Question: A study was conducted to investigate the effects of differing doses of insulin on the blood sugar levels of guinea pigs. The guinea pigs were randomly assigned to three treatment groups (A, B, and C). Pre-treatment blood sugar levels were measured and the appropriate insulin treatment was administered according to group assignment. After three hours, the blood sugar levels were remeasured and the percentage decrease in blood sugar was calculated.

Research Question: Is there a difference in the average percentage decrease in blood sugar based on the insulin treatment administered?

i) Do these data provide sufficient evidence to indicate a difference in mean scores among the groups? Test at the 10% level of significance level. Be sure to include the assumptions required to implement this test. State whether you would do a post hoc analysis (but do not have to do if one is indicated).

ii) Test the data set for normality using the appropriate hypotheses.

iii) Test the data set for equality of variance.

iv) Use the Scheffe test to determine which (if any) of the pairs of means differ significantly at the .10 level of significance

Group Blood sugar

1.00 13.60
1.00 17.40
1.00 21.80
1.00 14.70
1.00 16.30
1.00 21.20
2.00 19.20
2.00 23.90
2.00 26.00
2.00 16.40
2.00 19.50
2.00 22.10
3.00 24.20
3.00 20.40
3.00 16.20
3.00 31.20
3.00 28.00
3.00 23.80