Question

Null hypothesis is the hypothesis that the researcher is trying to disprove.It is denoted by H0

Alternative hypothesis is the hypothesis that the researcher is trying to prove. It is reverse of null hypothesis and denoted by Ha

Lets take an case where we need to test the claim which says the mean weight of the student in class of 50 students exceeds 150 pounds

Here, the thing we are trying to prove is mean(u) >150

Thus, as discussed

Null Hypothesis - hypothesis that the researcher is trying to disprove: u <= 150

Alternative Hypothesis - hypothesis that the researcher is trying to prove: u > 150

Once we state the null hypothesis we find test statistic and corresponding p value

If p value <= 0.05 we reject null hypothesis

If p value > 0.05 we fail to reject null hypothesis

where, 0.05 is general level of significance

**Question-What do we need to find the test statistic? How do we find it?

Answer 1

This is the test for population mean for one sample.

So for this test we use either Z Statistic or t statistic .

To calculate this we need the sample size n , sample mean M and standard deviation.

If we know the population standard deviation then we will use Z statistic and it is given by

If we don't know the population standard deviation then we calculate the Sample standard deviation S and then we use t statictic and it is given by

Where is the population mean under the Null Hypothesis. Which is here 150 .