Question

Identify each sample as biased or unbiased. Explain your reasoning.

A clothing chain gives its customers a card they can mail back that asks them questions about the customer’s favorite brand of jeans.

Short answer

The sample is biased.

Step-by-step solution

Step 1. State the concept for sample and population.

A sample is a specific group that you will collect data from. The size of the sample is always less than the total size of the population.

A population is an entire group that you want to draw conclusions about.

a population doesn’t always refer to people. It can mean a group containing elements of anything you want to study, such as objects, events, organizations, countries, species, organisms, etc.

Step 2. State the concept for biased and unbiased samples.

A biased sample means the sample is not representative of the population, which means the method for getting the sample is defective.

An unbiased sample means the sample is representative of the population.

Step 3. State the answer with an explanation.

Since the clothing chain asks only its own customers, the sample is biased. The favorite brand of most of the customers might be the same clothing chain from where they shop. Hence it is favoring one group over the other and is thus biased.