In natural sciences and social sciences, * quantitative* research is the systematic empirical investigation of observable phenomena via statistical, mathematical, or computational techniques. The objective of quantitative research is to develop and employ mathematical models, theories, and/or hypotheses pertaining to phenomena.

The process of measurement is central to quantitative research because it provides the fundamental connection between empirical observation and the mathematical expression of quantitative relationships. Quantitative data is any data that is in numerical form such as statistics, percentages, etc. In layman’s terms, this means that the quantitative researcher asks a specific, narrow question and collects a sample of numerical data from observable phenomena or from study participants to answer the question. The researcher analyzes the data with the help of statistics.

The researcher is hoping the numbers will yield an unbiased result that can be generalized to some larger population. Qualitative research, on the other hand, asks broad questions and collects word data from phenomena or participants. The researcher looks for themes and describes the information in themes and patterns exclusive to that set of participants. In social sciences, quantitative research is widely used in psychology, economics, sociology, marketing, community health, health & human development, gender, and political science, and less frequently in anthropology and history.

Research in mathematical sciences such as physics is also ‘quantitative’ by definition, though this use of the term differs in context. In the social sciences, the term relates to empirical methods, originating in both philosophical positivism and the history of statistics, which contrast with qualitative research methods.

Qualitative methods produce information only on the particular cases studied, and any more general conclusions are only hypotheses. Quantitative methods can be used to verify which of such hypotheses are true. A comprehensive analysis of 1274 articles published in the top two American sociology journals between 1935 and 2005 found that roughly two-thirds of these articles used quantitative methods.