Advantages of Sampling
Why should we settle on a sample instead of studying the entire population? Sampling has the following advantages over a census (study of the entire population):
1. The population may be too large to be studied in full.
For example, a manufacturer of wrist watches may find it impossible to locate all the buyers and obtain their opinions about the product. Instead, the manufacturer may ask the watch retailers to provide the buyers with a response form so that they can fill in their opinions and mail it to the manufacturer. Every buyer is not likely to respond, but those who do, may be treated as a sample from the population of all buyers.A study of a sample is usually cheaper than a study of the population.
2. Sampling usually provides information quicker than a census so that timely decisions can be taken.
3. Sampling involves less work as compared with a census. Hence, the chances of errors while processing the data are less.
4. In destructive testing sampling is the only available course.
For example, if a manufacturer wants to find out the average life of the pencil cell batteries manufactured by his plant, one way to do is to operate each cell until its life is over and record the life duration so that the average life may be computed. However, if every cell is used up this way, the manufacturer will not have any cells for customers. Hence, sampling is the way to determine average cell life in such a case.
5. Testing the entire population may not be possible. For example, if a manufacturer develops a possible remedy for the common cold, all those suffering from this ailment may not be willing to try the remedy. Hence, sampling is the only alternative.