Dissertation methodology will discuss about the methods those you are going to implement to complete your research project. After selection of a topic and making a workable hypothesis you have to decide whether census or sample survey needs to be implemented for collection of data.
Sample survey method has definite advantage over census method of collecting information from several stand points-
1) Sample survey takes less time, labor and money than is necessary in complete enumeration, because only a part of the whole population is investigated. In most cases, time and money is available for the completion of an investigation is limited, and as such it becomes necessary to employ sample survey method.
2) There is greater scope in sample survey than in census. In the former, only a small group of skilled investigators is employed for the collection of information. Although the cost per investigator is larger in sample survey than in census, because of the specialized training to be imparted to these personnel, the amount of information collected by each is much larger. As such, a larger geographical area can be covered and more intensive data collection can be made in sample survey with the same amount of money spent in census.
3) Sample survey yields more precise results than census, because of the deployment of specially trained investigators and the possibility of better control and supervision over them. Census necessitates a large army of investigators all of whom can’t be expected to have the same standards of skill, intelligence and efficiency. Sample survey no doubt introduces sampling error, but non sampling errors are practically absent here. On the other hand, although in the census method, there is no question of sampling error( because the whole population is investigated), yet large magnitudes of non sampling errors affect the accuracy of results more severely than the sampling errors introduced in a sample survey.
4) An extra advantage of sample survey method is that the magnitude of error is known. Sample survey depends on the laws of probability, and as such the magnitude of sampling errors can be theoretically calculated. Since non sampling errors do not follow any definite probability law, no such estimate of error is possible in census method.
5) In some cases, complete enumeration is not feasible and sample survey method is the only way. For example, a rice merchant can’t afford to examine every single grain of rice he purchases. He has to depend only on a sample based on which he forms an idea about the quality of rice in the whole consignment.
Because of these advantages, random sampling and various other sampling techniques are getting very popular now a day. After selecting the sampling techniques the data needs to be collected from the field and then this collected data will go through different analytical treatment and finally you can reach at the conclusion. At the time of following dissertation methodology you need to be totally unbiased towards the subject and need to be totally free from any kind of preconceived notions.