Hasty Generalization.

Is committed when the arguer draws a conclusion about all members of a group from characteristics of a few members. It is a fallacy if there is no reason to think that the example individuals are typical. (Sample might be too small, or the sampling might be systematically biased.)

I think I won't accept the job at Office Depot. My boss would be a woman, and at my last job my boss was a woman, and she was the worst boss I've ever had.

You spend all your time watching football! I've called you over a dozen times in the last few months, and every single time you're watching football! Don't you have a job, or any friends?

Farmer Bob used Stinky Winky fertilizer at three spots in his corn field, and at those three spots the corn plants died. All the other plants in the field lived. Stinky Winky fertilizer is obviously bad for corn plants.