Survey

A series of verbal questions or a questionnaire used to gather data about consumer attitudes or behavior.
Surveys of human populations and institutions are common in political polling and government, health, social science and marketing research. A survey may focus on opinions or factual information depending on its purpose, and many surveys involve administering questions to individuals. When the questions are administered by a researcher, the survey is called a structured interview or a researcher-administered survey. When the questions are administered by the respondent, the survey is referred to as a questionnaire or a self-administered survey.

There are several ways of administering a survey, including:

Telephone

• use of interviewers encourages sample persons to respond, leading to higher response rates.
• interviewers can increase comprehension of questions by answering respondents' questions.
• fairly cost efficient, depending on local call charge structure
• good for large national (or international) sampling frames
• cannot be used for non-audio information (graphics, demonstrations, taste/smell samples)
• three types:
• traditional telephone interviews
• computer assisted telephone dialing
• computer assisted telephone interviewing

Mail

• the questionnaire may be handed to the respondents or mailed to them, but in all cases they are returned to the researcher via mail.
• cost is very low, since bulk postage is cheap in most countries
• long time delays, often several months, before the surveys are returned and statistical analysis can begin
• not suitable for very complex issues
• no interviewer bias introduced
• large amount of information can be obtained: some mail surveys are as long as 50 pages
• response rates can be improved by using mail panels
• members of the panel have agreed to participate
• panels can be used in longitudinal designs where the same respondents are surveyed several

Online surveys

• can use web or e-mail
• web is preferred over e-mail because interactive HTML forms can be used
• often inexpensive to administer
• very fast results
• easy to modify
• response rates can be improved by using Online panels - members of the panel have agreed to participate
• if not password-protected, easy to manipulate by completing multiple times to skew results
• data creation, manipulation and reporting can be automated
• data sets created in real time
• some are incentive based

Personal in-home survey

• respondents are interviewed in person, in their homes (or at the front door)
• very high cost
• suitable when graphic representations, smells, or demonstrations are involved
• suitable for long surveys
• suitable for locations where telephone or mail are not developed

Personal mall intercept survey

• shoppers at malls are intercepted - they are either interviewed on the spot, taken to a room and interviewed, or taken to a room and given a self-administered questionnaire
• socially acceptable - people feel that a mall is a more appropriate place to do research than their home
• potential for interviewer bias
• fast
• easy to manipulate by completing multiple times to skew results

Source: http://en.wikipedia.org/wiki/Statistical_survey