Unformatted text preview: > 3.16) = 2(.003) = .006. At the 5% level of significance, we reject the null
hypothesis and conclude that the data provides sufficient evidence to conclude that there is a difference in the mean shear
strength between the two steel types.
26. Because the standard deviations are so similar, the degrees of freedom for the two test types (pooled versus unpooled) are
hardly any different. The alternate hypothesis of Ha: 1  2 > 0 is onesided, and the SAS output shows a positive test
statistic, so the pvalues reported by SAS are twice the actual size. The pvalue is therefore .0004. Since this is much
smaller than the significance level of .01, we reject the null hypothesis. The data indicates that the mean potential drop for
type alloy connections (type 1) exceeds the mean for EC connections (type 2). Since the null hypothesis was rejected, the
only possible error that could have been committed was a Type I error. Beverage
29. The data is summarized in the table. The following analysis assumes that the
Strawberry
compression strength of both beverages is normally distributed. The hypothesis
Cola
that cola compressive strength is greater gives t...
View
Full
Document
This note was uploaded on 09/17/2012 for the course STAT 312 taught by Professor Chung during the Spring '04 term at University of Wisconsin.
 Spring '04
 Chung
 Standard Error

Click to edit the document details