# Need help translating idea in math formula

• Mar 11th 2007, 11:03 PM
Spa_R
Need help translating idea in math formula
Hi all, I need some help with 2 problems that I have. I have 2 ideas, related to set theory, and I would like to translate these ideas from words to math. Could you help me with that? How to translate the following 2 definitions into math?

- Definition 1 "Relevant Result": proportion of the list that contains at least 1 item from the list of Y, out of the total number of results for the query.

- Definition 2: proportion of the list that contains all items from the list of Y, so there is a perfect match, out the total number of "Relevant Results" according to Definition 1.

Both definitions are related to each other, but are at the same time separate metrics. Thanks!

• Mar 12th 2007, 12:01 AM
CaptainBlack
Quote:

Originally Posted by Spa_R
Hi all, I need some help with 2 problems that I have. I have 2 ideas, related to set theory, and I would like to translate these ideas from words to math. Could you help me with that? How to translate the following 2 definitions into math?

- Definition 1 "Relevant Result": proportion of the list that contains at least 1 item from the list of Y, out of the total number of results for the query.

- Definition 2: proportion of the list that contains all items from the list of Y, so there is a perfect match, out the total number of "Relevant Results" according to Definition 1.

Both definitions are related to each other, but are at the same time separate metrics. Thanks!

Can you give examples?

RonL
• Mar 12th 2007, 12:19 AM
Spa_R
Ok, it is related to search engines (information retrieval).

Let's say I have a list of information that I want to return, which I just call Y and consists of 4 items, so Y = {sunny, weather, holiday, florida}.

But I also got a list of items which I do not want, however, that lists contains texts. I go through this list, and try to match when at least one of these items occur once (definition 1) in a text, and when they occur all (definition 2). How to translate these ideas in mathematical notation? Thanks!
• Mar 12th 2007, 11:34 AM
Spa_R
A logical notation would also be ok...help?