1. ## Re: Joint PDF problem

Originally Posted by _joey
because it is a property of a joint distribution function. And either way you integrate it should be equal to 1. You are still not sure?
you obviously don't know what you are talking about.

Just to end this quickly...if you want to integrate x then y you can do this...

though I already showed that it integrated to 1 so this is just a waste of time.

2. ## Re: Joint PDF problem

What he is saying is that you can integrate it in either order but the limits of your integration might need to change to reflect that. If you have variables in your integration limits you can't just switch the order without changing things around.

3. ## Re: Joint PDF problem

Originally Posted by Martingale
S

Edit: let me clarify since you didn't understand...Why should it be with those particular limits
I don't understand? I think you didn't understand. I stated in my very first post, post number 6.

http://talkstats.com/showpost.php?p=38964&postcount=6

"Different bounds are needed. "

It took you a while to realise this
Why was I stating that this will not work with the bounds you provided when we integrate in different order? Because your solution is incomplete. Once again, remember the properties of a valid joint pdf.

4. ## Re: Joint PDF problem

Originally Posted by Martingale
you obviously don't know what you are talking about.
Yes, I do

That's better! Much better

though I already showed that it integrated to 1 so this is just a waste of time.
It's not. The solution was not complete. But you now you have shown it in different order... So, problem solved.

5. ## Re: Joint PDF problem

Originally Posted by _joey
Yes, I do

That's better! Much better

It's not. The solution was not complete. But you now you have shown it in different order... So, problem solved.

The solution was complete. f(x,y)>=0 and it integrated to 1. geesh

6. ## Re: Joint PDF problem

Originally Posted by Martingale
The solution was complete. f(x,y)>=0 and it integrated to 1. geesh
I wouldn't be giving you full marks if I was checking your work. But thanks for replies anyway

7. ## Re: Joint PDF problem

Originally Posted by _joey
I wouldn't be giving you full marks if I was checking your work. But thanks for replies anyway
Again you clearly don't know what you are talking about. I'm also betting that you didn't even know how to switch the limits (even though it is a simple undergraduate problem)

Anyway this discussion is over.