ANOVA of the Fruitfly Data

In this activity, you will be performing a single factor ANOVA on the data to determine whether the longevity of male fruitflies 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 any two (or more) group means. 

Using Excel, perform a single factor ANOVA to determine if there is a significant difference between any two of the five groups. Be certain to select "new worksheet ply" for the ANOVA output table.

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. For your assignment, you will turn in a hard copy single page in portrait orientation. Your name and class period will be in a header in the upper right-hand corner. The data will not be included; the page will start in cell A1 with the ANOVA output table. Underneath the table you will answer the questions below in complete sentences. Be sure to spell check and proofread your work. Use "wrap text" or another technique to keep your answers to a single printed page.

1. What is the p value?
2.
With alpha equals .05, what does the p value tell you to do with the Null Hypothesis?
3. What are the F-stat and F-critical values?

4. Is there a statistically significant difference somewhere between the groups?
5. How do you use the F-stat and F-critical values to identify if a statistically significant difference exists between two or more group means?
6. Run a Tukey Test. Write a sentence to identify the Qt value and the Dmin values as the answer to this item.
7. List the pairs of groups between which a statistically significant difference lies.
8. Does the data suggest that reproductive activity (or the number and condition of the flies with which the males were living) affect the longevity of male fruitflies?
9. Include your Tukey Test Difference of Means table at the bottom of your page.

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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