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 none smoking group is the largest group that has Alzheimers.

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

Becaise dementias smoke more than 20 cigarettes a day they have more cases than expected given independence.

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

No because people who have alzheimers are shown to smoke the least.

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)?

Hightemp has the most positive correlation with number of trail users.

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

Hightemp and average seem to be the most popular trail at .92.

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. There is not a relationship because the data is scattered all over the plot.

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.