See: Financial Analyst, Hedge Fund Manager
If you work in the investment section of a mutual fund, that's pretty much what you'll do all day for starters. If you're too lazy to click, the quick summary is that you will meet with company management, go to conferences and listen to their propogand... er, information/ presentations, and then you'll make financial models which estimate future earnings. Usually based on those estimates, you'll make investments to capture growth in stock prices. Your goal is to be the kind of fortune-teller who can make someone else a fortune.
Note that we only say "growth" here - mutual funds, unlike hedge funds, can't short stocks (make bets that they will go down). Mutual funds can only sell stocks and bonds when they think they are headed south. And mutual funds can't use options either. They are "vanilla" - they can only buy and sell and that's it. And they taste delicious with hot fudge sauce and a maraschino cherry.

We gained weight just looking at this picture.
Mutual funds usually have 3 divisions in the investment area - financial analysts who report in to sell ideas to portfolio managers; portfolio managers who make the buy and sell decisions; and an economics department which opines on - what else? - the economy.
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