Learning Materials
Features
Discover
Chapter 9: Q.15 (page 547)
When asked to explain the meaning of the P-value in Exercise 13, a student
says, 鈥淭his means there is only probability 0.01 that the null hypothesis is true.鈥� Explain clearly why the student鈥檚 explanation is wrong.
The student鈥檚 explanation is wrong.
Over 30 million students worldwide already upgrade their learning with 91影视!
All the tools & learning materials you need for study success - in one app.
Get started for free
Ancient air The composition of the earth鈥檚 atmosphere may have changed over time. To try to discover the nature of the atmosphere long ago, we can examine the gas in bubbles inside ancient amber. Amber is tree resin that has hardened and been trapped in rocks. The gas in bubbles within amber should be a sample of the atmosphere at the time the amber was formed. Measurements on specimens of amber from the late Cretaceous era ( million years ago) give these percents of nitrogen:
Explain why we should not carry out a one-sample t test in this setting.
Anemia For the study of Jordanian children in Exercise , the sample mean hemoglobin level was mg/dl and the sample standard deviation was mg/dl.
(a) Calculate the test statistic.
(b) Find the P-value using Table . Then obtain a
more precise P-value from your calculator.
Heat through the glass How well materials conduct heat matters when designing houses, for example. Conductivity is measured in terms of watts of heat power transmitted per square meter of surface per degree Celsius of temperature difference on the two sides of the material. In these units, glass has conductivity about . The National Institute of Standards and Technology provides exact data on properties of materials. Here are measurements of the heat conductivity of randomly selected pieces of a particular type of glass:
Is there convincing evidence that the conductivity of this type of glass is greater than ? Carry out a test to help you answer this question.
Packaging CDs (6.2, 5.3) A manufacturer of compact discs (CDs) wants to be sure that their CDs will fit inside the plastic cases they have bought for packaging. Both the CDs and the cases are circular. According to the supplier, the plastic cases vary Normally with mean diameter and a standard deviation . The CD manufacturer decides to produce CDs with mean diameter . Their diameters follow a Normal distribution with .
(a) Let X = the diameter of a randomly selected CD and Y = the diameter of a randomly selected case. Describe the shape, center, and spread of the distribution of the random variable X = Y. What is the importance of this random variable to the CD manufacturer?
(b) Compute the probability that a randomly selected CD will fit inside a randomly selected case.
(c) The production process actually runs in batches of 100 CDs. If each of these CDs is paired with a randomly chosen plastic case, find the probability that all the CDs fit in their cases.
For the study of Jordanian children in Exercise 4, the sample mean hemoglobin level was 11.3 g/dl and the sample standard deviation was 1.6 g/dl. A significance test yields a P-value of 0.0016.
(a) Interpret the P-value in context.
(b) What conclusion would you make if = 0.05? = 0.01? Justify your answer.
What do you think about this solution?
We value your feedback to improve our textbook solutions.
Explanations 
Textbooks 
Flashcards 
91影视 AI 
Notes 
Study Plans 
Study Sets 
Find a degree 
Magazine