Statistics

Eleven employees were put under the care of the company nurse because of high cholesterol readings. The nurse lectured them on the dangers of this condition and put them on a new diet. Shown are the cholesterol readings of the 11 employees both before the new diet and one month after use of the diet began. At 5% level of significance, test the claim that the new diet is effective in lowering cholesterol. Assume differences in cholesterol readings are normally distributed in the population.

 

Employee             Before                       After

1                             255                            197

2                             230                             225

3                             290                             215

4                             242                             215

5                             300                             240

6                              250                            235

7                             215                             190

8                              230                             240

9                              225                             200

10                            219                             203

11                            236                              223 

 

 

EXPECTATIONS
– Draw graphs and charts when appropriate and necessary to demonstrate your reasoning! Label all graphs and charts!
– Display formulas. Write complete sentences to summarize your conclusions.
– If use any table values, clearly state which tables you used (e.g. Table A-2, etc.).
-Attach excel output when appropriate or necessary (e.g. a scatterplot, etc.)

HYPOTHESIS TESTING QUESTIONS
Your work for all statistical hypothesis testing questions should include the following:
1. Established Ho and Ha.
2. Summary statistics (either computed or given in the problem)
3. The name of the test (e.g. 2sampleTtest or T-test about correlation, etc.)
4. A formula to compute a test statistic (e.g. 1Prop-Z test statistic, etc.)
5. A p-value of the test and/or a critical value from a statistical table.
6. Clearly state the decision rule you use the reach a conclusion. (You may have to sketch a graph to show rejection regions.) Do you “Reject Ho” or do you “Fail to Reject Ho”?
7. State your conclusion in plain language. Use complete sentences.