EatWell Inc., a large fast-food chain company of Canada, wantsto test two versions of a new product before launching its fullproduction. They select a random sample of individuals among theirregular clients and ask them to participate in an experiment torate the product according to an assessment grid worth 20 points.The 15 individuals who accepted to participate had to come to aspecific company location on two occasions during a given week totest the two versions of the product. It was a randomizedexperiment in which the version assigned to participants duringtheir first visit was selected at random and participants did notknow which version they were rating.

Individual   Version A   Version B
1   17   16
2   17   18
3   20   17
4   11   15
5   15   12
6   16   15
7   15   14
8   16   13
9   12   12
10   16   13
11   19   18
12   14   14
13   17   15
14   18   16
15   18   17

a) Comment on the distribution of the ratings for the twoversions of the product and decide which statistical test is themost appropriate for this type of data. Justify your selectionbased on the assumptions and conditions required for the mostappropriate test selected.

b) Regardless of your answer in a) above, perform a relevantparametric test using a 10% significance level to determine ifthere is a difference between the two versions of the product. Makesure you show your Minitab or other software output along with aninterpretation of the results (manual calculations are not requiredhere).

c) Now, perform a Wilcoxon signed rank test to verify if thereis a significant difference at the 10% level between the twoversions of the product based on these ratings. Show your manualcalculations including the T+ and T- statistics and conclude basedon the critical value approach.

d) Use Minitab or other software to perform the test in c) aboveand comment on the computed Pvalue and your conclusion in c). e)Compare your results from the parametric and non-parametric testsabove and state what the final conclusion regarding the twoversions of the product should be.