Finding P-values. In Exercises 5–8, either use technology to find the P-value or use Table A-3 to find a range of values for the P-value.

Airport Data Speeds: The claim that for Verizon data speeds at airports, the mean\({\bf{\mu = 14}}{\bf{.00}}\;{\bf{mbps}}\). The sample size is \({\bf{n = 13}}\) and the test statistic is

t =-1.625 .

Short Answer

Expert verified

The p-value lies between 0.10 and 0.20.

Step by step solution

01

Given information

The claim states that the mean of data speeds is\(\mu = 14.00\;{\rm{mbps}}\).

The sample size is\(n = 13\) with the test statistic \(t = - 1.625\).

02

State the hypotheses

As per the claim, the hypotheses are stated as follows.

\(\begin{array}{l}{H_0}:\mu = 14\;({\rm{null}}\;{\rm{hypothesis}})\\{H_1}:\mu \ne 14\;({\rm{alternative}}\;{\rm{hypothesis}}\;{\rm{and}}\;{\rm{original}}\;{\rm{claim}})\end{array}\)

Hence,it is a two-tailed test.

03

Compute the degrees of freedom 

The degrees of freedom for the given set of data are as follows.

\(\begin{array}{c}df = n - 1\\ = 13 - 1\\ = 12\end{array}\)

04

Computing p-value using Table A-3

The test is a two-tailed with 12 degrees of freedom and test statistic value of

-1.625.

In Table A-3, check for the value 1.625 in the row with 12 degrees of freedom to see test statistic. The value 1.625 lies between 1.356 and 1.782.

The corresponding two-tailed area indicates the P-value between 0.10 and 0.20.

Hence, this can be written as\(0.10 < \;P - value < \;0.20\)

Thus, the range of p-value is 0.10 and 0.20.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

In Exercises 13–16, refer to the exercise identified and find the value of the test statistic. (Refer to Table 8-2 on page 362 to select the correct expression for evaluating the test statistic.)

Exercise 6 “Cell Phone”

Type I and Type II Errors. In Exercises 29–32, provide statements that identify the type I error and the type II error that correspond to the given claim. (Although conclusions are usually expressed in verbal form, the answers here can be expressed with statements that include symbolic expressions such as p = 0.1.).

The proportion of people who require no vision correction is less than 0.25.

Critical Values. In Exercises 21–24, refer to the information in the given exercise and do the following.

a. Find the critical value(s).

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

Exercise 18

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.

Is the Diet Practical? When 40 people used the Weight Watchers diet for one year, their mean weight loss was 3.0 lb and the standard deviation was 4.9 lb (based on data from “Comparison of the Atkins, Ornish, Weight Watchers, and Zone Diets for Weight Loss and Heart Disease Reduction,” by Dansinger et al., Journal of the American Medical Association, Vol. 293, No. 1). Use a 0.01 significance level to test the claim that the mean weight loss is greater than 0. Based on these results, does the diet appear to have statistical significance? Does the diet appear to have practical significance?

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.

Store Checkout-Scanner Accuracy In a study of store checkout-scanners, 1234 items were checked for pricing accuracy; 20 checked items were found to be overcharges, and 1214 checked items were not overcharges (based on data from “UPC Scanner Pricing Systems: Are They Accurate?” by Goodstein, Journal of Marketing, Vol. 58). Use a 0.05 significance level to test the claim that with scanners, 1% of sales are overcharges. (Before scanners were used, the overcharge rate was estimated to be about 1%.) Based on these results, do scanners appear to help consumers avoid overcharges?

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free