Question

A random sample of 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. Data were observed on the cholesterol readings of the employees both before the new diet and one month after use of the diet began. We'd like to know if there is enough evidence that the mean cholesterol reading for all employees would be lower one month into this new diet.

a) Find the AD (Anderson-Darling) using Minitab. (round to 3 decimal places)

b) Find the degrees of freedom and the p-value for the test, using Minitab. (round to 3 decimal places)

Chol(Before)	Chol(After)
213	206
178	132
290	301
249	249
222	198
207	224
256	225
301	295
192	192
224	229

Answer 1

a) H0: The data follow normal distribution

H1: The data does not follow normal distribution

Let the los alpha = 5%

From the given data

Chol (Before)	Chol (After)	Difference
213	206	7
178	132	46
290	301	-11
249	249	0
222	198	24
207	224	-17
256	225	31
301	295	6
192	198	-6
224	229	-5

Test Statistic AD = 0.363

b) P-value =0.365

Here P-value > alpha 0.05 so we accept H₀

Thus we conclude that the data follow normal distribution