Exercises 9.101-9.106 pertain to P-values for a one-mean t-test. For each exercise, do the following tasks,

a. Use Table IV in Appendix A to estimate the P-value,

b. Based on your estimate in part (a), state at which significance levels the null hypothesis can be rejected, at which significance levels it cannot be rejected, and at which significance levels it is not possible to decide

Right-tailed test,n=20 andt=2.235

Short Answer

Expert verified

Part (a) 0.01<P<0.025

Part (b) We can reject H0at any significance level of 0.025or larger, and can not reject H0at any significance level of 0.01or smaller.

Step by step solution

01

Part (a) Step 1. Given information

The given Right-tailed testn=20,t=2.235

02

Part (a) Step 2. Use Table IV in Appendix A to estimate the P-value 

Because the test is right tailed, the P-value (P)is the area under the t-curve with

df=20-1=19

that lies to the right of observed t value,t0=2.235 ;
i.e.P=P(t>t0), wheret~t19.
In the df=19row of the table-IV, we can see that the two t-values that straddle 2.235in between t0.025=2.093and t0.01=2.593. Therefore the area under the t-curve that lies to the right of t0=2.235is between 0.01and 0.025.
Hence,0.01<P<0.025

03

Part (b) Step 1. Given information

The given Right-tailed testn=20,t=2.235

04

Part (b) Step 2. Based on your estimate in part (a), state at which significance levels the null hypothesis can be rejected, at which significance levels it cannot be rejected, and at which significance levels it is not possible to decide 

We can rejectH0at any significance level of0.025or larger, and can not rejectH0at any significance level of0.01or smaller.
For significance levels between 0.01and 0.025, table-IV is not sufficiently detailed to help us to decide whether to rejectH0

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

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?

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 20

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 with blue eyes is equal to 0.35.

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.

Heights of Supermodels Listed below are the heights (cm) for the simple random sample of female supermodels Lima, Bundchen, Ambrosio, Ebanks, Iman, Rubik, Kurkova, Kerr,Kroes, Swanepoel, Prinsloo, Hosk, Kloss, Robinson, Heatherton, and Refaeli. Use a 0.01 significance level to test the claim that supermodels have heights with a mean that is greater than the mean height of 162 cm for women in the general population. Given that there are only 16 heights represented, can we really conclude that supermodels are taller than the typical woman?

178 177 176 174 175 178 175 178 178 177 180 176 180 178 180 176

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 Body Temperatures The claim is that for 12 am body temperatures, the mean is μ<98.6°F.The sample size is n = 4 and the test statistic is t = -2.503.

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