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Chapter 4: Q 33. (page 229)

Running red lights The sample described in Exercise 31produced a list of 5024licensed drivers. The investigators then chose an SRS of 880 of these drivers to answer questions about their driving habits. One question asked was: 鈥淩ecalling the last ten traffic lights you drove through, how many of them were red when you entered the intersections?鈥� Of the 880 respondents, 171admitted that at least one light had been red. A practical problem with this survey is that people may not give truthful answers. What is the likely direction of the bias: do you think more or fewer than 171 of the 880 respondents really ran a red light? Why?

Short Answer

Expert verified

We expect more than 171 respondents to admit that they ran a red light.

Step by step solution

01

Given information

A sample size of drivers, n=880

A practical problem with this survey is that people may not give truthful answers.

02

Concept

A simple random sample (SRS) of size n is made up of n people chosen from the population with an equal chance of being the sample that is actually chosen.

03

Explanation

There could have been a large number of persons that ran a red light. However, due to societal difficulties, most will not admit to running a red light. As a result, we predict more than 171 people to admit to running a red light.

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