>>11897749>Its not that bad of an informal definitionActually it's not bad at all. An informal dumbed down explanation is definitely a great way to teach people. You can either first explain the dumbed down version, show some examples and then the formal one, or explain the formal one, then dumb it down with examples and back to the formal one. It's a great way to teach something new to people. The definition seen on OP's image is probably a cheat sheet or an exercise/example or the professors own notes. If you found this in an actual textbook, then you'd have a reason to worry, but an informal easier to understand definition is definitely better. You don't teach a kid in high school what an integer is using it's formal definition. You probably say something stupid like an integer is a number without numbers after the decimal point. Then you give some examples of integers, and later on, when they understand what an integer is, you give the formal definition, go step by step over each part of the definition and what it means and even dumb down the harder to get parts. That's part of teaching. No one was born knowing what the fuck is a random variable and they sure as hell won't know what the fuck it is if you give them the formal definition, especially if they have never taken statistics before.
