A field worker was instructed to start a snowball sample of a particular trait identified as characteristic of the heroin scene. At the zero stage, the subject selected was asked to nominate other heroin users sharing that trait the maximal number of nominees was From the set of those nominated at each stage, a simple random selection was made of a single individual.
The field worker then attempted to make contact with that nominee. The amount of time in days speed required to make contact was recorded, as well as other specified traits of the individuals e.
Figure 1 graphically shows the traits in this sample in terms or the days it took to find a specific nominee, the operationalization of speed. Sample one was started with a year-old British heroin user whose referrals included a year-old Italian.
After this Italian nominee was selected, it took the field worker 4 days to find him. He then nominated, among others, another Italian, 22 years of age, who was found on the same day.
The randomly selected nominee of this third user was a year-old Belgian who could not nominate another. After subjects were identified, both quantitative and qualitative analyses of the three samples were conducted, and graphic representations of the data were constructed and marked for relevant traits.
Descriptive statistical comparisons were made for the entire dataset as well as for the foreign and prostitute subgroups. 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. 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? No problem, save it as a course and come back to it later. Snowball Sampling Chain Referral Sampling. Share this page on your website: Chain Referral Sampling 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.
This article is a part of the guide: Select from one of the other courses available: The basics , if you are unsure about the terms unit , case , object , sample and population ]. Collectively, all student drug users make up our population. However, we are only interested in examining a sample of these student drug users.
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.
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 .