{"id":151,"date":"2019-07-30T06:36:28","date_gmt":"2019-07-30T06:36:28","guid":{"rendered":"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/?post_type=chapter&#038;p=151"},"modified":"2019-07-31T04:27:21","modified_gmt":"2019-07-31T04:27:21","slug":"non-probable-sampling-techniques","status":"publish","type":"chapter","link":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/chapter\/non-probable-sampling-techniques\/","title":{"rendered":"Non probable sampling techniques"},"content":{"raw":"<div><span style=\"float: right\"><a href=\"https:\/\/youtu.be\/dzNlhGDIbEY\" target=\"_blank\" rel=\"noopener\"><img src=\"http:\/\/epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/2018\/11\/download.png\" alt=\"epgp books\" width=\"75px\" height=\"75px;\" \/><\/a>\r\n<\/span><\/div>\r\n&nbsp;\r\n\r\n&nbsp;\r\n\r\n&nbsp;\r\n<div>\r\n<p style=\"text-align: justify\">Sampling is not anything, which is followed only in statistics. It is used in everyday life. When rice is purchased in provision store, a small quantity initially purchased and tested. Sometimes, the small quantity is cooked and if it is found good, then the bulk is purchased. There is always difference of opinion in using sampling as the basis for data collection and conclusion. Those who aruge against sampling state that whatever care is taken in selection of sample, cenpercent representation of the population cannot be achieved.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">A sample design is a defined plan for obtaining a sample from a given population. It refers to the technique or the procedure the researches would adopt in selecting items for the sample. Sampling design may as well lay down the number of items to be included in the sample [i.e.] the size of the sample. Sample design is determined before data are collected researcher must select\/prepare a sample design which should be reliable and appropriate for his research study.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><strong>OBJECTIVES OF SAMPLING<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">The main objectives of the sampling are as follows:<\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\">To make an inference about an unknown parameter from a measurable sample statistic.<\/li>\r\n \t<li style=\"text-align: justify\">To test the hypothesis relating to population.<\/li>\r\n \t<li style=\"text-align: justify\">To avoid the vast study about the entire population.<\/li>\r\n \t<li style=\"text-align: justify\">To obtain quick result.<\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">SAMPLING AND ITS ELEMENTS IN THE PROCESS OF SAMPLING<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Sampling is the process of drawing a sample from a larger population or universe. The following three elements are in the process of sampling<\/span><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Selecting the sample<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Collecting the information<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Making an inference about the population<\/span><\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n<p style=\"text-align: justify\"><strong>REASONS FOR USING SAMPLING TECHNIQUES<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">The sampling technique is used for the following reasons:<\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><em>\u00a0<\/em><em>Economy: <\/em>The sampling technique is less expensive than the census technique.<\/li>\r\n \t<li style=\"text-align: justify\"><em>Less time consuming: <\/em>The data can be collected and summarised more quickly by studying a sample than by studying the entire universe. Hence, the sampling technique is less time-consuming than the census technique.<\/li>\r\n \t<li style=\"text-align: justify\"><em>Reliability: <\/em>If the choice of sample units is made with due care and the matter under survey is not heterogeneous, the conclusion of the sample survey will have almost the same reliability as those of census survey<\/li>\r\n \t<li style=\"text-align: justify\"><em>Detailed study: <\/em>Since the number of sample units is fairly small these can be studied intensively and elaborately.<\/li>\r\n \t<li style=\"text-align: justify\">Sampling is a scientific technique.<\/li>\r\n \t<li style=\"text-align: justify\">Greater suitability in most situations is obtained.<\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><strong>CHARACTERISTICS OF A GOOD SAMPLE<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">To obtain worthwhile results by using sampling techniques, the sampling should possess the following characteristics.<\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><em>Representativeness: <\/em>A sample should fully represent the whole data. Hence, the researcher should be careful in selecting those units which have the same set of qualities and features of the population.<\/li>\r\n \t<li style=\"text-align: justify\"><em>Independence: <\/em>All units of the sample should be included independently of one another.<\/li>\r\n \t<li style=\"text-align: justify\"><em>Adequacy: <\/em>The number of units selected as sample should be sufficient to derive conclusions applicable to the whole data.<\/li>\r\n \t<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Homogeneity: <\/em><span style=\"text-align: initial;font-size: 1em\">The units included in sample must have likeness with other units, otherwise sample will be unscientific.<\/span><\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">STEPS TO BE TAKEN TO MAKE THE SAMPLE USEFUL AND RELIABLE <\/strong><span style=\"text-align: initial;font-size: 1em\">The following steps are to be taken in the process of selection of a sample:<\/span><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Defining the population or universe to be surveyed: <\/em><span style=\"text-align: initial;font-size: 1em\">The population to be surveyed has to be defined in terms of element, nature, units, extent and time.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Specifying the sampling frame: <\/em><span style=\"text-align: initial;font-size: 1em\">It is necessary to specify the list of sampling units from which a sample is taken. The researcher has to give the means of representing the elements of the population, such as, telephone directory, map or any other list used for this purpose.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Specifying sampling unit: <\/em><span style=\"text-align: initial;font-size: 1em\">The sampling unit is to be selected, which may contain one or several population elements.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Specifying method of sampling: <\/em><span style=\"text-align: initial;font-size: 1em\">The sampling method used for selecting the sampling units are to be described.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Determining the size of sample: <\/em><span style=\"text-align: initial;font-size: 1em\">The number of elements or units of the population to be sampled is chosen.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Specifying the sampling plan: <\/em><span style=\"text-align: initial;font-size: 1em\">The operational procedure for selection of the sampling units has to be given.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Selection of the sample: <\/em><span style=\"text-align: initial;font-size: 1em\">The selection of the sample is carried out in the field.<\/span><\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">ADVANTAGES OF SAMPLING<\/strong><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Sampling reduces the time and cost of research studies.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It saves the number of staffs required for field work, processing and analysing the data.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It gives much scope for a detailed study.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">By proper selection of the sample accuracy of results can be ensured.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is more convenient than census.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It provides much quicker results than census.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Sampling is more useful, when the number of units is very large and scattered.<\/span><\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">DISADVANTAGES OF SAMPLING<\/strong><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Sampling technique is less accurate than the census technique.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is not scientific to extent the conclusions derived from one set of sample to other sets which are unlike or are changeable.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Faulty method of sampling may lead to biased selection and hence false generalisation.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The sampling technique can be successful only if a competent and able scientist makes the selection. Otherwise the selection is liable to be wrong.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">If the universe is small then it is not possible to make selection of the sample.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">If the population is heterogeneous, then this technique cannot be used.<\/span><\/li>\r\n<\/ul>\r\n<a href=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/chapter\/non-probable-sampling-techniques\/untitled-34\/\" rel=\"attachment wp-att-152\"><img class=\"aligncenter size-full wp-image-152\" src=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-33.png\" alt=\"\" width=\"1165\" height=\"866\" \/><\/a>\r\n\r\n<\/div>\r\n<div>\r\n<p style=\"text-align: justify\"><strong>TYPES OF SAMPLING<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">There are two types in methods of sampling. They are:<\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\">Random sampling&amp; probability sampling<\/li>\r\n \t<li style=\"text-align: justify\">Non-Random or Non-Probable sampling<\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">NON PROBABLE SAMPLING TECHNIQUE<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Non-random or non-probability sampling refers to the sampling process in which, the samples are selected for a specific purpose with a pre-determined basis of selection. This type of sampling is also required at times when random selection may not be possible. Therefore, the reliability of conclusions based on this type of sampling is less. Whenever a researcher uses this type of sampling, he would make a specific mention of it in the thesis, so that the conclusions would be evaluated accordingly.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Non \u2013 probability sampling do not follow the theory of probability in the choice of elements from the sampling population.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Non-probability sampling designs are used when the number of elements in a population is either unknown or cannot be individually identified.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">In such situations the selection of elements is dependent upon other considerations.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">There are four non-random designs each based on a different consideration, which are commonly used in qualitative and quantitative research.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is also known as deliberate purposive or non-random sampling or judgement sampling. In this type of sample items are selected deliberately by researcher. There is no assurance that every element has some specifiable chance of being included.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is not based on the theory of probability. Under this method of sampling, researcher cannot assure that every element has an equal chance of being chosen.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Non-probability or Non-random samplings are of four types. They are<\/span><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Convenience sampling<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Judgement sampling<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Quota sampling<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Snow-ball sampling<\/span><\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n<a href=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/chapter\/non-probable-sampling-techniques\/untitled-35\/\" rel=\"attachment wp-att-153\"><img class=\"aligncenter size-full wp-image-153\" src=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-34.png\" alt=\"\" width=\"837\" height=\"567\" \/><\/a>\r\n\r\n&nbsp;\r\n<p style=\"text-align: justify\"><strong>i.<\/strong><strong>CONVENIENCE SAMPLING:<\/strong><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\">Some times known as grab or opportunity sampling or accidental or haphazard sampling<\/li>\r\n \t<li style=\"text-align: justify\">A type of nonprobability sampling which involves the sample being drawn from that part of the population which is close to hand. That is, readily available and convenient.<\/li>\r\n \t<li style=\"text-align: justify\">The researcher using such a sample cannot scientifically make generalizations about the total population from this sample because it would not be representative enough.<\/li>\r\n \t<li style=\"text-align: justify\">This method is also called as Chunk method. A chunk refers to the fraction of the population to be investigated. This chunk is not selected by probability but selected by judgement or by convenience.<\/li>\r\n \t<li style=\"text-align: justify\">This method of sampling involves selecting the sample elements using some convenient method without going through the rigour of sampling method. The researcher may make use of any convenient base to select the required number of samples.<\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\">FOR EXAMPLE: Sample obtained from readily available list such as car booking, telephone directories, etc. is a convenient sample.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">The results obtained in this method can hardly be representative of the population.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">They are generally biased and unsatisfactory. However, it is often used for pilot studies.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">SUITABILITY: This method is suitable for simple purposes like testing ideas or rough impressions about a subject of interest.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">ADVANTAGES:<\/span><\/p>\r\n\r\n<\/div>\r\n<div>\r\n<ul>\r\n \t<li>It is the cheapest and the simplest method.<\/li>\r\n \t<li>It does not require a list of population.<\/li>\r\n \t<li>It does not require any statistical expertise.<\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\">DISADVANTAGES:<\/p>\r\n\r\n<ul>\r\n \t<li>It is highly biased.<\/li>\r\n \t<li>It is the least reliable sample method.<\/li>\r\n \t<li>The findings cannot be generalized.<\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\">ii.\u00a0\u00a0<strong>JUDGEMENT OR PURPOSIVE SAMPLING:<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">Judgemental sampling is a form of convenience sampling in which the population elements are selected based on the judgement of the researcher or those conform to some criterion of interest.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">The primary consideration in purposive sampling is the judgement of the researcher as to who can provide the best information to achieve the objectives of the study.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">The researcher only goes to those people who in his\/her opinion are likely to have the required information and be willing to share it.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">This type of sampling is extremely useful when you want to construct a historical reality, describe a phenomenon or develop something about which only a little is known.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">It is that method of sampling, in which the samples are drawn on the basis of personal judgement of a person. Generally the researcher uses his judgement in the choice of the samples which he thinks most suitable for his study. While choosing the samples, only the average items are considered and extreme items are omitted.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\">EXAMPLE: Suppose 100 boys are to be selected from a college from 1000 boys. If nothing is known about the students in this college, then the investigator may visit the\u00a0<span style=\"font-size: 1em;text-align: initial\">college and choose the first 100 boys he meets. Or he may select 100 boys all belonging to<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">III\u00a0 year. Or he may select 25 boys from Commerce course, 25 from Science courses, 25 boys from Arts courses and 25 from Fine arts courses. Hence, when only the sample size is known, the investigator uses his discretion and selects the sample.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">SUITABILITY: This method is appropriate when what is important is the typicality and specific relevance of the sampling units to the study and not their overall representatives of the population.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">ADVANTAGES:<\/span><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is less costly and more convenient.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It guarantees inclusion of relevant elements in the sample.<\/span><\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">DISADVANTAGES:<\/span><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">This method does not ensure the representativeness of the sample<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">This method is less efficient than random sampling for generalisation.<\/span><\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">iii.\u00a0<\/strong><strong style=\"text-align: initial;font-size: 1em\">QUOTA SAMPLING<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The main consideration directing quota sampling is the researcher\u2019s ease of access to the sample population<\/span><strong style=\"text-align: initial;font-size: 1em\">.<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The sample is selected from a location convenient to the researcher, and whenever a person with this visible relevant characteristic is seen that person is asked to participate in the study.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The process continues until the researchers have been able to contact the required number of respondents.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">There are advantages and disadvantages with this design.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is one of the commonly used methods of sampling in market surveys and opion polls. Though it is a non-random sampling, it combines the technique of probability sampling and purposive selection. This method is convenient and economical.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">In this method, the quote has to be determined in advance and intimated to the investigator. The quote for each segment of the population may be fixed at random or with a\u00a0<\/span><span style=\"text-align: initial;font-size: 1em\">specific basis. Normally, such a sampling method does not ensure representativeness of the population.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">SUITABILITY: This method is suitable for marketing surveys, opinion poss and readership survey.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">ADVANTAGES:<\/span><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is considerably less costly than probability sampling.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It consumes less time.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">There is no need for a list of population.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Field work can easily be organised.<\/span><\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">DISADVANTAGES:<\/span><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It may not yield a representative sample.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is impossible to estimate the sampling error.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The finding is not generalizable to any significant extent.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is difficult to sample more than three variable dimensions.<\/span><\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">iv.\u00a0\u00a0<\/span><strong style=\"text-align: initial;font-size: 1em\">SNOWBALL SAMPLING:<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Snowball sampling is a special type of non-probability sampling technique through which a respondent list is built-up by using an initial set of its members as informants.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Snowball sampling is the process of selecting a sample using networks.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">To start with a few individuals in a group or organisation are selected and the required information is collected from them.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">They are then asked to identify other people in the group or organisation, and the people selected by them become apart of the sample.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Information is collected from them, and then these people are identified other members of the group and in turn those identified become the basis of further data collection.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The process is continued until the required number or a saturation point has been reached in terms of the information being sought.<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">EXAMPLE 1:<\/span><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Snow ball sampling is a highly specialised method of sampling. It involves starting a process with one individual or group and using their contacts to develop the sample.<\/span><\/p>\r\n\r\n<\/div>\r\n<div>\r\n\r\n<a href=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/chapter\/non-probable-sampling-techniques\/untitled-36\/\" rel=\"attachment wp-att-154\"><img class=\"aligncenter size-full wp-image-154\" src=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-35.png\" alt=\"\" width=\"809\" height=\"807\" \/><\/a>\r\n<p style=\"text-align: justify\">EXAMPLE 2: If a researcher wants to study the problems faced by the Sri Lankan refugees or Refugees from Bangladesh or Burma, he may identify an initial group of refugees through some Government sources like collectorate, embassy and from a list of camp officer. Then he can ask each one of them to supply names of other refugees known to them and continue this procedure until he gets an exhaustive list from which he can draw a sample.<\/p>\r\n\r\n<\/div>\r\n<div>\r\n\r\nEXAMPLE 3:\r\n\r\n<a href=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/chapter\/non-probable-sampling-techniques\/untitled-37\/\" rel=\"attachment wp-att-155\"><img class=\"aligncenter size-full wp-image-155\" src=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-36.png\" alt=\"\" width=\"1003\" height=\"1427\" \/><\/a>\r\n<p style=\"text-align: justify\">SUITABILITY: This method is suitable for a study for which no sample frames are readily available.<\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">ADVANTAGES:<\/span><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"font-size: 1em\">It is useful for smaller populations for which no frames are readily available<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"font-size: 1em\">It is very useful in studying social groups of various kinds.<\/span><\/li>\r\n<\/ul>\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">DISADVANTAGES:<\/span><\/p>\r\n\r\n<ul>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is difficult to apply this method when the population is large.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It does not ensure the inclusion of all elements in the list.<\/span><\/li>\r\n \t<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">This method does not allow the use of probability statistical methods. Elements included are dependent on the subjective choice of the originally selected respondents<\/span><\/li>\r\n<\/ul>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">CONCLUSION<\/strong><\/p>\r\n&nbsp;\r\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Whenever a scientific study is planned it may not always be feasible to study the entire population. In such situation we need to apply some sampling technique to select samples and it\u2019s better to select a non-probability sampling technique which has its own advantages and disadvantages. This type of sampling techniques gives no assurance that every element has some specific chance of being included. It is clear that for the non-probability samples there is no way of calculating the margin of error and the level of confidence. Non-probability sampling procedures are much less desirable and easy to carry out.<\/span><\/p>\r\n\r\n<\/div>\r\n&nbsp;\r\n<table>\r\n<tbody>\r\n<tr>\r\n<td><strong>you can view video on Non probable sampling techniques <\/strong><\/td>\r\n<td><a href=\"https:\/\/youtu.be\/dzNlhGDIbEY\" target=\"_blank\" rel=\"noopener\"><img class=\"alignnone wp-image-120\" src=\"http:\/\/epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/2018\/11\/download.png\" alt=\"\" width=\"36\" height=\"36\" \/><\/a><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<strong>Web links<\/strong>\r\n<ul>\r\n \t<li>http:\/\/dissertation.laerd.com\/non-probability-sampling.php<\/li>\r\n \t<li>http:\/\/www.statisticshowto.com\/non-probability-sampling\/<\/li>\r\n \t<li>https:\/\/explorable.com\/non-probability-sampling<\/li>\r\n \t<li>https:\/\/en.wikipedia.org\/wiki\/Nonprobability_sampling<\/li>\r\n \t<li>https:\/\/www.socialresearchmethods.net\/kb\/sampnon.php<\/li>\r\n<\/ul>","rendered":"<div><span style=\"float: right\"><a href=\"https:\/\/youtu.be\/dzNlhGDIbEY\" target=\"_blank\" rel=\"noopener\"><img decoding=\"async\" src=\"http:\/\/epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/2018\/11\/download.png\" alt=\"epgp books\" width=\"75px\" height=\"75px;\" \/><\/a><br \/>\n<\/span><\/div>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<div>\n<p style=\"text-align: justify\">Sampling is not anything, which is followed only in statistics. It is used in everyday life. When rice is purchased in provision store, a small quantity initially purchased and tested. Sometimes, the small quantity is cooked and if it is found good, then the bulk is purchased. There is always difference of opinion in using sampling as the basis for data collection and conclusion. Those who aruge against sampling state that whatever care is taken in selection of sample, cenpercent representation of the population cannot be achieved.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">A sample design is a defined plan for obtaining a sample from a given population. It refers to the technique or the procedure the researches would adopt in selecting items for the sample. Sampling design may as well lay down the number of items to be included in the sample [i.e.] the size of the sample. Sample design is determined before data are collected researcher must select\/prepare a sample design which should be reliable and appropriate for his research study.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><strong>OBJECTIVES OF SAMPLING<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">The main objectives of the sampling are as follows:<\/p>\n<ul>\n<li style=\"text-align: justify\">To make an inference about an unknown parameter from a measurable sample statistic.<\/li>\n<li style=\"text-align: justify\">To test the hypothesis relating to population.<\/li>\n<li style=\"text-align: justify\">To avoid the vast study about the entire population.<\/li>\n<li style=\"text-align: justify\">To obtain quick result.<\/li>\n<\/ul>\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">SAMPLING AND ITS ELEMENTS IN THE PROCESS OF SAMPLING<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Sampling is the process of drawing a sample from a larger population or universe. The following three elements are in the process of sampling<\/span><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Selecting the sample<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Collecting the information<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Making an inference about the population<\/span><\/li>\n<\/ul>\n<\/div>\n<div>\n<p style=\"text-align: justify\"><strong>REASONS FOR USING SAMPLING TECHNIQUES<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">The sampling technique is used for the following reasons:<\/p>\n<ul>\n<li style=\"text-align: justify\"><em>\u00a0<\/em><em>Economy: <\/em>The sampling technique is less expensive than the census technique.<\/li>\n<li style=\"text-align: justify\"><em>Less time consuming: <\/em>The data can be collected and summarised more quickly by studying a sample than by studying the entire universe. Hence, the sampling technique is less time-consuming than the census technique.<\/li>\n<li style=\"text-align: justify\"><em>Reliability: <\/em>If the choice of sample units is made with due care and the matter under survey is not heterogeneous, the conclusion of the sample survey will have almost the same reliability as those of census survey<\/li>\n<li style=\"text-align: justify\"><em>Detailed study: <\/em>Since the number of sample units is fairly small these can be studied intensively and elaborately.<\/li>\n<li style=\"text-align: justify\">Sampling is a scientific technique.<\/li>\n<li style=\"text-align: justify\">Greater suitability in most situations is obtained.<\/li>\n<\/ul>\n<p style=\"text-align: justify\"><strong>CHARACTERISTICS OF A GOOD SAMPLE<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">To obtain worthwhile results by using sampling techniques, the sampling should possess the following characteristics.<\/p>\n<ul>\n<li style=\"text-align: justify\"><em>Representativeness: <\/em>A sample should fully represent the whole data. Hence, the researcher should be careful in selecting those units which have the same set of qualities and features of the population.<\/li>\n<li style=\"text-align: justify\"><em>Independence: <\/em>All units of the sample should be included independently of one another.<\/li>\n<li style=\"text-align: justify\"><em>Adequacy: <\/em>The number of units selected as sample should be sufficient to derive conclusions applicable to the whole data.<\/li>\n<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Homogeneity: <\/em><span style=\"text-align: initial;font-size: 1em\">The units included in sample must have likeness with other units, otherwise sample will be unscientific.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">STEPS TO BE TAKEN TO MAKE THE SAMPLE USEFUL AND RELIABLE <\/strong><span style=\"text-align: initial;font-size: 1em\">The following steps are to be taken in the process of selection of a sample:<\/span><\/p>\n<ul>\n<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Defining the population or universe to be surveyed: <\/em><span style=\"text-align: initial;font-size: 1em\">The population to be surveyed has to be defined in terms of element, nature, units, extent and time.<\/span><\/li>\n<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Specifying the sampling frame: <\/em><span style=\"text-align: initial;font-size: 1em\">It is necessary to specify the list of sampling units from which a sample is taken. The researcher has to give the means of representing the elements of the population, such as, telephone directory, map or any other list used for this purpose.<\/span><\/li>\n<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Specifying sampling unit: <\/em><span style=\"text-align: initial;font-size: 1em\">The sampling unit is to be selected, which may contain one or several population elements.<\/span><\/li>\n<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Specifying method of sampling: <\/em><span style=\"text-align: initial;font-size: 1em\">The sampling method used for selecting the sampling units are to be described.<\/span><\/li>\n<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Determining the size of sample: <\/em><span style=\"text-align: initial;font-size: 1em\">The number of elements or units of the population to be sampled is chosen.<\/span><\/li>\n<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Specifying the sampling plan: <\/em><span style=\"text-align: initial;font-size: 1em\">The operational procedure for selection of the sampling units has to be given.<\/span><\/li>\n<li style=\"text-align: justify\"><em style=\"text-align: initial;font-size: 1em\">Selection of the sample: <\/em><span style=\"text-align: initial;font-size: 1em\">The selection of the sample is carried out in the field.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">ADVANTAGES OF SAMPLING<\/strong><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Sampling reduces the time and cost of research studies.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It saves the number of staffs required for field work, processing and analysing the data.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It gives much scope for a detailed study.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">By proper selection of the sample accuracy of results can be ensured.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is more convenient than census.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It provides much quicker results than census.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Sampling is more useful, when the number of units is very large and scattered.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">DISADVANTAGES OF SAMPLING<\/strong><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Sampling technique is less accurate than the census technique.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is not scientific to extent the conclusions derived from one set of sample to other sets which are unlike or are changeable.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Faulty method of sampling may lead to biased selection and hence false generalisation.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The sampling technique can be successful only if a competent and able scientist makes the selection. Otherwise the selection is liable to be wrong.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">If the universe is small then it is not possible to make selection of the sample.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">If the population is heterogeneous, then this technique cannot be used.<\/span><\/li>\n<\/ul>\n<p><a href=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/chapter\/non-probable-sampling-techniques\/untitled-34\/\" rel=\"attachment wp-att-152\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-152\" src=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-33.png\" alt=\"\" width=\"1165\" height=\"866\" srcset=\"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-33.png 1165w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-33-300x223.png 300w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-33-768x571.png 768w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-33-1024x761.png 1024w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-33-65x48.png 65w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-33-225x167.png 225w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-33-350x260.png 350w\" sizes=\"auto, (max-width: 1165px) 100vw, 1165px\" \/><\/a><\/p>\n<\/div>\n<div>\n<p style=\"text-align: justify\"><strong>TYPES OF SAMPLING<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">There are two types in methods of sampling. They are:<\/p>\n<ul>\n<li style=\"text-align: justify\">Random sampling&amp; probability sampling<\/li>\n<li style=\"text-align: justify\">Non-Random or Non-Probable sampling<\/li>\n<\/ul>\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">NON PROBABLE SAMPLING TECHNIQUE<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Non-random or non-probability sampling refers to the sampling process in which, the samples are selected for a specific purpose with a pre-determined basis of selection. This type of sampling is also required at times when random selection may not be possible. Therefore, the reliability of conclusions based on this type of sampling is less. Whenever a researcher uses this type of sampling, he would make a specific mention of it in the thesis, so that the conclusions would be evaluated accordingly.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Non \u2013 probability sampling do not follow the theory of probability in the choice of elements from the sampling population.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Non-probability sampling designs are used when the number of elements in a population is either unknown or cannot be individually identified.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">In such situations the selection of elements is dependent upon other considerations.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">There are four non-random designs each based on a different consideration, which are commonly used in qualitative and quantitative research.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is also known as deliberate purposive or non-random sampling or judgement sampling. In this type of sample items are selected deliberately by researcher. There is no assurance that every element has some specifiable chance of being included.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is not based on the theory of probability. Under this method of sampling, researcher cannot assure that every element has an equal chance of being chosen.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Non-probability or Non-random samplings are of four types. They are<\/span><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Convenience sampling<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Judgement sampling<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Quota sampling<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Snow-ball sampling<\/span><\/li>\n<\/ul>\n<\/div>\n<div>\n<p><a href=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/chapter\/non-probable-sampling-techniques\/untitled-35\/\" rel=\"attachment wp-att-153\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-153\" src=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-34.png\" alt=\"\" width=\"837\" height=\"567\" srcset=\"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-34.png 837w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-34-300x203.png 300w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-34-768x520.png 768w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-34-65x44.png 65w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-34-225x152.png 225w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-34-350x237.png 350w\" sizes=\"auto, (max-width: 837px) 100vw, 837px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><strong>i.<\/strong><strong>CONVENIENCE SAMPLING:<\/strong><\/p>\n<ul>\n<li style=\"text-align: justify\">Some times known as grab or opportunity sampling or accidental or haphazard sampling<\/li>\n<li style=\"text-align: justify\">A type of nonprobability sampling which involves the sample being drawn from that part of the population which is close to hand. That is, readily available and convenient.<\/li>\n<li style=\"text-align: justify\">The researcher using such a sample cannot scientifically make generalizations about the total population from this sample because it would not be representative enough.<\/li>\n<li style=\"text-align: justify\">This method is also called as Chunk method. A chunk refers to the fraction of the population to be investigated. This chunk is not selected by probability but selected by judgement or by convenience.<\/li>\n<li style=\"text-align: justify\">This method of sampling involves selecting the sample elements using some convenient method without going through the rigour of sampling method. The researcher may make use of any convenient base to select the required number of samples.<\/li>\n<\/ul>\n<p style=\"text-align: justify\">FOR EXAMPLE: Sample obtained from readily available list such as car booking, telephone directories, etc. is a convenient sample.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">The results obtained in this method can hardly be representative of the population.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">They are generally biased and unsatisfactory. However, it is often used for pilot studies.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">SUITABILITY: This method is suitable for simple purposes like testing ideas or rough impressions about a subject of interest.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">ADVANTAGES:<\/span><\/p>\n<\/div>\n<div>\n<ul>\n<li>It is the cheapest and the simplest method.<\/li>\n<li>It does not require a list of population.<\/li>\n<li>It does not require any statistical expertise.<\/li>\n<\/ul>\n<p style=\"text-align: justify\">DISADVANTAGES:<\/p>\n<ul>\n<li>It is highly biased.<\/li>\n<li>It is the least reliable sample method.<\/li>\n<li>The findings cannot be generalized.<\/li>\n<\/ul>\n<p style=\"text-align: justify\">ii.\u00a0\u00a0<strong>JUDGEMENT OR PURPOSIVE SAMPLING:<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">Judgemental sampling is a form of convenience sampling in which the population elements are selected based on the judgement of the researcher or those conform to some criterion of interest.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">The primary consideration in purposive sampling is the judgement of the researcher as to who can provide the best information to achieve the objectives of the study.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">The researcher only goes to those people who in his\/her opinion are likely to have the required information and be willing to share it.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">This type of sampling is extremely useful when you want to construct a historical reality, describe a phenomenon or develop something about which only a little is known.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">It is that method of sampling, in which the samples are drawn on the basis of personal judgement of a person. Generally the researcher uses his judgement in the choice of the samples which he thinks most suitable for his study. While choosing the samples, only the average items are considered and extreme items are omitted.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\">EXAMPLE: Suppose 100 boys are to be selected from a college from 1000 boys. If nothing is known about the students in this college, then the investigator may visit the\u00a0<span style=\"font-size: 1em;text-align: initial\">college and choose the first 100 boys he meets. Or he may select 100 boys all belonging to<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">III\u00a0 year. Or he may select 25 boys from Commerce course, 25 from Science courses, 25 boys from Arts courses and 25 from Fine arts courses. Hence, when only the sample size is known, the investigator uses his discretion and selects the sample.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">SUITABILITY: This method is appropriate when what is important is the typicality and specific relevance of the sampling units to the study and not their overall representatives of the population.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">ADVANTAGES:<\/span><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is less costly and more convenient.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It guarantees inclusion of relevant elements in the sample.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">DISADVANTAGES:<\/span><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">This method does not ensure the representativeness of the sample<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">This method is less efficient than random sampling for generalisation.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">iii.\u00a0<\/strong><strong style=\"text-align: initial;font-size: 1em\">QUOTA SAMPLING<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The main consideration directing quota sampling is the researcher\u2019s ease of access to the sample population<\/span><strong style=\"text-align: initial;font-size: 1em\">.<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The sample is selected from a location convenient to the researcher, and whenever a person with this visible relevant characteristic is seen that person is asked to participate in the study.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The process continues until the researchers have been able to contact the required number of respondents.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">There are advantages and disadvantages with this design.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is one of the commonly used methods of sampling in market surveys and opion polls. Though it is a non-random sampling, it combines the technique of probability sampling and purposive selection. This method is convenient and economical.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">In this method, the quote has to be determined in advance and intimated to the investigator. The quote for each segment of the population may be fixed at random or with a\u00a0<\/span><span style=\"text-align: initial;font-size: 1em\">specific basis. Normally, such a sampling method does not ensure representativeness of the population.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">SUITABILITY: This method is suitable for marketing surveys, opinion poss and readership survey.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">ADVANTAGES:<\/span><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is considerably less costly than probability sampling.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It consumes less time.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">There is no need for a list of population.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Field work can easily be organised.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">DISADVANTAGES:<\/span><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It may not yield a representative sample.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is impossible to estimate the sampling error.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The finding is not generalizable to any significant extent.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is difficult to sample more than three variable dimensions.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">iv.\u00a0\u00a0<\/span><strong style=\"text-align: initial;font-size: 1em\">SNOWBALL SAMPLING:<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Snowball sampling is a special type of non-probability sampling technique through which a respondent list is built-up by using an initial set of its members as informants.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Snowball sampling is the process of selecting a sample using networks.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">To start with a few individuals in a group or organisation are selected and the required information is collected from them.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">They are then asked to identify other people in the group or organisation, and the people selected by them become apart of the sample.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Information is collected from them, and then these people are identified other members of the group and in turn those identified become the basis of further data collection.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">The process is continued until the required number or a saturation point has been reached in terms of the information being sought.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">EXAMPLE 1:<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Snow ball sampling is a highly specialised method of sampling. It involves starting a process with one individual or group and using their contacts to develop the sample.<\/span><\/p>\n<\/div>\n<div>\n<p><a href=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/chapter\/non-probable-sampling-techniques\/untitled-36\/\" rel=\"attachment wp-att-154\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-154\" src=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-35.png\" alt=\"\" width=\"809\" height=\"807\" srcset=\"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-35.png 809w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-35-150x150.png 150w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-35-300x300.png 300w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-35-768x766.png 768w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-35-65x65.png 65w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-35-225x224.png 225w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-35-350x349.png 350w\" sizes=\"auto, (max-width: 809px) 100vw, 809px\" \/><\/a><\/p>\n<p style=\"text-align: justify\">EXAMPLE 2: If a researcher wants to study the problems faced by the Sri Lankan refugees or Refugees from Bangladesh or Burma, he may identify an initial group of refugees through some Government sources like collectorate, embassy and from a list of camp officer. Then he can ask each one of them to supply names of other refugees known to them and continue this procedure until he gets an exhaustive list from which he can draw a sample.<\/p>\n<\/div>\n<div>\n<p>EXAMPLE 3:<\/p>\n<p><a href=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/chapter\/non-probable-sampling-techniques\/untitled-37\/\" rel=\"attachment wp-att-155\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-155\" src=\"http:\/\/hsp16.epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-36.png\" alt=\"\" width=\"1003\" height=\"1427\" srcset=\"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-36.png 1003w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-36-211x300.png 211w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-36-768x1093.png 768w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-36-720x1024.png 720w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-36-65x92.png 65w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-36-225x320.png 225w, https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-content\/uploads\/sites\/292\/2019\/07\/Untitled-36-350x498.png 350w\" sizes=\"auto, (max-width: 1003px) 100vw, 1003px\" \/><\/a><\/p>\n<p style=\"text-align: justify\">SUITABILITY: This method is suitable for a study for which no sample frames are readily available.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">ADVANTAGES:<\/span><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"font-size: 1em\">It is useful for smaller populations for which no frames are readily available<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"font-size: 1em\">It is very useful in studying social groups of various kinds.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">DISADVANTAGES:<\/span><\/p>\n<ul>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It is difficult to apply this method when the population is large.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">It does not ensure the inclusion of all elements in the list.<\/span><\/li>\n<li style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">This method does not allow the use of probability statistical methods. Elements included are dependent on the subjective choice of the originally selected respondents<\/span><\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><strong style=\"text-align: initial;font-size: 1em\">CONCLUSION<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: justify\"><span style=\"text-align: initial;font-size: 1em\">Whenever a scientific study is planned it may not always be feasible to study the entire population. In such situation we need to apply some sampling technique to select samples and it\u2019s better to select a non-probability sampling technique which has its own advantages and disadvantages. This type of sampling techniques gives no assurance that every element has some specific chance of being included. It is clear that for the non-probability samples there is no way of calculating the margin of error and the level of confidence. Non-probability sampling procedures are much less desirable and easy to carry out.<\/span><\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<table>\n<tbody>\n<tr>\n<td><strong>you can view video on Non probable sampling techniques <\/strong><\/td>\n<td><a href=\"https:\/\/youtu.be\/dzNlhGDIbEY\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-120\" src=\"http:\/\/epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/2018\/11\/download.png\" alt=\"\" width=\"36\" height=\"36\" \/><\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><strong>Web links<\/strong><\/p>\n<ul>\n<li>http:\/\/dissertation.laerd.com\/non-probability-sampling.php<\/li>\n<li>http:\/\/www.statisticshowto.com\/non-probability-sampling\/<\/li>\n<li>https:\/\/explorable.com\/non-probability-sampling<\/li>\n<li>https:\/\/en.wikipedia.org\/wiki\/Nonprobability_sampling<\/li>\n<li>https:\/\/www.socialresearchmethods.net\/kb\/sampnon.php<\/li>\n<\/ul>\n","protected":false},"author":8,"menu_order":24,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":["dr-pa-raajeswari"],"pb_section_license":""},"chapter-type":[],"contributor":[60],"license":[],"class_list":["post-151","chapter","type-chapter","status-publish","hentry","contributor-dr-pa-raajeswari"],"part":3,"_links":{"self":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/pressbooks\/v2\/chapters\/151","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/wp\/v2\/users\/8"}],"version-history":[{"count":3,"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/pressbooks\/v2\/chapters\/151\/revisions"}],"predecessor-version":[{"id":158,"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/pressbooks\/v2\/chapters\/151\/revisions\/158"}],"part":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/pressbooks\/v2\/parts\/3"}],"metadata":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/pressbooks\/v2\/chapters\/151\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/wp\/v2\/media?parent=151"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/pressbooks\/v2\/chapter-type?post=151"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/wp\/v2\/contributor?post=151"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/hsp16\/wp-json\/wp\/v2\/license?post=151"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}