It is a sentiment indicator. It uses data from Bitfinex longs chart and shorts chart. When ratio line going up it simply means most of the people from Bitfinex buying BTC when it goes down selling. So in this way we know bull and bear presure But it is only one exchange? Yes, but it is enough accurate for BTC, for ETH it is not so good.
How it works: With request security function was called the closes of longs and shorts charts and then with simple calculation was extracted a ratio of it and rescaled to make it easy to read. When ratio line moves up it gradualy changing background from -1 to 1 from red to green and vice versa to understad what is a trend or a majore sentiment of people After ratio was ploted, I created a smoothed ratio line with sma to extract signals from it buy and sell in a form of green and red circles.