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Course Documents
Chapter 1 - Intro
Chapter 2 - Methods for Describing Sets of Data
Chapter 3 - Probability
Chapter 4 - Discrete Random Variables
Chapter 5 - Normal Random Variables
Chapter 6 - Sampling Distributions
Chapter 7 - Confidence Intervals
Chapter 8 - Tests of Hypothesis: One Sample
Chapter 9 - Confidence Intervals and Hypothesis Tests: Two Samples
Sample Exam I: Chapters 1 & 2
Sample Exam II: Chapters 3 & 4
Sample Exam III: Chapters 5 & 6
Sample Exam IV: Chapters 7 & 8
Is it safe to assume that in HW: 9.5, where The Goverment's mean is 35.50 and the Private is 54.6, that the final interval is going to be negative. (This could be in any situation) Per say if Goverment mean is 54.6 and 35.50 that the final interval is positive ?
Posted to STATS 2 on Thursday, October 17, 2013 Replies: 2
Hi Andrea,
No, you can't assume the interval will be all positive or all negative just by looking at the sample means. The first reason is that it depends on how you set up the subtraction in the interval. The second reason is that there may not be a significant difference between the two means in question. In that case, you will get an interval that is both negative and positive.
There is no way to avoid actually calculating the confidence interval to determine if there is a significant difference between the means.
Hope that answers your question,
Professor McGuckian