Probability of failure of a campaign This is a simplistic question. It is about the issue of running a campaign in a newspaper. There are two issues here: (i) The chances of failure vs success of a well-planned, well-written, and well-excuted campaign page (in terms of leaving an impact on a reader) is 25 vs 75. (ii) The chances that a page (any page, not necessarily campaign) littered with ads will put off the reader is 90 vs 10. So, what are the chances of a failure if a campaign page is littered with ads? (Ceteris paribus; all other things remaining constant) Thanks. Subir

A crude model would assume independence. There is **success** if (a) the person gets past her general hostility to pages littered with ads (probability $0.10$), **and** (b) responds positively to the political material (probability $0.75)$. So the probability of success is $(0.10)(0.75)=0.075$. Thus the probability of failure is $1-0.075$.

In a real-world situation of this kind, a naive probability calculation of this kind may make little practical sense.