[davidenarb]

Hi all,

in the bellow example, we would like to know whether the precision has been increased. Therefore, the alternative hypothesis should be : σ² (modified method) > σ ²(std) rather than  σ² (modified method)< σ ²(std) as stated in the solution. Am I correct?  thank you for your confirmation in advance .

[mjc123]

The book is correct. Why do you think it should be otherwise?