While the number of detected exoplanets is still low, is there a model that, considering the number and duration of made observations, and the fact that (non)detections depend on orbital plane alignment and timing, can answer questions like
what is the typical number of exoplanets for a star?
what percentage of extrasolar systems can be expected to have at least one exoplanet?
how many (Jupiter, Earth)-like planets do we expect in each solar system?
which types of stars tend to have which types of planets?