Analysis 4: exposure groups (dataset v4)

1) Conduct descriptive analyses of all new variables in the dataset. How are the data distributed? What measures of central tendency are appropriate for each?

2) Identify at least five variables that could be used to create exposure groups. Use a graphical or descriptive analysis to crudely evaluate the amount of within- and between-group variability for each of these variables.

3) Of the five (or more) exposure groups you have developed, which do you consider to be the most promising for future use in your exposure analysis, and why?

4) From the assigned reading by Friesen et al, briefly describe in your own words how the authors addressed the issue of assigning exposures to the reference group for their exposure-response analysis given that none of the studied workers was unexposed to wood dust.

5) From the assigned reading by Seixas et al, briefly describe in your own words why the authors suggest that poor correlations between metrics of average exposure and metrics of exposure variability is desirable.