Question

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Microsoft Outlook is believed to be the most widely used e-mail manager. A Microsoft executive claims that Outlook is used by at least 75% of Internet users. A Merill Lynch study involving 300 respondents reported that 72% use Microsoft Outlook. Can you prove that the executive's claim is not valid? What is the relevant point estimate? 0.72 What is the value of the test statistic? -1.2000 This test statistic has: A standard normal distribution At distribution with 299 degrees of freedom A normal distribution At distribution with 298 degrees of freedom At distribution with 300 degrees of freedom 0.8849 What is the p-value for this test? Allowing for a 5% chance of a Type I error, what is your conclusion for this test? O Reject the null hypothesis and conclude that there is insufficient evidence that the Microsoft's executive claim is not valid. Do not reject the null hypothesis and conclude that the Microsoft executive's claim is not valid. Do not reject the null hypothesis and conclude that there is insufficient evidence that the Microsoft executive's claim is not valid. Reject the null hypothesis and conclude that the Microsoft's executive claim is not valid.

Answer 1

Z-hypothesis test of single Proportionality.

Given that cutleok is b atleat 157. Tnternet Eeys Vsed Sample Size Cn) Sample Propoxtion (P) Releven Point Esti male Test Statistic (E) J PG/n -P =-07S O.25 - Co72-075 Z-Slatictic Abymal distribtion Test statistil has P-alue =O.05 at (で1ーフヌ)』 P o.150J -12 くー

HeaN Null hyothesis (ito) P 0-15 Cone-tailes) 2 Altevnative hyo the sie (H Cordoson Z-critical lue -645 | Zcxitice!] > {Z-statistic } l1-645 11-2) Accept o Aull hyfathesis Donat eect the Null hyPatheSis and Gndude that there is insifficient Evidence tt the claim (s not valid micxosoft Eeccutiv