### Welford Variance VertexFX Indicator

Posted:

**Wed Oct 09, 2019 10:04 am**The Welford Variance indicator is a useful VertexFx client-side indicator for identifying trend changes on higher time-frames.

It calculates the standard deviation and variance of the price changes over the Variance Period (VAR_PERIOD), and then smoothes it using a smoothing co-efficient. The Welford Variance indicator should be used in combination with other trend-following oscillators like Relative Strength Index (RSI), Moving Average Convergence Divergence (MACD) or Stochastic Oscillator.

The standard deviation defines how much the current price is deviating from the mean price. Higher the standard deviation, greater is the volality. In the first step, we calculate the mean and standard deviation of the recent VAR_PERIOD candles. In the next step, we calculate the variance by subtracting the price from the standard deviation. Finally, we smooth the variance, using the co-efficient, which is reciprocal of (1 + VAR_PERIOD). When the variance increases, the probabilty of fast price movement in the current direction is very high. As a result the Welford Variance indicator can provide powerful trade entries with minimal lag.

BUY / EXIT SHORT - Enter LONG (or exit SHORT) at the close after the Welford Variance indicator has bottomed out and is rising, and other confirmation indicator like RSI, MACD or Stochastic Oscillator has turned bullish. The stop-loss can be set to the nearest Swing Low.

SHORT / EXIT LONG - Enter SHORT (or exit LONG) at the close after the Welford Variance indicator has peaked out and is falling, and other confirmation indicator like RSI, MACD or Stochastic Oscillator has turned bearish. The stop-loss can be set to the nearest Swing High.

It calculates the standard deviation and variance of the price changes over the Variance Period (VAR_PERIOD), and then smoothes it using a smoothing co-efficient. The Welford Variance indicator should be used in combination with other trend-following oscillators like Relative Strength Index (RSI), Moving Average Convergence Divergence (MACD) or Stochastic Oscillator.

The standard deviation defines how much the current price is deviating from the mean price. Higher the standard deviation, greater is the volality. In the first step, we calculate the mean and standard deviation of the recent VAR_PERIOD candles. In the next step, we calculate the variance by subtracting the price from the standard deviation. Finally, we smooth the variance, using the co-efficient, which is reciprocal of (1 + VAR_PERIOD). When the variance increases, the probabilty of fast price movement in the current direction is very high. As a result the Welford Variance indicator can provide powerful trade entries with minimal lag.

BUY / EXIT SHORT - Enter LONG (or exit SHORT) at the close after the Welford Variance indicator has bottomed out and is rising, and other confirmation indicator like RSI, MACD or Stochastic Oscillator has turned bullish. The stop-loss can be set to the nearest Swing Low.

SHORT / EXIT LONG - Enter SHORT (or exit LONG) at the close after the Welford Variance indicator has peaked out and is falling, and other confirmation indicator like RSI, MACD or Stochastic Oscillator has turned bearish. The stop-loss can be set to the nearest Swing High.