In research methods, what is a "survey" most commonly used for?

A survey is most commonly used for asking people questions to gather data. Surveys are a popular research method designed to collect a variety of information from a specified population. They often consist of structured questionnaires that can include both closed and open-ended questions. The primary goal of surveys is to understand opinions, behaviors, demographics, and other data from respondents, making them a valuable tool for researchers across many fields.

Surveys allow for the collection of large amounts of data efficiently and can provide insights into trends or patterns within the population. This method is particularly advantageous because it enables researchers to reach many participants, often through various mediums like online questionnaires, interviews, or telephone calls.

In contrast, the other options describe different methods or focuses that do not align with the primary function of surveys. Controlled experiments typically involve manipulating variables in a controlled setting rather than just asking questions. While surveys can collect qualitative data, they are not exclusive to that purpose; they also gather quantitative data. Measuring physical characteristics pertains to physical measurement methods, not surveys, which focus on gathering subjective data from individuals.