Question

You are attempting to determine whether you are taller or shorter than the average student currently enrolled in your university. You have just learned about sampling and have decided to sample students to determine the average height at your university.

Required:

What are some advantages and disadvantages of using sampling to answer this question as opposed to examining the entire population?

Give some other examples of when you would be more likely to use sampling (applied to this particular example) as opposed to examining the entire population.

In what cases might you want to examine the entire population?

Answer 1

Sampling is the procedure in which a sample is selected from an individual or a group of people of certain kind for research purpose. In sampling, the population is divided into a number of parts called sampling units.

Some advantages of sampling are:-

1. Low cost of sampling

If data were to be collected for the entire population, the cost will be quite high. A sample is a small proportion of a population. So, the cost will be lower if data is collected for a sample of population which is a big advantage.

2. Less time consuming in sampling

Use of sampling takes less time also. It consumes less time than census technique. Tabulation, analysis etc., take much less time in the case of a sample than in the case of a population.

4. Accuracy of Data is high

A sample represents the population from which its is drawn. It permits a high degree of accuracy due to a limited area of operations. Moreover, careful execution of field work is possible. Ultimately, the results of sampling studies turn out to be sufficiently accurate.

5. Suitable in limited resources

The resources available within an organization may be limited. The population can be satisfactorily covered through sampling. Where limited resources exist, use of sampling is an appropriate strategy while conducting marketing research.

Some disadvantages of sampling are:-

1. Chances of bias

The serious limitation of the sampling method is that it involves biased selection and thereby leads us to draw erroneous conclusions. Bias arises when the method of selection of sample employed is faulty.

2. Difficulties in selecting a truly representative sample

Difficulties in selecting a truly representative sample produces reliable and accurate results only when they are representative of the whole group. Selecting good samples is difficult.

3. Inadequate knowledge in the subject

Use of sampling method requires adequate subject specific knowledge in sampling technique. Sampling involves statistical analysis and calculation of probable error. When the researcher lacks specialized knowledge in sampling, he may commit serious mistakes. Consequently, the results of the study will be misleading.

Sampling can be used in the above case to determine the average height in the particular university but if the same needs to be identified for all the universities in the city then sampling would be more difficult as the sample size will play an important role in this case. You can opt to study the entire population when the population is well defined(Complete sampling frame) and small. It can eliminate any potential bias occurring through sampling technique, but other than that it is really not justified to consume more resources and time.