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 other dementias. Discuss it by number of cigarettes per day.

People not smoking zero cigarettes is the largest of other demantias

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

Other and different dementias show smoking more than 20 cigs a day

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

Some relationships but in my opinion no because the none smoking bx has the biggest group in each column. The 20 cigs a day column is related

Q4 Creat correlation plot for ‘RailTrail’.

Q5 List all four variables that have negative correlation with the number of trail users (volume).

The four variables are fall(-.25), spring(-.04),cloudcover(-.37), precip(-.23)

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

Fall for trail users since all variables that relate with fall are negative with a volume of (-.25)

Q7 The correlation coefficient between hightemp and cloudcover is quite small. Would you be sure that the two variables are not related at all? .

Yes, correlation is -0.01 so the data hightemp and cloud cover have the littlest correlation.

Q7.a Continued from Q7. 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.

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.