Question

Exercise 15. ANOVA. A researcher wanted to determine the most effective diet for reducing LDL cholesterol, the so-called ”bad” cholesterol, among 3 diets: (1) a saturated-fat diet, (2) the Mediterranean diet, and (3) the NCEP-1 diet. Participants in the study were shown to have the same levels of LDL cholesterol before the study and were randomly assigned to one of the 3 diets. After 28 days, their LDL cholesterol levels were recorded. Assume the samples are independent and that they are taken from populations with equal variances. The data is shown in the table below. Use a one-way ANOVA to test whether there is a difference in at least one of the mean LDL cholesterol levels at

α = 0.05. Reminder: When using tables with degrees of freedom (i.e. d.f.N or d.f.D) if the value is not listed in the table explicitly, use the next lower d.f. value in the table.

Saturated Fat	Mediterranean	NCEP-1
245	56	125
122	78	100
166	101	140
104	158	151
196	145	138
300	118	208
140	145	75
240	211	71
218	131	184
173	125	116
223	160	144
177	130	101
193	83	135
224	243	144
149	150	130

Answer 1

(1) Null and Alternative Hypothesis:

H0:  There is no significance difference in at least one of the mean LDL cholesterol levels

H1:  there is significance difference in at least one of the mean LDL cholesterol levels

i.e.

(3) Test Statistic: From the given data

Thus we conclude that  there is significance difference in at least one of the mean LDL cholesterol levels