BCB744 Task G
Assessment Sheet
8. Analysis of Variance (ANOVA)
Refer to the lecture material to see the questions in context (see Task G.x: Do it now!).
Questions 1
Why should we not just apply t-tests once per each of the pairs of comparisons we want to make? (/3)
Question 2
- What does the outcome say about the chicken masses? Which ones are different from each other? (/2)
- Devise a graphical display of this outcome. (/4)
Question 3
Look at the help file for the TukeyHSD()
function to better understand what the output means.
- How does one interpret the results? What does this tell us about the effect that that different diets has on the chicken weights at Day 21? (/3)
- Figure out a way to plot the Tukey HSD outcomes in ggplot. (/10)
- Why does the ANOVA return a significant result, but the Tukey test shows that not all of the groups are significantly different from one another? (/3)
Question 4
- How is time having an effect? (/3)
- What hypotheses can we construct around time? (/2)
Question 5
- What do you conclude from the above series of ANOVAs? (/3)
- What problem is associated with running multiple tests in the way that we have done here? (/2)
Question 6
- Write out the hypotheses for this ANOVA. (/2)
- What do you conclude from the above ANOVA? (/3)
Question 7
- What question are we asking with the above line of code? (/3)
- What is the answer? (/2)
- Why did we wrap
Time
inas.factor()
? (/2)
Question 8
How do these results differ from the previous set? (/3)
Question 9
Yikes! That’s a massive amount of results. What does all of this mean, and why is it so verbose? (/5)
Reuse
Citation
BibTeX citation:
@online{smit,_a._j.,
author = {Smit, A. J.,},
title = {BCB744 {Task} {G}},
url = {http://tangledbank.netlify.app/assessments/BCB744_Task_G.html},
langid = {en}
}
For attribution, please cite this work as:
Smit, A. J. BCB744 Task G. http://tangledbank.netlify.app/assessments/BCB744_Task_G.html.