Goal of sampling
(go to Outline)
Other than saving time and money, what is the goal of sampling for a survey?
What is necessary to achieve this goal?
We don't really care what the health and nutrition status of the people in the survey sample is. They usually make up a relatively small proportion of the total population. What we really need to know is the health and nutrition status of the entire population which is estimated by measuring indicators and outcomes in a sample of the population.
Remember this point!!
Regardless of the sampling method, if the sample is not representative, it will give you misleading information about the population - so misleading, in fact, that the survey may do more harm than good and add to the confusion rather than enhance clarity.
Whenever you are faced with different ways of doing sampling (should I do it this way or that way?), choose the way that enhances or increases representativeness.
In subsequent pages, three different methods of random sampling will be discussed. All three methods will, if done correctly, result in a representative randomly selected sample. The important point is not the sampling method used, but how correctly the sampling method is used.