Question

use SPSS to calculate the 90%, 95% and 99% confidence intervals for the mean of the variable weight. Interpret the three confidence intervals in terms of whether there is a significant difference between the mean of the sample and a hypothesized mean of 150.

Answer 1

Sample data missing.

For the value needed, find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability of the outliers on each of both ends (.05, .025, .005) and the Z score.

90% = mean ± 1.645 SEm

95% = mean ± 1.96 SEm

99% = mean ± 2.575 SEm

SEm = SD/√n