After observing the initial subject, the researcher asks for assistance from the subject to help identify people with a similar trait of interest. The process of snowball sampling is much like asking your subjects to nominate another person with the same trait as your next subject. The researcher then observes the nominated subjects and continues in the same way until the obtaining sufficient number of subjects.
For example, if obtaining subjects for a study that wants to observe a rare disease, the researcher may opt to use snowball sampling since it will be difficult to obtain subjects.
It is also possible that the patients with the same disease have a support group; being able to observe one of the members as your initial subject will then lead you to more subjects for the study.
Check out our quiz-page with tests about:. Retrieved Sep 14, from Explorable. The text in this article is licensed under the Creative Commons-License Attribution 4. You can use it freely with some kind of link , and we're also okay with people reprinting in publications like books, blogs, newsletters, course-material, papers, wikipedia and presentations with clear attribution. Don't have time for it all now? First, we need to try and find one or more units from the population we are studying i.
Finding just a small number of individuals willing to identify themselves and take part in the research may be quite difficult, so the aim is to start with just one or two students i. Due to the sensitivity of the study, the researcher should ask the initial students who agreed to take part in the research to help identify other students that may be willing to take part.
For ethical reasons, these new research participants should come forward themselves rather than being identified by the initial students. In this respect, the initial students help to identify additional units that will make up our sample. The process continues until sufficient units have been identified to meet the desired sample size. Snowball sampling is a useful choice of sampling strategy when the population you are interested in studying is hidden or hard-to-reach.
Snowball sampling is useful in such scenarios because:. It can be difficult to identifying units to include in your sample, perhaps because there is no obvious list of the population you are interested in. For example, there are no lists of drug users or prostitutes that a researcher could get access to, especially lists that could be considered representative of the population of drug users or prostitutes.
The sensitivity of coming forward to take part in research is more acute in such research contexts. Individuals that are drug users or prostitutes, for example, are likely to be less willing to identify themselves and take part in a piece of research than many other social groups.
However, since snowball sampling involves individuals recruiting other individuals to take part in a piece of research, there may be common characteristics, traits and other social factors between those individuals that help to break down some of the natural barriers that prevent such individuals from taking part. Strata are simply sub-groups within a population.
In the case of drug users, it may be obvious to identify strata such as gender i. Whilst is it typical to define the characteristics of the sample you want to examine at the start of the research process, the snowball sample may also be helpful in exploring potentially unknown characteristics that are of interest before settling on your sampling criteria.
Inferential statistics were also used to determine whether the distributions for age and the time it took for a field worker to locate a nominee speed were significant and whether the respective snowballs were drawn from populations with the same distributions.
The second question was seen as especially appropriate for and "ascending" sampling strategy because it cannot be assumed that each snowball is drawn from the same population when only an "imperfect sampling frame" composed of a "special list" compiled by nominees, is available.
Two-tailed KS tests were performed on the pooled data of the three samples one-sample test and on the between-snowballs subgroups data two-samples test. Virtual snowball sampling is a variation of traditional snowball sampling and it relies on virtual networks of participants. It brings new advantages but also disadvantages for the researcher. Virtual snowball sampling technique was used in order to find participants for the study of a minority group - Argentinian entrepreneurs living in Spain.
About 60 percent of this population has double nationality — both Spanish and Argentinian. Spanish national statistics classifies them as European citizens only and there is no information about the place of birth tied to the profiles of entrepreneurs in Spain either. Therefore, referring to national statistics only, made it impossible to build a sample frame for this research.
The use of virtual networks in this example of hard to reach population, increased the number of participating subjects and as a consequence, improved the representativeness of results of the study. Ethical concerns prevented the research staff from directly contacting many potential respondents, consequently program directors or personnel who knew of possible respondents would make initial contacts and then ask those who were willing to cooperate to personally contact the project.
In each instance, the newly recruited research assistant had to be trained to understand and accept the eligibility criteria of the research, which often was difficult because it violated some commonsense understandings concerning treatment and nontreatment. In a qualitative research, apprehension around feelings of compulsion are reviewed for potential ethical dilemmas and recommendations for research process are made.
Snowball sampling is a recruitment method that employs research into participants' social networks to access specific populations. According to research mentioned in the paper written by Kath Browne,  using social networks to research is accessible. In this research, Kath Browne used social networks to research non-heterosexual women. Snowball sampling is often used because the population under investigation is hard to approachable either due to low numbers of potential participants or the sensitivity of the topic.
The author indicated the recruitment technique of snowball sampling, which uses interpersonal relations and connections within people. Due to the use of social networks and interpersonal relations, snowball sampling forms how individuals act and interact in focus groups, couple interviews and interviews.
As a result, snowball sampling not only results in the recruitment of particular samples, use of this technique produces participants'accounts of their lives. To help mitigate these risks, it is important to not rely on any one single method of sampling to gather data about a target sector. In order to most accurately obtain information, a company must do everything it possibly can to ensure that the sampling is controlled.
Also, it is imperative that the correct personnel is used to execute the actual sampling, because one missed opportunity could skew the results. A new approach to the study of hidden populations. It is effectively used to avoid bias in snowball sampling. Respondent-driven sampling involves both a field sampling technique and custom estimation procedures that correct for the presence of homophily on attributes in the population. The respondent-driven sampling method employs a dual system of structured incentives to overcome some of the deficiencies of such samples.
Like other chain-referral methods, RDS assumes that those best able to access members of hidden populations are their own peers. Peer Esteem Snowballing is a variation of snowball sampling, useful for investigating small populations of expert opinion.
Its proponents  argue that it has a number of advantages relative to other snowballing techniques:. From Wikipedia, the free encyclopedia. For other uses, see Snowball disambiguation. This list is incomplete ; you can help by expanding it. This section is written like a research paper or scientific journal that may use overly technical terms or may not be written like an encyclopedic article.
Please help improve it by rewriting it in an encyclopedic style.
In sociology and statistics research, snowball sampling (or chain sampling, chain-referral sampling, referral sampling) is a nonprobability sampling technique where existing study subjects recruit future subjects from among their acquaintances.
Snowball sampling involves primary data sources nominating another potential primary data sources to be used in the research.
Snowball sampling is a non-probability sampling technique that is used by researchers to identify potential subjects in studies where subjects are hard to locate. Jul 05, · ACCESS DENIED. For access to the following page, please contact [email protected] Someone from our team will be in touch with you shortly.
Many activist investors pour in tons of research and express their opinions about the valuation of a company in their filing. Typically, this information is not available in public domain. We have a dedicated page which tracks and monitors such information. However, since snowball sampling involves individuals recruiting other individuals to take part in a piece of research, there may be common characteristics, traits and other social factors between those individuals that help to break down some of the natural barriers .