1. ## Need exact definition.

Hi everyone! Guys, please need your help. I want to know what difference between discrete and continuous variable. I understand that is easy question but google and wiki doesnt give right definition. Any advice... I will appreciate it.

2. ## Re: Need exact definition.

The sample space of a discrete variable is countable. That of a continuous variable is not.

3. ## Re: Need exact definition.

Like fun you are right. I found interesting example - length for example is continuous you can get any value 3 3.1 3.1235 3.12323455333
But if you measure the length in the centimeters only (3cm, 4cm, 5cm) it is a discrete variable.
the number of children is discrete, you can't have 3.123 children in the class.

4. ## Re: Need exact definition.

By the way romsek you was right. And thanx for help.

5. ## Re: Need exact definition.

Originally Posted by Tris
you can't have 3.123 children in the class.
nah, 0.123 child probably isn't enough for it to be in a class.

You might be able to get away with 0.5 child and up if the appropriate bits were present!

6. ## Re: Need exact definition.

Why? Can you explain?

7. ## Re: Need exact definition.

it's a joke.... if perhaps a sick and macabre one

0.123 of a child is just a leg or so. Not much reason to try and educate a leg.

At 0.5 of a child you have enough there to probably keep them alive and thus educatable

8. ## Re: Need exact definition.

Originally Posted by romsek
0.123 of a child is just a leg or so. Not much reason to try and educate a leg.
What if that 0.123 part is the brain?

9. ## Re: Need exact definition.

Originally Posted by Tris
Hi everyone! Guys, please need your help. I want to know what difference between discrete and continuous variable. I understand that is easy question but google and wiki doesnt give right definition. Any advice... I will appreciate it.
There are some concepts that are not understandable if a person's background is not sufficient to support the explanation.
This is one such example. Here is a simple example:
Suppose that $\mathscr{D}$ is the set of all rational numbers in $[0,1]$ and $\mathscr{I}$ is the set of all irrational numbers in $[0,1]$
Now $\mathscr{D}$ is a discrete set while $\mathscr{I}~$ is a continuous set.

Now I fully understand if one does not follow that, but in fact that makes my point.

10. ## Re: Need exact definition.

Originally Posted by Monoxdifly
What if that 0.123 part is the brain?
good luck keeping it alive