The following data are from Mattison et al who carried out a

The following data are from Mattison et al., who carried out an experiement with rhesus monkeys to test whether a reduction in food intake extends life span (as measured in years). Does food intake affect lifespan? Does this depend on the gender of the individual? In a study of 19 males and 15 female adult monkeys fed a normal diet, or a similar diet reduced by 30%, the following lifespans were found:

Address the questions posed in this study, with appropriate analysis. Check assumptions, use five step approach to hypothesis testing and give an interpretation of the results.

A LAYULLEVY OU70, unle IOllowing IIIEspans in yearSJ Were TOU Females on the reduced diet: 16.5, 18.9, 22.6, 27.8, 30.2, 30.7, 35.9 Females on the normal diet: 23.7, 24.5, 24.7, 26.1, 28.1, 33.4, 33.7, 35.2 Males on the reduced diet: 23.7, 28.1, 298, 31.1, 36.3, 37.7, 39.9,39.9, 40.2, 402 Males on the normal diet: 24.9, 25.2, 29.6, 33.2, 34.1, 35.4, 38.1, 38.8, 40.7

Solution

Mean of female reduced diet = (16.5+18.9+22.6+27.8+30.2+30.7+35.9)/7 = 26.085

Mean of female normal diet = (23.7+24.5+24.7+26.1+28.1+33.4+33.7+35.2)/8 = 28.675

Mean of male reduced diet = (23.7+28.1+29.8+31.1+36.3+37.7+39.9+40.2+40.2)/9 = 30.7

Mean of male normal diet = (24.9+25.2+29.6+33.2+34.1+35.4+38.1+38.8+40.7)/10 = 30

The males on normal diet have a lesser life span than the males on reduced diet, whereas the female normal diet has a higher life span than the females on reduced diet