Question

Discuss the importance of sampling, and articulate how sampling is related to parameter estimation. Provide practical examples that support your arguments (e.g. examples of how appropriate sampling can provide better parameter estimates for your population you are studying).

Answer 1

(a)

It is often impractical and sometimes undesirable to study entire population. So, sampling is adopted. The purpose of sampling is to obtain representative samples to avoid bias.

(b)

From the sample statistic, through statistical means we can predict the corresponding population parameter. As the sample size = n becomes large, the prediction becomes more accurate.

(c) For example, suppose we want to predict the avrage height of all the students of the college containing 1000 students. In case we are able to get the height of each of the 1000 students and calculate the average, it is the population parameter. But since it is difficult to cover all 1000 students, we take a sample of 50 students and find the average.The average of these 50 students is the statistic.Then we can predict the average height of all 1000 students through statistical methods. In order to get better estimates for population parmeter, we must increase the sample size and make the sampling method unbiased.