Quiz3

The data set is from a case-control study of smoking and Alzheimer’s disease. The data set has two variables of main interest:

• smoking a factor with four levels “None”, “<10”, “10-20”, and “>20” (cigarettes per day)
• disease a factor with three levels “Alzheimer”, “Other dementias”, and “Other diagnoses”.

Q1 Describe the largest group that has Alzheimer. Discuss it by number of cigarettes per day.

The largest group that has Alzhiemers is none smoking group. As it has the largest width compared to the other groups.

Q2 Describe one group that has more cases than expected given independence (by chance). Discuss it by number of cigarettes per day.

The group that has more cases than expected given independence is the other dementias that smoke 20 or more cigarettes a day. The box is blue indicating more cases than expected.

Q3 Does smoking seem to matter in determining Alzheimer? Discuss your reason using the masaic chart above.

Smoking does not seem to determine Alzheimers because the largest group of people with Alzheimers don’t smoke at all.Therefore no correlation explaining the many gray boxes.

Q4 Create correlation plot for RailTrail.

Hint: The RailTrail data set is from the mosaicData package.

## Q5 What variables have positve correlation with the number of trail users (volume)?

The variables that have positive correrlation with the number of trail users is high temp and average temp. In the table they are both red colored in relation to volume.

Q6 What season seems to be most popular for trail users?

The most popular season for trail users is summer. The variable for summer has a positive relation to volume, whereas fall has a negative relationship.

Q7 The correlation coefficient between hightemp and cloudcover is quite small. Would you be sure that the two variables are not related at all? Create scatter plot. After examing the scatter plot, would you conclude that the two variables are not related at all?

Hint: Discuss your reason by explaining your scatter plot. Based off the mosaic table and the scatterplot, hightemp and cloudcover have little to no linear relationship. The scatterplot displays no linear relationship because the data points are very spread out throughout the graph making it basically impossible to have a linear relationship or relation in general.

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.

Q9 Display the title and your name correctly at the top of the webpage.

Q10 Use the correct slug.