Using Technology. In Exercises 5–8, identify the indicated values or interpret the given display. Use the normal distribution as an approximation to the binomial distribution, as described in Part 1 of this section. Use\(\alpha \)= 0.05 significance level and answer the following:

a. Is the test two-tailed, left-tailed, or right-tailed?

b. What is the test statistic?

c. What is the P-value?

d. What is the null hypothesis, and what do you conclude about it?

e. What is the final conclusion?

Self-Driving Vehicles In a TE Connectivity survey of 1000 adults, 29% said that they would feel comfortable in a self-driving vehicle. The accompanying StatCrunch display results from testing the claim that more than 1/4 of adults feel comfortable in a self-driving vehicle.

Short Answer

Expert verified

a.The test is right-tailed.

b.The value of the test statistic (z-score) is equal to 2.9212.

c.The p-value is equal to 0.0017.

d. The null hypothesis is that the proportion of adults who would feel comfortable in a self-driving vehicle is equal to 25% or 0.25.The null hypothesis is rejected.

e. There is enough evidence to conclude that the proportion of adults who would feel comfortable in a self-driving vehicle is greater than 0.25.

Step by step solution

01

Given information

It is given that out of 1000 adults, 29% of them would feel comfortable in a self-driving vehicle.

02

Tail of the test

a.

According to the given claim, the proportion of adults who would feel comfortable in a self-driving vehicle is more than\[\frac{1}{4}\]or 0.25.

The null hypothesis is represented as follows:

\({H_0}:p = 0.25\)

The alternative hypothesis is represented as follows:

\({H_1}:p > 0.25\)

Since there is a greater than sign in the given claim, the test is right-tailed.

03

Test statistic

b.

The test statistic to test the given claim is the z-score.

Here, the value of the test statistic (z-score) is equal to 2.9212.

04

P-Value

c.

The p-value corresponding to the z-score of 2.9212 is given to be equal to 0.0017.

05

Null hypothesis and its conclusion

d.

The null hypothesis for this test is as follows:

Null hypothesis: The proportion of adults who would feel comfortable in a self-driving vehicle is equal to 25%.

Symbolically,\({H_0}:p = 0.25\)where

p is the proportion of adults who would feel comfortable in a self-driving vehicle.

Here, the p-value equal to 0.0017 is less than the significance level of 0.05. Thus, the null hypothesis is rejected.

06

Conclusion of the test

e.

There is enough evidence to conclude that the proportion of adults who would feel comfortable in a self-driving vehicle is more than 25%.

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Most popular questions from this chapter

Testing Hypotheses. In Exercises 13–24, assume that a simple random sample has been selected and test the given claim. Unless specified by your instructor, use either the P-value method or the critical value method for testing hypotheses. Identify the null and alternative hypotheses, test statistic, P-value (or range of P-values), or critical value(s), and state the final conclusion that addresses the original claim.

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Testing Hypotheses. In Exercises 13–24, assume that a simple random sample has been selected and test the given claim. Unless specified by your instructor, use either the P-value method or the critical value method for testing hypotheses. Identify the null and alternative hypotheses, test statistic, P-value (or range of P-values), or critical value(s), and state the final conclusion that addresses the original claim.

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P-Values. In Exercises 17–20, do the following:

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b. Find the P-value. (See Figure 8-3 on page 364.)

c. Using a significance level of α = 0.05, should we reject H0or should we fail to reject H0?

The test statistic of z = -2.50 is obtained when testing the claim that p<0.75

P-Values. In Exercises 17–20, do the following:

a. Identify the hypothesis test as being two-tailed, left-tailed, or right-tailed.

b. Find the P-value. (See Figure 8-3 on page 364.)

c. Using a significance level of α= 0.05, should we reject or should we fail to reject ?

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Testing Claims About Proportions. In Exercises 9–32, test the given claim. Identify the null hypothesis, alternative hypothesis, test statistic, P-value, or critical value(s), then state the conclusion about the null hypothesis, as well as the final conclusion that addresses the original claim. Use the P-value method unless your instructor specifies otherwise. Use the normal distribution as an approximation to the binomial distribution, as described in Part 1 of this section.

Touch Therapy Repeat the preceding exercise using a 0.01 significance level. Does the conclusion change?

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