- #1

ckirmser

- 105

- 3

**Summary:**Probability of an event based on a data table

Good morning, all -

I'm working on a question involving obesity based on alcohol and tobacco consumption. The question is based on a table with five variables;

• (age) An age group (10-25, 26-50, 51-75, 76+)

• (alc) An alcohol consumption group in g/day (0-40, 41-80, 80-120, 121+)

• (tob) A tobacco consumption group in g/day (0-10, 11-20, 21-30, 31+)

• (num_case) A number of obese cases (X)

• (num_cont) A number of controls (Y)

The question is, "What is the probability that a subject in the highest alcohol consumption group is obese?"

I figured the answer would be to first select only those rows in the table where alc = "121+". Then, from those, sum the num_case entries and divide that by the sum of num_case entries and the sum of the num_cont entries. In pseudocode;

WHERE alc = "121+"

SUM(num_case) / (SUM(num_case) + SUM(num_cont))

Apparently, this is not the answer, but I can't think of what else it might be.

So, I was hoping someone here might be able to clear this mental roadblock for me.

Thanx in advance!