Mosaic Plot
Kacey Paquette
03/19/2020
In this exercise you will learn to visualize the pairwise relationships between a set of quantitative variables. To this end, you will make your own note of 8.5 Mosaic plots from Data Visualization with R.
Mosaic charts can display the relationship between categorical variables using:
- rectangles whose areas represent the proportion of cases for any given combination of levels, and
- the color of the tiles to indicate the degree relationship among the variables.
The Titanic data set came from https://osf.io/aupb4/.
In the graph below,
- dark blue represents more cases than expected given independence (by chance); and
- dark red represents less cases than expected if independence holds (by chance).
Q1 Are more passengers survived?
No ## Q2 Describe the largest group that didn’t survive. Discuss by class and gender. 3rd class male
Q3 Describe the largest group that did survive. Discuss by class and gender.
1st class female
Q4 Describe one group that has more cases than expected given independence (by chance). Discuss by class and gender.
3rd class male not survived more than we expected ## Q5 Describe one group that has less cases than expected given independence (by chance). Discuss by class and gender. More 3rd class male didnt survive than expected, fewer 3rd class male survived than expected
Q6 Create a mosaic plot for Arthritis in the same way as above.
Hint: The Arthritis data set is from the vcd package. Add an additional argument gp = shading_max in the mosaic function. This is because the residuals are too small to have color. 
Q7 Repeat Q1-Q5.
- Non improvement is the largest group
- Placebo didnt recieve any treatment
- Yes treatment, a lot of improvement 4/5.No treatment, fewer patients showed marked improvements than expected. Treament means a lot of improvement.
Q8 Hide the messages, the code and its results on the webpage.
Hint: Use message, echo and results in the chunk options. Refer to the RMarkdown Reference Guide.