[blackcat] L2 Ehlers FRAMA

17 thg 11, 2020

Level: 2

Background

John F. Ehlers introuced Fractal Adaptive Moving Average (FRAMA) in 2004.

Function

The objective of using filters is to separate the desired signals from the undesired signals (or noise). The practical application of moving averages often involves a tradeoff between the amount of smoothness required and the amount of lag that can be tolerated. Moving averages have this problem because the price data is not stationary, and may have different bandwidths over different time intervals. Various momentum-adaptive filtering techniques have been developed to take advantage of the nonstationary structure of prices. Adaptive filters have also been developed based on price statistics and the cyclic content of the price data . Dr. Ehlers described a different class of filters that monitor a different measure of temporal nonstationarity and alters their bandwidth in response to this measure.

There is no argument that market prices are fractal. Fractal shapes are self-similar because they tend to have the same roughness and sparseness regardless of the magnification used to view them. If you remove the labels from a 5 minute chart, a daily chart, and a weekly chart you would have difficulty telling them apart. This is the characteristic that makes them fractal. The self-similarity can be defined by the fractal dimension that describes the sparseness at all magnification levels.

To determine the fractal dimension of a generalized pattern, Dr. Ehlers cover the pattern with a number “N” of small objects of several various sizes “s”. As with any moving average, we are forced to compromise between responsiveness and smoothness. FRAMA can be a valuable weapon in your arsenal of technical indicators. It rapidly follows significant changes in price but becomes very flat in congestion zones so that bad whipsaw trades can be eliminated.


Key Signal

Filt --> FRAMA fast line
Trigger --> FRAMA slow line


Pros and Cons

100% John F. Ehlers definition translation, even variable names are the same. This help readers who would like to use pine to read his book.

Remarks

The 63th script for Blackcat1402 John F. Ehlers Week publication.

Readme

In real life, I am a prolific inventor. I have successfully applied for more than 60 international and regional patents in the past 12 years. But in the past two years or so, I have tried to transfer my creativity to the development of trading strategies. Tradingview is the ideal platform for me. I am selecting and contributing some of the hundreds of scripts to publish in Tradingview community. Welcome everyone to interact with me to discuss these interesting pine scripts.

The scripts posted are categorized into 5 levels according to my efforts or manhours put into these works.

Level 1 : interesting script snippets or distinctive improvement from classic indicators or strategy. Level 1 scripts can usually appear in more complex indicators as a function module or element.

Level 2 : composite indicator/strategy. By selecting or combining several independent or dependent functions or sub indicators in proper way, the composite script exhibits a resonance phenomenon which can filter out noise or fake trading signal to enhance trading confidence level.

Level 3 : comprehensive indicator/strategy. They are simple trading systems based on my strategies. They are commonly containing several or all of entry signal, close signal, stop loss, take profit, re-entry, risk management, and position sizing techniques. Even some interesting fundamental and mass psychological aspects are incorporated.

Level 4 : script snippets or functions that do not disclose source code. Interesting element that can reveal market laws and work as raw material for indicators and strategies. If you find Level 1~2 scripts are helpful, Level 4 is a private version that took me far more efforts to develop.

Level 5 : indicator/strategy that do not disclose source code. private version of Level 3 script with my accumulated script processing skills or a large number of custom functions. I had a private function library built in past two years. Level 5 scripts use many of them to achieve private trading strategy.