Hi, I'm looking at the notes on p16 of chapter 12 and the question asks to test at the 1% level. I am a little confused as to why when comparing the test statistic value (of -2.519) to the lower 1% point of the N(0,1) distribution the value at 0.01 of the tables is picked out instead of half of this (0.005) as is done in previous examples at the 5% level (0.025 and 0.975 are looked at in the tables)? Please can anyone explain to me? Thanks!
It's a one-sided test - so the full 1% is just on one side. the other examples would have been two-sided tests and so it would have been split.
