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View Full Version : Giving Two Percentages One Value under the same entity


lvv328
Feb 2, 2010, 10:03 PM
Say that I have one entity that has two traits that have percentages of activating, we will put it in terms of money.

20% chance of $27
31% chance of $9

How do I put this into one value so that I can compare this entity to other entities that have only one trait available such as:

94% chance of $8

ebaines
Feb 3, 2010, 11:17 AM
Not sure I totally understand the question, but let me suggest this:

If you know the probability of each possible outcome, you can calculate an "expected value" for the process and then compare that. In your example you have 20% chance of $27 and 31% chance of $9. You don't tell us what happens the other 49% of the time, and for this to work we need to have probabilities that add to 1. For the sake of the example - if I assume that there is a 49% chance of $0, then the expected value is:

0.20 * $27 + 0.31* $9 + 0.49 * $0 = $8.19

This means if you run this process many times over, your average return for each run is expected to be $8.19.

Does this help?

lvv328
Feb 3, 2010, 04:48 PM
Thanks! That did help a lot. I was not considering that there could be a possibility of a 0 amount.