selected group of people (sample) will closely reflect the characteristics of the entire group (population) from which the sample was taken.
You would want to use this type of research if you wanted to know, for example, what percentage of adults aged 25-40 lease their car or say, you want to know the average height and weight of female 10th graders. The answers to these questions can be either continuous (i.e height) or discrete (i.e. the number of pets you own).
The main type of quantitative research is surveys or questionnaires.
Surveys and Questionnaires
A survey or questionnaire consists of a set of questions, usually close-ended, meaning it includes a set of pre-listed answers. It is designed to get data (figures) regarding a particular topic. Surveys and questionnaires can be conducted via mail, phone, Internet or in-person. Usually, they are relatively short in length.