Sample Survey Methods:

If proposed investigation is done  only on  a part taken  out of  universe then it  will be  known  as sample  survey. This  part of the universe is known  as sample. The result obtained by  investing a part of the universe should  also be applicable in  case of that universe. It is not essential  to investigate  the every individual item of the  universe.

By this  methods time is  saved  more  over it is economy. It is to be  noted that if  the  universe is small  sample  survey  is not  necessary  for investigation.

Advantages

Less Time: Since  sample is only  a part of the  population in sample  survey considerable time  and labor are saved. Time  is also  saved  in collection and processing  data. Since  volume of  data is  small.

Less Cost : In  sample  survey we study  only on a part of the  population and the  total  expense of collecting data  is less than that required in census methods

Accurate Information : In sampling we can get more  accurate information.

Reliable Results : Few statistical  errors that might occur can be minimized as the data  collected and processed is relatively small. Presence of sampling errors can be  estimated and controlled with  great precision

Economical  Methods : If complete enquiry  is not  necessary for any investigation then it  would be simply a wastage to make the complete enumeration. In  that case sampling is to be done.

Scientific : If  population  is based  on hypothesis  as in the  case of tossing  a coin or throwing a dice for  any number of times sampling is the  only scientific  methods of estimating the  character  of  population.

Disadvantage

If the  sample is not  draw  properly the results  thus  obtained  may be  files  inaccurate and  misleading

Chances of sampling errors  are great. The investigators personal  bias regarding  the choice of  techniques  and drawings of sample may lead to opposite result.

The size of sample  may not be  sufficient  to representative of the universe.

If the universe is small sample survey is unnecessary.

In absence  of qualified and trained investigators results obtained  from  sample  survey not be accepted.