ANOVA of the Fruitfly Data

In this activity, you will be performing an ANOVA on the fruitfly data to determine whether the longevity of males is related to their reproductive cycle. Studies have shown that the longevity (life span) of female fruitflies decreases with an increase in reproduction, and this leads to the question related to males.

The design of the study placed male fruitflies in the following groups:
1) males living alone,
2) males living with one interested female,
3) males living with eight interested females,
4) males living with one uninterested female, and
5) males living with eight uninterested females.


The hypothesis was that the males living alone and with the uninterested females would live longer than the males living with the interested females. Since there are more than two group means, an ANOVA is used to determine if there is a significant difference between the group means. 

Using Excel, perform an ANOVA to determine if there is a significant difference between the five groups.

If there is a significant difference, you will need to determine the means that are significantly different by doing a post hoc Tukey Test.

This data exists in Excel Data format.

1. What is the p value?
2.
With alpha equals 0.05, what does the p value tell you, specifically, about this data?
3. What are the F-stat and F-critical values?

4. Is there a statistically significant difference somewhere between the groups?
5. How do the F-stat and F-critical values give you the answer to question four?
6. If there is a statistically significant difference somewhere between the groups, use the Tukey Test to identify between which groups, include your Tukey Table in your assignment, and list those pairs of groups.
7. Does reproductive activity (or the number and condition of the flies with which the males were living) affect the longevity of male fruitflies?

Oh, if you are wondering how one determines "interest" in fruitflies, here is the scoop! Newly inseminated females will not usually mate again for at least two days. So the males in the uninterested groups were always living with newly inseminated females!


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