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sampling. Under area sampling we first divide the total area into
                                           a  number  of smaller  non-overlapping  areas,  generally  called
                                           geographical clusters, then a number of these smaller areas are
                                           randomly selected, and all units in these small areas are included in
                                           the sample. Area sampling is helpful where we do not have the list
                                           of the population concerned. It also makes the field interviewing
                  ◆ Based on               more efficient since interviewer can do many interviews at each
                geographical areas         location. In a study where we are trying to find out socio-economic
                                           status in a Taluk, then we need to take the map of the Taluk and
                                           lay  out  a  grid  with  lines  of  equal  intervals.  Say  if  we  get  50
                                           equal squares that mean we have 50 areas. We can exclude non-
                                           residential areas in the area. Put sequential numbers to all other
                                           squares. Make a house count in each area, say 40 households and
                                           the total sample required is 320. In this case, we need to study 8
                                           squares (area) {320/40=8}. If we study all the households in these
                                           8 areas we can attain the required sample.
                                             E. Multi stage sampling
                                             Where sampling is carried out in multiple numbers of stages it

                  ◆ Multiple stages        is called multi-stage sampling. In order to draw the final sample,
                                           a researcher does a stage-by-stage selection and finally arrives at
                                           the required number of respondents. This is a further development
                                           of the idea of cluster sampling. This technique is meant for big
                                           inquiries extending to a considerably large geographical area like
                                           an entire country.
                                             For example, in a study of employees in the service sector in
                                           Kerala,  the  researcher  in  the  first  stage  may  select  the  service
                                           sector  which  he  intends  to  study, say banks and  insurance. At
                                           the next stage, the kind of institutes are identified, say National,
                                           State or local banks and then at the third stage, the respondents are
                                           selected from the institutions identified at the second stage. This
                                           method helps in identifying samples very systematically covering
                                           the entire population. It saves time, money and labour as it can
                                           concentrate on small areas.
                                           2.1.4.2 Non- Random Sampling or Non-Probability Sampling
                  ◆ Unequal chance for       When  probability  sampling  ensures  equal  chance  for  each
                selection                  element  to  be  selected,  non-probability  sampling  doesn’t  offer
                                           equal chance of selection to each element in the population. There
                                           are  various  methods  adopted  under  this  technique  discussed  as
                                           under.
                                             A. Purposive or judgement sampling
                                             Under this method the researcher fixes a predetermined criteria
                                           and selects  a sample  which matches  the  said criteria  alone  as
                                           sample. The selection of the sample depends on the judgement
                                           of the researcher. For example, a teacher may select only those
                                           who he/she thinks would be aspiring for CA in order to conduct


                 60      SGOU - SLM -MCom Research Methodology
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