1.    Refer to the data in Table 1. The data are in a .csv file on Blackboard. Enter the data into R and consider the following:

a.    What is the Risk of dying from West Nile Virus when the syndrome was unknown?

b.    What is the Risk of dying from West Nile Virus when the syndrome was WNND?

c.    What is the Relative Risk?

d.    What can you say about the Relative Risk in this example?

 

2.     Again, refer to the data in Table 1.

a.    What is the odds ratio of dying from West Nile Virus when the syndrome was unknown compared to when the syndrome was WNND?

b.    What is the odds ratio of dying from West Nile Virus when the syndrome was WNND compared to when the syndrome was unknown?

c.    Is the Odds ratio significant?

d.    What can you say about the odds of dying from West Nile Virus in this example?

 

3.    R calculated the ratio (for risk and odds) confidence intervals for you. How would you do it by hand? Hint: remember our discussion about the log of the odds and taking the exponent (which is the opposite of a log). Note: calculate away if you would like to illustrate your point or check your work, but I am looking for a few sentences describing the process.

 

Table 1: West Nile Virus

 

Death

Syndrome

Yes

No

Unknown

8

83

WNND*

15

194

* West Nile Virus Neuroinvasive Disease