Parabolic Weighted Moving AverageThe weights of this moving average are powers of the weights of the standard weighted moving average  WMA .
Remember:
 
  When parameter  Power  = 0, you will get  SMA .
  When parameter  Power  = 1, you will get  WMA .
 
Good luck!
Smoothing
Kalman SmootherA derivation of the Kalman Filter.
Lower  Gain  values create smoother results.The ratio Smoothing/Lag is similar to any  Low Lagging  Filters.
The  Gain  parameter can be decimal numbers.
 Kalman Smoothing With Gain = 20 
  
  For any questions/suggestions feel free to contact me
One Dimensional Parametric Kalman FilterA One Dimensional Kalman Filter, the particularity of Kalman Filtering is the constant recalculation of the  Error  between the measurements and the estimate.This version is modified to allow more/less filtering using an alternative calculation of the error measurement.
Camparison of the Kalman filter  Red  with a moving average  Black  of both period 50
  
Can be used as source for others indicators such as stochastic/rsi/moving averages...etc
 For any questions/suggestions feel free to contact me 
On Balance VolumeThis indicator was originally described by Joseph E. Granville in his book "Granville's New Key To Stock Market Profits" (1963).
Moving Average 3.0 (3rd Generation)Moving Average 3.0 (3rd Generation) script.
This indicator was originally developed and described by Dr. Manfred G. Dürschner in his paper "Gleitende Durchschnitte 3.0".
Ehlers StochasticEhlers Stochastic script.
This indicator was originally developed by John F. Ehlers (Stocks & Commodities V. 32:1: Predictive And Successful Indicators).
Ehlers Super Smoother FilterEhlers Super Smoother Filter script. 
This indicator was originally developed by John F. Ehlers (see his book `Cybernetic Analysis for Stocks and Futures`, Chapter 13: `Super Smoothers`).
Ehlers Leading IndicatorEhlers Leading Indicator script. 
This indicator was originally developed by John F. Ehlers (see his book `Cybernetic Analysis for Stocks and Futures`, Chapter 16: `Leading Indicators`).
Quadratic RegressionA quadratic regression is the process of finding the equation that best fits a set of data.This form of regression is mainly used for smoothing data shaped like a parabola.
Because we can use short/midterm/longterm periods we can say that we use a Quadratic Least Squares Moving Average or a Moving Quadratic Regression.
Like the Linear Regression (LSMA) a Quadratic regression attempt to minimize the sum of squares (sum of the squared difference between a set of data and an estimator), this is why
those kinds of filters have low  lag .
Here the difference between a Least Squared Moving Average ( green ) and a Quadratic Regression ( red ) of both period 500
  
Here it look like the Quadratic Regression have a best fit than the LSMA
Hamming Windowed Volume Weighted Moving AverageApplying a window to the filter weights provides sometimes extra control over the characteristics of the filter.In this script an hamming window is applied to the volume before being used as a weight.In general this process smooth the frequency response of a filter.
Lets compare the classic vwma with hamming windowed vwma
  
Something i noticed is that windowed filters depending on their period ( high ones in general ) tend to make less bad crosses with the price ( at least with the hamming window )
Here are some data regarding number of crosses with period 50 with the hamming vwma in orange and the classic vwma in purple 
  
Feel free to use the hamming window when using weighted filter.
Double Exponential SmoothingSingle Exponential Smoothing ( ema ) does not excel in following the data when there is a trend. This situation can be improved by the introduction of a second equation with a second constant  gamma .
The  gamma  constant cant be lower than 0 and cant be greater than 1, higher values of  gamma  create less lag while preserving smoothness.Higher values of  length  must be followed by higher values of  gamma  in order to keep the lag low.
The first smoothing part consist of a classic ema but we add  s-s1  to the previous smoothed value, this will help decrease lag.The second smoothing part then updates the trend, which is expressed as the difference between the last two values.
Holt Exponential Moving AverageHolt Exponential Moving Average indicator script.
This indicator was originally developed by Charles C. Holt (International Journal of Forecasting 20(1):5-10, March 2004: Forecasting seasonals and trends by exponentially weighted moving averages). 
Auto-FilterA least squares filter using the Auto line as source, practical for noise removal without higher phase shift.
Its possible to create another parameter for the auto-line length, just add a parameter  Period  or whatever you want.
 r = round(close/round)*round
dev = stdev(close,Period) 
Hope you enjoy :)














