Chapter 9, Problem 9.20LB

Chapter 09, Section 9.2, Problem 014a Find the p-value for the following hypothesis test. Ho: µ = 23, H1: u+ 23, n = 81, I= 21.75, o = 6.3 Round your answer to four decimal places. the tolerance is +/-2% powered by MapleNet tudy I Privacy Policy 2000-2020 John Wiley & Sons, Inc. All Rights Reserved. A Division of John Wiley & Sons, MacBook AH

A software developer wants to test if a new mobile phone app they have designed is better than a similar existing app. In particular they wish to test the hypotheses Ho: UN HO and H₁ HN > Ho where UN is the population mean of a satisfaction rating for users of the new app and po is the population mean satisfaction rating for users of the existing app. (The satisfaction rating is scaled so that '0' corresponds to 'worst app ever' and '100' corresponds to 'best app ever'.) The software developer gathers satisfaction ratings from 14 users of the new app and 18 users of the existing app. Using the procedure for a two-sample t-test, the test statistic turns out to be 1.35. What is the value of the critical value at the 5% significance level that this test statistic should be compared with? (Give your answer to three decimal places.) Answer:

4. An herbal extract claimed to raise blood hemoglobin (Hb) level in anemic patients more than a placebo was tested as follows. Test 1. Two different samples (1 and 2, 10 subjects each) were obtained from the population, Sample 1 was given placebo and sample 2 was given the extract and the means of the samples were statistically compared based on X1 bar minus X2 bar. Test 2. 10 anemic subjects were gives capsules containing lactose for 1 month and their mean glucose level (BGL). The extract was given to the same subjects and Hb was measured again for them. Differences between readings were obtained as placebo-herbal. If the question of interest was does the exact result in significant increase of Hb. The null and alternative hypothesis are stated as HO μ ≥ 0, vs HA μ 0 for Test 1. HO: ud s 0, vs HA: ud > 0 for Test 2 HO: μd ≤ 0, vs HA: µd> 0 for Test 1. HO: μ1- 2 ≤ 0, vs HA: p1-u2 > 0 for Test 2

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Chapter 09, Section 9.2, Problem 014b Find the p-value for the following hypothesis test. Ho: u = 20, H:< 20, n = 64, = 18.00, o = 6.4 Round your answer to four decimal places. the tolerance is +/-2% powered by MapleNet dy Privacy Policy I 2000-2020 John Wiley & Sons, Inc, All Rights Reserved. A Division of John Wiley & Sons I MacBook Air

QUESTION 6 The dividing point between the region where the null hypothesis is rejected and the region where it is not rejected is known as the Critical Value. O True O False

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QUESTION 2 You have been hired by “Indo,” the new Indonesian automobile manufacturer to build a model of U.S. car prices in order to help the company undercut U.S. prices. Allowing Friedmaniac zeal to overwhelm any patriotic urges, you build the following model of the price of 35 different American-made 2016 U.S. sedans (standard errors in parentheses): Model A: P₁ = 9.0+ 0.28W; + 1.2T; + 5.8C, + 0.19L₁ (0.07) (0.4) (2.9) (0.20) R² = .92 where: Pi = the list price of the ith car (thousands of dollars) Wi= the weight of the ith car (hundreds of pounds) Ti = a dummy equal to 1 if the ith car has an automatic transmission, 0 otherwise Ci= a dummy equal to 1 if the ith car has cruise control, 0 otherwise Li = the size of the engine of the ith car (in liters) a. Your firm's pricing expert hypothesizes positive signs for all the slope coefficients in Model A. Test her expectations at the 5-percent level. b. What econometric problems appear to exist in Model A? In particular, does the size of…

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