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Edge Ratio Measures Entry Quality, Not Overall Strategy Performance

Article Quant Q&A · Author: 4488970
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Summary

The document discusses the edge ratio as a tool for evaluating the entry component of an algorithmic trading system. It presents two limitations: unlike the Sharpe ratio, the edge ratio is not commonly requested by investors, and its statistical properties are described as less well established. The response also questions whether a high edge ratio implies a high probability of investment success, whereas a high signal-to-noise ratio is linked to Roy’s safety-first argument.

A second answer clarifies the metric’s intended scope: it helps assess entry quality and may help investigate average holding length, but it does not measure the complete strategy’s performance. The practical distinction is between using the ratio during strategy development and using performance measures to assess a finished system. The document offers no formal definition, calculation example, or empirical comparison, so it raises concerns rather than proving that the edge ratio is unsuitable.

Key ideas

  • The edge ratio is presented as a diagnostic for entry quality rather than a full strategy score.
  • Its statistical behavior is described as less studied than that of the Sharpe ratio.
  • The document questions whether a high edge ratio implies a high probability of investment success.
  • The ratio may help investigate entry timing and average holding length during system development.

Tags

BacktestingStatisticsRisk management
Full text
# What is the disadvantage using the edge ratio?


# What is the disadvantage using the edge ratio?












I want to evaluate and optimize an algorithmic trading system. For this I want to follow a step by step approach - first looking at the entry, later at other aspects of it (money management, position management, exit management etc.)

I discovered the edge ratio or eratio (see edge ratio) that also exists in some variations (see edge of an entry signal).

I got the impression that the edge ratio is not so much used as compared to other figures/techniques like the Sharpe ratio, a mae mfe analysis etc.

I would like to know whether there is any disadvantage of using the edge ratio.

## Answer by steveo'america (score 4)

https://quant.stackexchange.com/a/55986

I can think of a number of reasons not to use the "e-ratio":

- Potential investors will routinely ask about your Sharpe ratio, but I have never heard of one using the edge ratio.

- The statistical properties of the Sharpe ratio are well understood, whereas the edge ratio seems not to have been well studied.

- By Chebyshev's inequality, a high Sharpe ratio (well, signal-noise ratio) translates to a high probability of positive returns. This is Roy's "Safety First" argument. It is not clear that a high edge ratio translates to a high probability of "success" of an investment, however you measure that.

## Answer by babelproofreader (score 4)

https://quant.stackexchange.com/a/57027

The e-ratio is simply a tool to measure the quality of entries and it says nothing about the overall performance of a trading strategy. It answers the question "Is this a good entry technique?" and perhaps "What is the optimum average holding length?"

It is a strategy development tool, not a strategy assessment tool.

Shown in full with attribution under the source's licence. Licence: CC BY-SA 4.0 (Stack Exchange)

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.