posted by Shawn .
A sample of 64 observations is selected from a normal population. the sample mean is 215 and the standard deviation is 15. conduct the following test of hypothosis using the .3 significance level.
Ho:u > or = 220
H1: u < 220
a) Is this a 1 tailed or 2 tailed test?
b) State the decision rule.
c) Compute the value of the test statistic.
d) What is your decision regarding the H0
e) What is the P value? Interpert
A few hints to get you started:
1. If H1 shows a specific direction, the test is one-tailed. If H1 does not show a specific direction (could be in either tail of the distribution curve), the test is two-tailed.
2. Use a one-sample z-test formula to determine the test statistic.
3. The p-value is the actual level of the test statistic which can be determined using a z-table.
4. Determine the critical or cutoff value to reject Ho using a z-table. If the test statistic exceeds the critical value from the table, reject Ho. If the test statistic does not exceed the critical value from the table, do not reject Ho.
I hope this will help.