Compare their syllabi. Ross and PROMYS don't teach what SPARC is teaching, and they don't put these young students into contact with us.
As for effectiveness... what measure of effectiveness did you have in mind?
SPARC and a number of mostly homogeneous math camps are all looking for pre-college students with strong mathematical ability. Since SPARC's syllabus is notably different from that of math camps, it seems like a bad idea to compete with these camps for the top students. But competition is inevitable if SPARC runs at the same time as these camps; below I have found and listed the 2012 start and end dates for the most prominent math camps:
...
Series: How to Purchase AI Risk Reduction
Here is yet another way to purchase AI risk reduction...
Much of the work needed for Friendly AI and improved algorithmic decision theories requires researchers to invent new math. That's why the Singularity Institute's recruiting efforts have been aimed a talent in math and computer science. Specifically, we're looking for young talent in math and compsci, because young talent is (1) more open to considering radical ideas like AI risk, (2) not yet entrenched in careers and status games, and (3) better at inventing new math (due to cognitive decline with age).
So how can the Singularity Institute reach out to young math/compsci talent? Perhaps surprisingly, Harry Potter and the Methods of Rationality is one of the best tools we have for this. It is read by a surprisingly large proportion of people in math and CS departments. Here are some other projects we have in the works:
Here are some things we could be doing if we had sufficient funding: