Question

2. A company is said to be out of compliance i more an 7% of all invoces container ons and it is said to be serious out of ompli n ce more than 며 fi nvoicescontainerrors. uppose an auditorr and mi selects a sample of 640 invoices and finds that 80 contained errors a) Construct a 95% confidence interval for this company's error rate. b) How should the company be rated if statements about being out of compliance or seriously out of compliance require 5% level of significance? c) What is the probability a company would be rated as seriously out of compliance by this test if 12% of all invoices at that company contain erors? d) What sample size should the auditor use to estimate the error rate to within 3% with 99% confidence i It is assumed that the error rate will be no more than 12%? e) Suppose the 80 erroneous invoices can be treated as a random sample from the population of all erroneous invoices. The error amounts are contained in the file http://www.utdallas.cdul-ammann/stat3355scripts/InvoiccErrLtxt Note: since this file just contains a single set of numeric values, you can use the scan() function in R to read this data. For example, InvErr scan("http:/www.utdallas.edu/-ammann/stat3355scripts/InvoiceErrl.txt") onstruct a 9 % confidence interval or the mean er or amount. soobtain and interpret a quantile-quanta e o ot these invoice e ors compared to e normal distribution.

Answer 1

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o n Dect》ton a ach Conelusson: level

0 4 0.35 o 30 10-1。 FoY be1n9 Compliance owin beated: ん.PL9.04 a z- ax led Fe Resechon Reston Based on Zc-1.64

2-P-P o.a <0,95,仆 仅 :0 nclude ﹀ Conclusion: Ha ; p> Ζ.slali,84c is P-Po llauoa: "Th Fuhd a Yejeche Concude

0n Fox ex Sample 31 ze Cn) e. So, n: (860% (о.ias x 0,8チs)lea3=千96'uu(N)부% St, 14. Sample Stze Sloudd be 26