Comments on Kaufmann

Scientists have made new discoveries about a strange low-level disease. The disease is highly correlated with a particularly gene. 25% of the population has this gene. 90% of those with the gene develop the disease. Among the 75% majority, on the other hand, only 10% develop the disease. There is also a mysterious skin rash which can only occur in people who have the disease. Among the people who have the gene and develop the disease, 90% show the rash. Among the people without the gene that develop the disease, only 10% show the rash. Question Quick – how likely is it that if Peter has the disease, he shows the rash? Question Peter does not have the disease, fortunately. How likely is it that if he had had the disease, he would have shown the rash?