Graduation season for New England college students doesn’t roll around until May. But for New England entrepreneurs, it seems to arrive in November. This month, a trio of so-called accelerator programs — designed to help entrepreneurs transform concepts into companies — held their equivalent of diploma ceremonies, typically dubbed “Demo Days.” That’s when graduating entrepreneurs get the chance to deliver a quick pitch for their ideas to an audience of prospective investors.

The three programs are pretty similar, offering entrepreneurs a place to work for about three months and connecting them with experienced mentors. They supply a small amount of seed money — anywhere from $12,000 to $50,000 — in exchange for a single-digit percentage of ownership in each company. And since they only accept about a dozen companies in each class, they can be tougher to get into than an Ivy League university.