STAT 3450 Lecture Notes - Lecture 20: Null Hypothesis, Standard Deviation, Confidence Interval
6 Mar 2017
School
Department
Course
Professor
Document Summary
If x and y be independent normal variables, with. If x has a large sample size nx and y has a large sample size ny then a. Y confidence interval for the difference of the two means is: zyx. Y and the test statistic, (here it is the z-score), for a hypothesis test on the difference of the two means, if the null hypothesis is. )1 rounded down to the nearest integer (note: here we need the assumption that the underlying distributions are normal) The confidence interval and hypothesis test for the difference will be constructed in the same way as for a one sample. Y has an approximately with the computation of as from above: s. If the variances of the two populations can be assumed to be equal, the variances can be pooled" to get a more powerful version of the test.
