Question

Reported versus Measured. In a survey of 1046 adults conducted by Bradley Corporation, subjects were asked how often they wash their hands when using a public restroom, and 70% of the respondents said “always.”

a. Identify the sample and the population.

b. Why would better results be obtained by observing hand washing instead of asking about it?

Short answer

1. The population comprises people who are adults and use public restrooms and the sample includes 1046 such adults.

2. Observation provides unbiased responses.

Step-by-step solution

Given information

Out of 1046 sampled adults, 70% responded that they always wash their hands after using the public restroom.

Define the sample and population of the study

1. A population is formed of all the items in the data set that are required to be studied. A conclusion is stated for all of these items.
2. A portion of such a population taken for responses is regarded as a sample.

Identify sample and population

In this case, the population consists of all the adults who use public restrooms. They have been targeted for the study.

The sample is a portion of this population that responded to the question, which includes 1046 adults.

Thus,

• Population: All adults who use a public washroom.
• Sample: 1046 adults who responded to the survey.

Explain why the responses gathered through observation are better than asking

1. When responses are gathered from observation, the samples have a higher chance of being unbiased. On the other hand, when responses are obtained on asking a question, there are higher chances that the respondents can lie or give misleading answers that can change the reliability of the results.

Thus, responses gathered by observing adults for handwashing will provide better and more reliable results than asking about it.