- #1

- 95

- 0

## Main Question or Discussion Point

I don't see how this is possible? how can you have a distrubution with no mean?

My professor says there is, but i don't get it...

My professor says there is, but i don't get it...

- Thread starter Physics is Phun
- Start date

- #1

- 95

- 0

I don't see how this is possible? how can you have a distrubution with no mean?

My professor says there is, but i don't get it...

My professor says there is, but i don't get it...

- #2

matt grime

Science Advisor

Homework Helper

- 9,395

- 3

a_1+a_2+....

that has a finite sum (and hence is can be made to have sum 1, and be a prob distribution on N) but where a_1+2a_2+3a_3+... is not finite (so there isn't a mean).

And there are less contrived examples too.

- #3

mathman

Science Advisor

- 7,741

- 406

Simple example a_k=1/k^2

- Replies
- 2

- Views
- 11K

- Last Post

- Replies
- 4

- Views
- 560

- Replies
- 5

- Views
- 390

- Replies
- 8

- Views
- 4K

- Replies
- 5

- Views
- 558

- Replies
- 4

- Views
- 2K

- Replies
- 2

- Views
- 723

- Last Post

- Replies
- 3

- Views
- 1K