There are two methods which are normally used in collecting information for evaluation.
Census method
Sampling method
In census method, information is collected from all the people or the population involved. However, the method is not very feasible because it may not always be possible to obtain information from all the population. Hence the second method which is sampling is more accurate, easy and is often used.
Sampling method involves selecting a small number from the whole concerned group, from which an estimate can be made for the whole group. The use of sampling implies:
Seeking information from a small number of carefully selected people whose answers and opinion will be representing the whole group.
Saving time and money
Characteristics of detailed and accurate studies as information are obtained from less number of persons.
The sampling method involves drawing the sample in following ways:
List Sampling: A random group of people or any other list of people is selected. Members are selected randomly which means that every person on the list has as much chance of being selected as another.
Another method of list sampling is making use of alphabetical lists. The population is arranged in alphabetical order. It starts with ‘A’ and for random sampling every nth name is chosen until needed sample is attained e.g. if it is planned to have a 10% sample from the total list, then every 10th name is taken for inclusion in the sample.
Block or Area Sampling In this method, a random sample of areas in which people live is chosen instead of the random sample of the individuals themselves. In this manner, people are grouped together at one place, so that an interviewee can carry out several interviews at one place with very little interval between interviews.
Stratified Sampling In this method, the population is categorized into different classes and a sample is drawn from these classes. With this method, it is possible to get definite proportion of certain characteristics in the sample.
Quota Sampling It is a modification of stratified sampling where it is tried to include some of every known kind of individual of the population in the sample.
Purposive/ Judgment Sampling In this kind of sampling, samples are selected on the basis of the judgment of selector and are unlike the above methods in which everyone in the population has an equal chance of being selected. In this method the sampler handpicks each individual for inclusion in the sample, making up what is intended to be a sample representative of the population from which it is chosen.
Participants