Understanding the concepts and skills 1 Why is sampling ofte

Understanding the concepts and skills

1. Why is sampling often preferable to conducting a census for the purpose of obtaining information about a population?

2. Why should you generally expect some error when estimating a parameter (e.g., a population mean) by a statistic (e.g., a sample mean)? What is this kind of error called?

Solution

1. Complete enumeration of objects is not always possible. Even if it is possible some objects may be lost or destroyed at the time of enumeration. Hence sampling is always preferable to conduct census for the purpose of obtaining information about population.

2. There will always be some error in estimating the population parameter based on a sample because of the methods adopted to obtain a sample. These errors are generally known as sampling errors