How to choose between job offers using science

Suppose you get a phone call one evening about a great job offer from the CEO of your dream company. Just as you finish the conversation with a promise to respond with an answer, another call comes in.

It's your former mentor. He'd like you to join the executive team of his partnership: there you'd name your position, have a great salary and choose your perks. Again, promising to get back to him promptly, you hang up.