Question

Unit 6    [Hypothesis Testing/Decision Making]       

For all Hypothesis\Decision Making Problems, please do the following:

            1.         Answer: Is the data discrete or continuous?

            2.        List the assumptions.

3.        State the null and alternate hypothesis.

            4          Write down the proper test statistic, Show all calculations, i.e. impute the numbers.                       .               Set up Decision rules. Show the critical value.    Reject or Fail to reject.  

            5.         State your conclusions.  

6.2.1

A sample of 25 freshman nursing students made a mean score of 77 on a test designed

to measure attitude toward the dying patient. The sample standard deviation was 10. Do

these data provide sufficient evidence to indicate, at the 0.05 level of significance, that the

population mean is different than 80? Assume that the data follow an approximate

normal distribution.    

                      

Answer 1

Sol:

data :continuous

2.        List the assumptions.

sample is simple random sample

follows normal distribution

3.        State the null and alternate hypothesis.

Ho:

Ha:

4          Write down the proper test statistic,

t=xbar-mu/s/sqrt(n)

=(77-80)/(10/sqrt(25))

=-3/10/5

t=-1.5

Decision rule:

If t stat>t crit ,reject null hypothesis.

if t stat<t crit ,fail to reject null hypothesis.

To get critical t value

df=n-1=25-1=24

alpha=0.05

alpha/2=0.05/2=0.025

Tcritical==T.INV.2T(0.05;24)=​​​​​​​2.063898562

t stat is in the acceptance region.

Accept Ho.

    5.         State your conclusions.  

data do not provide sufficient evidence to indicate  that the population mean is different than 80