How is Tie Break Scored?

I am in a few online tournaments and I have a score which is the sum of my wins and half of my losses. However, I also have a Tie Break score. How is the tie break score calculated?

Thanks

it's the sum of

1. the scores of all the players you have beaten
2. half the score of all the players you have drawn

That makes sense. Thanks for the quick response!

so how is the basics tournament score calculated? In OTB tournaments it's calculated as the number of wins plus half the number of draws. That seems to apply and some of these online tournaments but many of the scores are different from that. What's going on? Is the system different from what I think or is there a glitch?

Thank you - your answer helped me figure it out, although it took me a little while. What confused me was the word "score", which I misinterpreted as "rating". I know, they are not the same, but that's where my brain went. So, for other folks who might make the same mistake, here's a slight modification to your (very adequate for most people) answer:

The Tie Break score is the sum of:

• The scores of all the players you defeated in the tournament, where 'score' refers to the player's final score in the tournament.
• One-half the scores of the players with whom you had a draw.

If you want to test this calculation, at the conclusion of a tournament:

1. Note the first player's Tie Break score. 
2. Then right-click on his or her name
3. Select View Game Archive. A new tab ("Archive") will open. The first five results will be the winner's tournament scores. 
4. For each player the winner defeated, go back to the Tournament tab (it will be something like "10|0 Rapid", depending on what kind of tournament it was), and find the defeated player's final score (in the Record column, the first number before the slash, e.g., if it is 3/5, then that player's score was 3). 
5. Do that for each player the winner defeated and sum the scores. 
6. Do the same for each player with whom the winner had a draw, sum the scores, and divide by two. 
7. Then add the sum of the defeated plus the sum of the drawn games, which should equal the winner's Tie Break score.

Was looking for this information. Thanks for this thread.