Based on the information given for each of the following studies, decide whether to reject the null hypothesis. For each, give (a) the Z-score cutoff (or cutoffs) on the comparison distribution at which the null hypothesis should be rejected, (b) the Z score on the comparison distribution for the sample score, and (c) your conclusion. Assume that all populations are normally distributed.

Question

Based on the information given for each of the following studies, decide whether to reject the null hypothesis. For each, give (a) the Z-score cutoff (or cutoffs) on the comparison distribution at which the null hypothesis should be rejected, (b) the Z score on the comparison distribution for the sample score, and (c) your conclusion. Assume that all populations are normally distributed.
 	Population	 	 	 
Study	μ	σ	Sample Score	p	Tails of Test
A	5	1	7	.05	1 (high predicted)
B	5	1	7	.05	2
C	5	1	7	.01	1 (high predicted)
D	5	1	7	.01	2

I would prefer not the answer given but please show me how to do it. I just do not understand.

PsyDAG · Answer

What level of significance are you using? P ≤ .05? P ≤ .01?

Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions related to the Z scores. For a one-tailed test, find Z with .05, but with a two-tailed test, look for Z with .025. If using P ≤ .01, use similar process.

Kathy · Answer

i have the answers, but does not have the answers for the set of problems I was working on. That was one of my questions I was not completly sure of. I copied the problem word for word from the text. I did as much calculations as I knew how...it was then trying to figure out how to get the probability i think. This chapter threw me for a loop.