Qualitative research is most often used in academic pursuits such as in sociology, but is also commonly employed in marketing research. This type of research involves collecting information that can not be expressed in numerical values. Qualitative research is often labor intensive, as its methods for collecting information can involve multiple trials and lengthy interviews.
Question those closest to hand. One example of a way to obtain qualitative research is to take a convenience sample. This is perhaps the easiest and least labor-intensive of the sampling methods, as it uses the materials most available to the researcher; the people around him. The researcher would simply ask passing pedestrians questions on the street and record their answers. However, this method of collecting data can often lack credence in the intellectual community and show a great deal of bias while gathering data that may be lacking in quality. To simplify the problem, subjects walking into an upscale department store may give vastly different answers than others visiting a mass merchant such as Walmart.
Identify your target sample. This method of sampling is the most common for research purposes. The person collecting the research will select the most useful sample population to answer the questions that she needs for her research. This method uses public knowledge of political views, beliefs or other identifying characteristics to select the sample and can be the most intellectually accepted. The researcher will separate the samples into different groups and then randomly select one of these groups for research. This allows for the use of a large sample size in order to reduce the risk that there is sampling bias and will allow the researcher to better analyze outliers.
Set your demographics. Quota sampling is a common practice utilized by researchers. In this sampling method, the researcher will determine how many people with a certain characteristic like gender or race to include in each sample when designing the research criteria. Other characteristics may include marital status, profession, household income, geographical area of residence, use of contraceptive method or health status. This separation allows the researcher to choose which group of people she is most interested in studying. The researcher will then go into cities and communities for individuals that fit these criteria until the quota previously set is met.
Use your interviewees as resources. Snowball sampling, also known as chain-referral sampling, is a method of collecting qualitative research from new people using the referrals of the people who have already been included in the study. The previous participants are asked if they know anyone who may have some kind of helpful insight or information that may help the researcher. If they do, then the researcher is put in contact with that person. This technique is often used to access people who are a part of a "hidden population" or those that are often not represented in other samples.