80:20 - Time to negotiate

My rough notes on trying to model a formula for deciding between two choices, A and B.

There are two options, A and B. You are very much gravitated towards A. I will give this a score of 80. 80 because it is close to certainty but not yet certain. Only things beyond 90 inches to certainty. 50/50 is when you aren't sure. 60/40 is still in the uncertainty zone, IMO. Even the 70, on the other hand, is clarity and conviction towards A. If I follow Delta 4 framework by Kunal Shah, Here the Delta is 4. It 70/30 clarity rule is even practiced by Amazon in decisions making if I recall correctly. But for critical decisions, where speed still matters, 80/20 is a one. It provides a balance of clarity and certainty. 70/30 for more speed. 

The thought came to me while driving yesterday morning. For A/B with initial weights as x/y and it to be x'/y'. A simple formula can work. We scale B to get the new ratios. k, a multiple of B to achieve the x'/y' 

k = (x⋅y′) ​/ (x′⋅y) 

Using this to change an 80/20 decision to 50/51, k needs to be greater than 4.08. 

To change it to 20/80, k needs to be greater than 16. This means B needs to be 16x better choice suddenly compared to A. 

What does this mean in the real world?

if you have two options, A and B. And you are 80% sure about A. You can negotiate for a B 4x better for it to win. And when you already have such a strong affinity towards A, sitting on the negotiation table doesn't harm. You come out with a 4x, or you have an A anyway. Who knows if you are even getting a 16x? It absolutely does not harm if you are comparing future optimistic value vs liquidity today.

Go, use the formula. To make it more robust, you can update it with an inflation factor for money, risk & opportunity cost for new opportunity cost, joy vs regret weightage for emotions, state of mind, etc.