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Unformatted text preview: April 16 th Section 7.5 Twosample tests Pooledvariance ttest Pivotal Quantity method Likelihood Ratio test Comparing two population means Example. There are 2 populations. The first population is about men and the second is about women. Paired sample approach Population 1 [Sample 1] Population 2 [Sample 2] Paired difference Pair 1 150 140 10 Pair 2 137 16730 Pair 3 172 155 17 … … … … There can be three cases. : : 0( ) : : M W d M W a M W a d H H H H μ μ μ μ μ μ μ μ = = = ⇔ ≠ ≠ : : 0( ) : : M W d M W a M W a d H H H H μ μ μ μ μ μ μ μ = = = ⇔ f f : : 0( ) : : M W d M W a M W a d H H H H μ μ μ μ μ μ μ μ = = = ⇔ p p Data for d μ is “paired difference” in the above example. The confidence Interval for d μ ⇔ the confidence interval for ( ) M W μ μ 1 “unpaired data” [Independent Samples] Population 1 (Men) [Sample 1] Population 2 (Women) [Sample 2] 1 X 1 Y 2 X 2 Y … … 1 n X 2 n Y Assumptions for pooledvariance ttest for Independent Samples 1. Both populations are normal...
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This note was uploaded on 11/14/2010 for the course AMS 312 taught by Professor Zhu,w during the Spring '08 term at SUNY Stony Brook.
 Spring '08
 Zhu,W

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