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psandak
10.26.2012 , 08:13 AM | #9
Quote: Originally Posted by killahcheese View Post
wow nice calculation.
So is this saying that for ANY item you RE, it increase the chance of getting schematic?
There is a difference between chance and probability. What Felioats is calculating is the probability of success given a specific number of tries.

IMO a better visual is the probability of continued failure versus the fixed chance of success.

For a 20% RE on the first attempt your chance of failure is 80%. Simple enough. Now on the second attempt while the chance of success is still only 20%, the chance of two failures in a row is 64% (80%^2). Continuing the math the probability of...

3 failures in a row is 51.20% (80%^3) compared to 20% chance of success
4 failures in a row is 40.96% (80%^4) compared to 20% chance of success
5 failures in a row is 32.77% (80%^5) compared to 20% chance of success
6 failures in a row is 26.21% (80%^6) compared to 20% chance of success
7 failures in a row is 20.97% (80%^7) compared to 20% chance of success
8 failures in a row is 16.78% (80%^8) compared to 20% chance of success

Basically, if you get a schematic before the 8th try consider yourself lucky because you beat the odds.

on a 10% RE you have to go 21 consecutive failures before the odds tip in your favor. The probability of 21 failures in a row is 10.94% (90%^21) compared to 10% chance of success.

Then you have the law of averages to deal with. Perform millions of REs at 20% and the ratio of successes versus failures will work out to approximately one success to four failures (1:4). Another way to look at it is one in five attempts results in a success. The problem is when someone perform 20 REs at 20% and does not see that 1:4 ratio and they come to these forums to complain about it. They complain about not getting one schematic in 20 attempts but they "conveniently forget" the fact that they got two schematic is three tries a week ago . But this human nature - we tend to focus on the negative .