9.5 Tests Concerning Two MeansHo: Hi = P2 (can also be written as µi - H2 = 0) OR HI < Hz OR HIZ 2Ha: Hi < µ2 OR µi > µ2 OR µi # µ2Determining the Test StatisticCaseTest Statistic1For o1 and o2 known; Independent SamplesX1 – x2z =+n22For ơ1 and o2 unknown AND ni, n2 2 30; Independent SamplesX1 — х2z =Sĩ+n2For ơ1 = 02 unknown (assumed equal) AND ni, n2 < 30; Independent Samplestaken from Normal Populations3(m-1)s +(n2 -1)s?х1 — х2t =where Sp11+nị +n2 - 2Sp.with v = ni + n2 – 2 degrees of freedom S is the pooled sample variance.4For paired observations; RELATED Samples with Paired Differences coming froma Normal Populationdt =SdInwith v = n-1 degrees of freedom Suppose that hemoglobin levels in white males over age 11 are normally distributed withvariance 1.462 and that those for white males age 11 or under are normally distributed withvariance 0.867. Independent random samples of 10 older and 20 younger white males areselected and produce sample means of 13.47 g per 100 ml and 12.64 g per 100 ml,respectively. Do the data indicate that older white males have higher hemoglobin levelsthan younger white males? Use a 0.01 level of significance.

Answered: Suppose that hemoglobin levels in white…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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