A university library ordinarily has a complete shelf inventory done once every year. Because of new shelving rules instituted the previous year, the head librarian believes it may be possible to save money by postponing the inventory. The librarian decides to select at random 800 books from library's collection and have them searched in a pre- liminary manner. If evidence indicates strongly that the true proportion of misshelved or unlocatable books is less than 0.01, then the inventory will be postponed. a. Among the 800 books searched, 20 were misshelved or unlocatable. Test the relevant hypotheses and advise the librarian what to do (use a = 0.05). c. If the true proportion is 0.05, what is the probability that the inventory will be postponed.

A university library ordinarily has a complete shelf inventory done once every year. Because of new shelving rules instituted the previous year, the head librarian believes it may be possible to save money by postponing the inventory. The librarian decides to select at random 800 books from library's collection and have them searched in a pre- liminary manner. If evidence indicates strongly that the true proportion of misshelved or unlocatable books is less than 0.01, then the inventory will be postponed. a. Among the 800 books searched, 20 were misshelved or unlocatable. Test the relevant hypotheses and advise the librarian what to do (use a = 0.05). c. If the true proportion is 0.05, what is the probability that the inventory will be postponed.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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According to the IRS, individuals filing federal income tax returns prior to March 31 received an average refund of $1,078 in 2018 . Consider the population of "last-minute" filers who mail their tax return during the last five days of the income tax period (typically April 10 to April 15). b. For a sample 400 of individuals who filed a tax return between April 10 and 15 , the sample mean refund was $920. Based on prior experience a population standard deviation of a=1,800 may be assumed. What is the p -value (to 4 decimals)? c. Using , can you conclude that the population mean refund for "last minute" filers is less than the population mean refund for early filers? yes or no d. Repeat the preceding hypothesis test using the critical value approach. Using a=0.05 what is the critical value for the test statistic (to 3 decimals)? Enter negative value as negative number. State the rejection rule: Reject if is the critical value. choices: greater than or equal to, greater…
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