Introduction

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This indicator (the middle one in the image) shows how the "others altcoins" (all altcoins except coins with high capitalization) are adding own value to its capitalization by removing BTC price changes. By "own value" I mean USD value gaining by actual buys in BTC markets beyong arbitrage effects of BTC price changes.

The main idea is that, if bitcoin has increased is value by 20%, and the other altcoins has increased its capitalization by 30%, the chart will only plot an increased of 10%. In other words, it will show its increased capitalization measured in BTC (the combined altcoin/ BTC market is uptrending). Its purpose is to try to identify altseasons. A bit more concisely, the graph will only grow when both USD and BTC capitalization are growing. If any of them are going down, the graph will go down as well.

Rationale

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- Altseasons are characterized by an incresed in BTC value of almost every altcoin during some period of time, although not all at once, but distributed over the altseason. For example, in the crazy altseason of Dec17/Jan18, almost every (low capitalized) altcoin increased its BTC value by a minimum of +300%, some at the beginning of the season, some at the end.

- When this happens, BTC loss capitalization dominance, but this also can happen if BTC is downtrending while altcoins are being bought in BTC markets but its USD value doesn't change too much. This happens when altcoins are uptrending in BTC price, but there are actually no gain of USD value because the BTC gain in value is not enough to compensate the BTC fall in price. Since BTC is losing USD price, but altcoins are not, dominance falls. So, looking at BTC dominance is not enough to spot possible beginnings of altseasons, because of arbitrage of other effects.

- The "big altcoins" are removed from the counting because one single big capitalized altcoin that grows, let's say, a 20%, will have an observable effect on the total altcoin capitalization, even if the rest of the altcoins are stagnated in price. For example, at today's date (8th April 2020), Ethereum by itself has the 23.89% of the total altcoins capitalization. A +10% in Ethereum price will increase the total altcoin capitalization by a +2.38%. I wanted to remove that effect to focus on generalized price changes of all altcoins. Remember that there are only 9 big altcoins 9 coins representing the 71% of the alts capitalization, while there are exists more than 5000 altcoins in total.

- Another key factor is that I want to focus on what happens in alt/ BTC markets, because almost every altcoin can be traded against BTC , and most of them can only be traded against BTC . However, big altcoins can usually be traded against USD or other alt coins or fiat currencies as well. Removing the big alts from the equation helps (just a bit) to simplify the interpretation of the chart because arbitrage effects of those "impactfull" alts are limited (although not removed, because arbitrage also happens cross-markets).

- There are situations where BTC price is going up, alts USD capitalization is going up as well, but alts BTC capitalization is going down because altcoins are being sold in BTC markets, it just happens that the speed of the selling is not high enough as to compensated the increased in BTC price. That makes the USD capitalization grows, while alts are really being dumped in BTC markets. I wanted to reflect that effect as well by making sure that the graph is growing only when both USD and BTC capitalization of alts are growing.

Interpretation

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If you want, you can see this chart as if plotting the Other alts capitalization as if priced against a fictional coin FCOIN, that start by having a price of 1, that combines the up and downs of both BTC price and alts USD capitalization in a very conservative way: if FCOIN price goes up, means that the other alts are gained USD value but only when they have overcome BTC price changes. Otherwise, it goes down.

If this fictional FCOIN has went up during some days straight with a total gain of maybe, greater than 10%, we are maybe in front of the start of an altseason. Sometimes, maybe (it requires some more years to extract a theory out of here), it can be used as proxy of the BTC near future (trend changes or continuations): if this FCOIN goes up, while BTC is doing nothing relevant or even is going down, it could signal that "people" is getting prepared and a generalized altcoin accumulation process has started, because of a combined people's assumption that BTC will start to have an stable uptrend, or will continue the current trend soon. There's some matches in the past about that, but there are also false positives, as usual.

Additionally, four customizable EMAs are added to the script, by default 21, 50, 100 and 150.

Definitions

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- Let's call `altcap_btc` the altcoin capitalization in USD, divided by BTC price. In other words, `altcap_btc` is the capitalization in terms of BTC .

- Let's call `x` the BTC price change rate as `btc_price_current_candle / btc_price_previous_candle`. So, if BTC has grown a +20%, `x = 1.20`, and if BTC has gone down a -20%, `x = 0.80`.

- Let's call `y` the `altcap_btc` price change rate, calculated as before but for `altcap_btc`.

- For pure math equivalence, `x * y` is thus the USD capitalization change rate.

Calculation

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For plotting the graph, for each candle, I choose a change rate, and then I plot the total accumulated change rate as by `ch0 * ch1 * ch2 * .... * ch_today`, where each `chX` is the choosen change rate of each candle since the beginning of the chart. So, if the "alts compensated value" has grown yesterday +20% and today's -10%, `1.20 * 0.9 = 1.08`, which means that in two days the compensated value has grown an 8% in total.

- If `x * y > 1` (USD cap is growing), I take `y` as change rate (alt/ btc change rate).

- If both `x` and `y` are `> 1`, then the graph grows because I'm taking `y`.

- If `x > 1` and `y < 1`, the graph goes down because I'm taking `y`, reflecting the BTC markets are dumping.

- If `x < 1` and `y > 1`, the graph goes up because I'm taking `y`, reflecting the BTC markets are pumping so much that it overcomes the btc fall.

- `x < 1` and `y < 1` is impossible here because `x * y` must be `> 1` by precondition.

- If `x * y < 1` (USD cap is going down), I take `y` or `x * y` depending on the individual change rates:

- If `x` and `y` go in different directions (one up and the other down), I take `x * y` to reflect that USD capitalization has gone down. I don't take `y` here because it could be `> 1`, and I don't want to make the graph grow if alts are lossing USD value. Also, if `y < 1` and I take `y` the graph will go down faster than USD capitalization and I want to show that "alts compensated value is gown down slower than BTC because some boughts are happening". I don't take `x` either here for the same reasons.

- If both `x` and `y` are `< 1`, I take `y`, because otherwise the graph would be less than 0.000001 today after two years of bleeding, making literally impossible to see if alts "grow tomorrow".

- `x > 1` and `y > 1` is impossible here because `x * y` must be `< 1` by precondition.

Notes de version:
Grammar fix.

Notes de version:
The script is now open source.

Notes de version:
Cosmetic changes.