Thus, this method is also called as the referral sampling method or chain sampling method. Heterogeneity sampling is, in this sense, almost the opposite of modal instance sampling. Snowball sampling may be defined as a technique for gathering research subjects through the identification of an initial subject who is used to provide the names of other actors. The central problem is that these so called global surveys are usually performed on a series of nationally defined and bounded samples. Goodmans formulation requires an initial sample drawn using a probability method on a known sampling frame. It is used where potential participants are hard to. In this blog you will read about the types and method of snowball sampling along with its advantages and disadvantages. This is a sampling technique in which existing subjects provide referrals to recruit samples required for a research study. The purposive sampling technique, also called judgment sampling, is the deliberate choice of an informant due to the qualities the informant possesses. Snowball sampling or chainreferral sampling is defined as a a nonprobability sampling technique in which the samples have traits that are rare to find. The number of people you have access to snowballs as you get in contact with more people. Snowball sampling problems and techniques of chain referral sampling patrick blernackl sun francisco state university dan waldorf pacific institute for research and evaluation nowball or chain referral sampling is a method that has s been widely used in qualitative sociological research. Snowball sampling is a commonly employed sampling method in qualitative research. This article explains a what snowball sampling is, b how to create a snowball sample, and c the advantages.
Snowball sampling is undertaken when a qualified participant shares an invitation with other subjects similar to them who fulfill the qualifications defined for the targeted population berg, 2006. Jan 26, 2017 judging by the numbers of views these two posts have accumulated it is clear that there is a demand for this type of discussion in a clear and concise manner. A researcher using snowball sampling can keep participants anonymous in published papers. It is used where potential participants are hard to find. Snowball sampling is a wellknown, nonprobability method of survey sample selection that is commonly used to locate hidden populations. Snowball definition is a round mass of snow pressed or rolled together. Snowball sampling is a technique where a researcher picks the first few samples and either recruits them or asks them to recommend other subjects they know who fit the description of samples needed. Target populations, sampling frames, and coverage error. From the listed the researcher has to deliberately select items to be sample. This often occurs when the population is somehow marginalized, like homeless or formerly incarcerated individuals or those who are involved in illegal activities.
Snowball sampling is a nonrandom sampling method that uses to. Pdf in order to answer the research questions, it is doubtful that researcher should be able to collect data from all cases. It is to this end that today i discuss another very popular method of sampling, known as snowball sampling. Snowball sampling is a special nonprobability method used when. This method relies on referrals from initially sampled respondents to other persons believed to have the characteristic of interest. In sociology and statistics research, snowball sampling or chain sampling, chainreferral sampling, referral sampling is a nonprobability sampling technique where existing study subjects recruit future subjects from among their acquaintances. These actors may themselves open possibilities for an expanding web of contact. For example, if you are studying the level of customer satisfaction among elite nirvana bali golf club in bali, you will find it increasingly difficult. Using social media and targeted snowball sampling to survey a.
Wecanuseprobabilitysamplingtechniquesonlywhenwecanhavea. This article attempts to rectify this methodological neglect. The use of currently enrolled research participants to recruit additional research participants sometimes referred to as the snowball sampling may be approved by the irb under some circumstances. Scholars have posited several anecdotally based recommendations for enhancing the diversity of. The entire process of sampling is done in a single step with each subject selected independently of the other members of the. Snowball sampling snowball sampling may simply be defined as. Broaden definition of who can be in sampling frame idea.
Pengertian secara umum ada dua teknik sampling yang dapat digunakan, yaitu sampling probabilitas yang cenderung bersifat kuantitatif dengan analisis statistik, dan teknik sampling nonprobabilitas yang cenderung bersifat kualitatif. Snowball sampling is a type of convenience sampling method that is usually applied when it is difficult to acquire respondents with. The sampling method used for the survey was snowball sampling. Snowball sampling one method that is becoming increasingly popular to recruit subjects is snowball sampling. If the population is hard to access, snowball sampling can be used to recruit participants via other participants. Its use is primarily in the collection of indepth, qualitative data, perhaps on sensitive topics, where an obvious. Purposive sampling is an informant selection tool widely used in ethnobotany table 1. Scholars have posited several anecdotally based recommendations for enhancing the diversity of snowball samples. Linear snowball sampling is a snowball sampling in which the researcher recruits a single participant, while the second nominee recruits the third participant. The snowball sampling is a nonrandom sampling technique wherein the initial informants are approached who through their social network nominate or refer the participants that meet the eligibility criteria of the research under study.
Snowball sampling is used in this research to reveal every actor involved in each case either directly or indirectly. Jan 27, 2012 the use of virtual sampling was combined with an online questionnaire as a complementary tool for web 2. Snowball sampling definition of snowball sampling by. Snowball sampling is a popular technique among social scientists who wish to work with a population that is difficult to identify or locate. You are researching experiences of homelessness in your city. Snowball sampling research office oregon state university. Munich personal repec archive a manual for selecting sampling techniques in research alvi, mohsin university of karachi, iqra university 23 march 2016 online at mpra paper no.
Unlike convenience samples, research subjects are selected for specific attributes that preliminary research has defined as targets. Snowball sampling is a technique used by researchers primarily when they are researching hidden populations or subcultures such as drug users. A sampling plan is a formal plan specifying a sampling method, a sample size, and procedure for recruiting participants box 1. Purposive sampling as a tool for informant selection. The term snowball is used to represent a sampling method that relies on one participant recruiting friends and acquaintances from. Snowball sampling is a recruitment technique in which research participants are asked to assist researchers in identifying other potential subjects. However, the use of the method is not adequately explained in most studies. Enhancing the sample diversity of snowball samples. Systematic errors can be defined as incorrect or false representation of the sample. Sociology at surrey university of surrey research socialupdate. According to research mentioned in the paper written by kath browne, using social networks to research is accessible.
The variables to which the sample is drawn up are linked to the research question. January 26, 2017 the triangle admin leave a comment. The current participants are asked to recommend new people for the study. Despite the lack of substantive writing on snowball sampling as a method, several authors 2, 3, 21 have provided. Snowball sampling definition in the cambridge english. Snowball sampling also known as chainreferral sampling is a nonprobability nonrandom sampling method used when characteristics to be possessed by samples are rare and difficult to find. This definition can initially seem selfexplanatory, which may explain why. Snowball sampling social research update university of surrey. Using this approach, a few potential respondents are contacted and asked whether they know of anybody with the characteristics that you are looking for in your research. Snowball sampling is a sampling technique to gather data or information from a specific group of people 27 and mostly used to study hidden population 28. Nonprobability sampling research methods knowledge base.
Snowball sampling is a nonprobability sampling technique that is used by researchers to identify potential subjects in studies where subjects are hard to locate. The procedures of chain referral sampling are not selfevident or obvious. Enhancing the sample diversity of snowball samples plos. Its called snowball sampling because in theory once you have the ball rolling, it picks up more snow along the way and becomes larger and larger. Used to choose the number of participants, interviews, or work samples to use in the assessment process. Engaging marginalized populations in holistic research abstract womanist and feminist qualitative researchers continue to identify research methods and techniques that harness the power of social networking and personal connections while. Surveys of housing units, where an individual is asked who lives in the house, frequently misses some people. In snowball sampling, you begin by identifying someone who meets the criteria for inclusion in your study. Simple random sampling systematic random sampling stratified random sampling cluster sampling probability sampling methods compared nonprobabilitysamplingmethods availability sampling quota sampling purposive sampling snowball sampling lessonsaboutsamplequality generalizabilityinqualitative. Aug 22, 2018 snowball sampling is a commonly employed sampling method in qualitative research. Sampling procedure 1 of 2 sampling procedure definition sample. The use of virtual sampling was combined with an online questionnaire as a complementary tool for web 2. You then ask them to recommend others who they may know who also meet the criteria.
Thus the sample group is said to grow like a rolling snowball. Snowball sampling is a type of nonprobability sampling technique. Snowball sampling article about snowball sampling by the. There are many many different ways to develop your sampling strategy. A manual for selecting sampling techniques in research 4 preface the manual for sampling techniques used in social sciences is an effort to describe various types of sampling methodologies that are used in researches of social sciences in an easy. The snowball sampling is a research technique through survey and data. Division of academic and student affairs office of assessment sampling procedure 1 of 2 sampling procedure definition sample. This paper focuses on snowball sampling procedures, which we define as those actions undertaken to initiate, progress and terminate the snowball sample 1, 20. This is not therefore a random sample and no inferences about the characteristics of the parent population can be made from such a study.
Using social media and targeted snowball sampling to. As the sample builds up, enough data are gathered to be useful for research. Snowball sampling is where research participants recruit other participants for a test or study. For example, if you are studying the level of customer satisfaction among elite nirvana bali golf club in. The article provides a description and analysis of some of the problems that were encountered and resolved in the course of using the method in a relatively large exploratory study of exopiate addicts. Sampling process may encounter the problem of systematic errors and sampling biases. Simple random sampling in this technique, each member of the population has an equal chance of being selected as subject. Quota sampling, accidental sampling, judgemental sampling or purposive sampling, expert sampling, snowball sampling, modal instant sampling. Researchers use this sampling method if the sample for the study is very rare or is limited to a very small subgroup of the population. In this research, kath browne used social networks to research nonheterosexual women.
Yin 2011 deciding on issues for the quintain stake, 2005b theore1cal samplingongoing sampling merriam, 2009 used to sample within the case a ongoing sampling is less emphasized in phenomenology or case study. Snowball sampling is a recruitment method that employs research into participants social networks to access specific populations. Nonprobability sampling focuses on sampling techniques that are based on the judgement of the researcher see our article nonprobability sampling to learn more about nonprobability sampling. For example, many sexual assault survivors are reluctant to talk about their experiences and avoid identifying themselves as survivors. In the past i have spoken about some of these in detail, for example i mention and discuss from a holistic perspective. Snowball sampling is defined as a nonprobability sampling technique in which the samples have traits that are rare to find. Media and targeted snowball sampling 282 ples and the asystematic recruitment of research subjects in convenience samples on the one hand and the more rigid cluster and stratified samples on the other.
Types of nonprobability random sampling quota sampling. Pdf snowball sampling is a wellknown, nonprobability method of survey sample selection that is commonly used to locate hidden. Dec 04, 2018 the snowball sampling method is extensively used where a population is unknown and rare and it is tough to choose subjects to assemble them as samples for research. One subject gives the researcher the name of another subject, who in turn provides the name of a third, and so on vogt, 1999. Snowball sampling is an approach for locating informationrich key informants1. A manual for selecting sampling techniques in research. One subject gives the researcher the name of another subject, who in turn. Yin 2011 deciding on issues for the quintain stake, 2005b theore1cal sampling ongoing sampling merriam, 2009 used to sample within the case a ongoing sampling is less emphasized in phenomenology or case study. Broaden the definition of who can be in the sampling frame, then screen out as necessary incurs extra costs and requires additional effort example. Stratified sampling selfselection sampling cluster sampling snowball sampling probability sampling 1. Comparision of snowball sampling and sequential sampling. A qualitative sampling plan describes how many observations, interviews, focusgroup discussions or cases are needed to ensure that the findings will contribute rich data. Insights from an overview of the methods literature abstract the methods literature regarding sampling in qualitative research is characterized by important inconsistencies and ambiguities, which can be problematic for students and researchers seeking a clear and coherent understanding.