Institutional Kelly-VAPS Risk Engine (Library) - library for MetaTrader 5

The Mathematical Flaw in Retail Risk

The vast majority of algorithmic trading robots fail because they rely on static lot sizing or arbitrary percentage-based risk models, retail developers calculate risk in a vacuum, ignoring real-time market structure. When macroeconomic volatility spikes, a static stop-loss distance is mathematically guaranteed to be absorbed by standard deviation expansion.

To survive algorithmic execution, risk must be dynamic, self-adjusting, and volatility-aware.

The Institutional Edge: Kelly-VAPS Architecture

The Kelly-VAPS (Volatility-Adjusted Position Sizing) Engine is a purely object-oriented C++ header file ( .mqh ) designed to be imported into professional Expert Advisors, it completely overrides standard position sizing functions by bridging two high-level quantitative models:

• The Kelly Criterion: Calculates the mathematically optimal fraction of the portfolio to risk based on the historical win rate and payoff ratio of your strategy.

• Volatility-Adjusted Sizing (VAPS): Normalizes the optimal Kelly risk against real-time market volatility using the Average True Range (ATR) and exact tick value constraints.

Core Architecture & Features

• Object-Oriented Design: Clean, modular class structure ( CKellyRiskEngine ) ready to be included via #include <Institutional_VAPS.mqh> in any EA.

• Dynamic Capital Protection: Automatically scales down exposure during erratic, high-volatility market regimes to prevent structural drawdowns.

• Margin Safety Protocols: Built-in safeguards check free margin and broker-specific maximum/minimum volume limits before returning the final lot size.

• Zero-Latency Math: Uses raw array pointers and memory-efficient formulas to execute complex risk calculations in nanoseconds without slowing down your OnTick execution loop.

How to Implement

1. Place the .mqh file in your MQL5/Include folder.

2. Call the library inside your EA and initialize the class.

3. Pass your current win-rate, payoff ratio, and target stop-loss points to the engine. The class will return the mathematically perfect lot size tailored to the live market tick.