Why you need to know about Expected Value

You've been using a 30-pip trailing stop for as long as you can remember. It feels professional, manageable and relatively safe. 

But during volatile sessions, you see your winners get stopped out prematurely, while low-volatility winners drift back and hit stops that are relatively too tight. 

Same 30 pips, different market contexts, but inconsistent in the protection of profit and overall results.

The Fixed-Pip Fallacy?

Traders gravitate toward fixed pip trailing stops because they feel concrete and calculable. The approach is easy to execute, readily automated through platforms like MetaTrader, and aligns with how most people naturally think about profit and loss. 

But this simplicity masks a fundamental problem. 

A twenty-five pip move in EURUSD during the London open represents an entirely different market event than the same move during the Asian session. The context matters, yet the fixed-pip approach treats them identically. 

This becomes even more problematic when you consider different currency pairs. GBPJPY might have an average true range of thirty pips on an hourly chart, while EURGBP shows only ten. The same trailing stop applied to both instruments ignores the reality that volatility varies dramatically across pairs.

Timeframe introduces yet another layer of complexity. Take AUDUSD as an example: a ten-pip move on a four-hour chart barely registers as meaningful price action, but on a five-minute chart it represents a significant swing. The fixed-pip method treats these scenarios as equivalent.

The natural response might be to use something more sophisticated, like an ATR multiple. This accounts for your chosen timeframe, the instrument's normal volatility, and even session differences. But it brings its own complications. 

When do you measure the ATR? Do you use the value at entry, knowing it might be distorted by sessional effects? Or do you make it dynamic, which becomes far more complex to implement in practice?

Perhaps there's another way forward that doesn't rely on abstract measures of volatility but instead responds directly to the movement of price in relation to the trade you're actually in—accounting for your lot size and the profit you've already captured. 

Maximum Give Back: The Percentage Approach

Instead of asking "how do I protect profit after fifty pips," ask "how do I protect profit after giving back a certain percentage of open gains." 

Consider a maximum give-back threshold of 40%. When your trade is up one hundred pips, the trailing stop activates if price retraces forty pips from peak, locking in a minimum of sixty pips. 

But when that same trade reaches two hundred fifty pips of profit, the stop adjusts, and now it activates at a one-hundred-pip pullback, securing at least one hundred fifty pips. The stop distance scales naturally with the magnitude of the win you're sitting on.

This creates a logical asymmetry that fixed pip approaches miss entirely. Small winners receive tighter protection. Big winners get room to breathe.

The approach adapts automatically to what the market is actually giving you in real time, without requiring you to predict anything in advance. 

You don't need to maintain a reference table where EURUSD gets thirty pips and GBPJPY gets sixty. You don't need different standards for different instruments at all. 

The same 40% logic works whether the average true range is high or low, whether volatility is expanding or contracting. It survives regime changes without requiring recalibration because it's responding to the trade itself rather than to abstract measures of what the instrument normally does.

The market tells you how much it's willing to move in your direction, and you protect that information proportionally. Nothing more complicated than that.

Key Parameters to Specify in Your System:

• Maximum Give Back Percent: 30-50% is typical, but is dependent on how much profit retracement you can tolerate. 
• Minimum Profit to Activate: In dollar amount or an ATR multiple form entry. This prevents premature exits on tiny winners, e.g., if it has moved 5 pips at 40% that would mean you are only locking in a 3-pip profit.
• Update Frequency: Potentially every bar. More frequent, but there may be issues if there is a limited ability to look at the market (if using some sort of automation, this could be programmed).

Is Maximum Giveback Always the Optimum Trail?

As with many approaches, results can be highly dependent on underlying market conditions. It is important to be balanced. 

The table below summarises some observations when maximum giveback has been used as part of automated exits.

The major difference isn’t likely to be an increased win rate. It is about keeping more of your runners during high-volatility price moves rather than donating them back to the market.

It may not always be the best approach, as different strategies often merit different exit approaches.  

There are two obvious scenarios where fixed pips may still be worth consideration.

• Very short-term scalping (sub-20 pip targets)
• News trading, where you want instant hard stops

Integrating Maximum Giveback With Your System 

You may have other complementary exit filters in place that you already use. Remember, the ideal is often a combination of exits, with whichever is triggered first.

There is no reason why this approach will not work well with approaches such as set stops, take profits and partial closes (where you simply use maximum Giveback in the remainder as well as time-based exits.

Final Thoughts

To use fixed-pip trailing stops irrespective of instrument pricing, volatility, timeframe, and sessional considerations is the trading equivalent of wearing the same jacket in summer and winter. 

Maximum Give Back trailing adjusts to the ‘market weather’. It won't make bad trades good, but it will stop you from cutting your best trades short just because your stop was designed for average conditions. 

The market doesn't trade in averages but has specific likely moves dependent on context. Your exits should not be average either. 

You have just identified a breakout above $50 resistance that historically wins 65% of the time — with a degree of confidence, you decide to take the trade.

Minutes later, the market starts to stall. Volume fades, price begins to hesitate, and eventually, your stop loss is hit, leaving you to wonder why your “65% setup” didn’t work.

The root cause of what happened is not your setup, but rather the fact that you assume that the probability of a specific trade outcome stays constant after entry.

This assumption locks you into a “static probability trap.” 

There is a tendency to treat probability as frozen in time after entering a trade, when in practice it shifts continuously throughout the life of a trade as new evidence enters the market.

Even if this new evidence may not be particularly dramatic, it can still have profound implications for the likelihood of a continuation of current sentiment and price action.

Unconditional Probability: Your Pre-trade State.

What you can rely on as part of your pre-entry decision-making is unconditional probability. 

This is your measured historical performance of a setup under similar conditions. It is your expected win rate and previous evidence of hitting a take-profit level.

The pre-trade belief that “This pattern works 60% of the time” is a backward-looking statement, and although based on some evidence, it shapes your belief about how this type of setup behaves on average.

However, as soon as you enter, the truth is that you are no longer dealing with a statistical average, but with this specific trade, unfolding before your eyes in this market environment, right now.

Conditional Probability: After You Enter

Once in the trade, your question becomes “Given what’s happening now with current price movement, volume, time, and volatility,  what’s the probability of success?”

This live review of your pre-trade expectation is the conditional probability — your new probability estimate conditioned on the actual market response that is unfolding.

Each new candle, volume shift, or volatility change is new information, irrespective of the underlying cause, and information changes probability. 

You are looking to see if:

• Trading volume is confirming or rejecting your entry expectations.
• If “time in the trade” supports further price moves in your favour or decay in market enthusiasm, evidenced in a drop in momentum.
• There are volatility changes that may be indicative of market sentiment accelerating or rejecting the initial move.

This is all about you recognising that some of these changes may result in adverse price moves. Having timely interventions that aim to protect capital and not donate much of your profit back to the market. 

Emotional Resistance to Conditional Probability Thinking

As with many trading situations, there is a psychological component of decision-making that can get in the way. 

Emotional “demons” that may influence this may briefly include the following: 

1. Anchoring: “I have done my analysis — it should work.”
2. Sunk-Cost Bias: “I’m already in, I might as well wait and see what happens next.”
3. Ego: Some may view that exiting means admitting they were wrong.
4. Lack of knowledge: “I don’t know how to update probabilities or take appropriate actions.” 
5. FOMO (fear of missing out): “What if I exit and then runs in my favour?”

These biases keep traders fixed at entry from mental, emotional, and statistical perspectives. 

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Updating Probability in Real Time

When you boil it all down into absolute core principles, three critical factors dominate the “in the trade” probability landscape after trade entry.

1. Trading Volume — Conviction or Rejection

Volume is the purest signal of conviction. It shows the strength behind the move and how much belief the market has in your trade direction. 

• High volume in your direction = strong confirmation; probability rises.
• Fading or below-average volume = weak conviction; probability erodes.
• High volume against you = rejection; probability collapses.

You can think of volume as your real-time market feedback gauge. It is the purest real-time evidence, in combination with price, of what other traders are thinking.

When price and volume disagree, this is a signal that the odds may (or already have) changed.

2. Time Elapsed — Pattern Decay

Every trade setup has a shelf life. A breakout that has not moved after a few candles can become statistically weaker than one that fired almost immediately. 

The potential scenarios are:

• Quick follow-through: expected behaviour; your entry probability is likely to be intact.
• Extended stagnation: increasing probability decay due to trades losing confidence in the trade direction
• Delayed reversal: final evidence of pattern failure.

Each candle that passes without confirmation can be viewed as a ‘vote’ against your trade from the market. 

This dissuades further trading interest in your desired direction, as opposed to when a market is enthused and buying seems to create ever-increasing interest as those who are fearful of missing out jump on board.  

3. Volatility Regime — The Environment Shift

Volatility defines your market environment, and this environment can change fast. 

• Volatility expansion in your favour confirms momentum; the probability of desirable and expected outcomes increases.
• Volatility expansion against you suggests a potential structural shift in the market, resulting in a fast drop in probability.
• Volatility contraction suggests market consolidation or exhaustion. This may be seen as a flattening of price action and a move from strongly directional to a more neutral price move. 

Volatility regime shifts are a potential market indication that “the game when you entered is no longer the same.”

Putting It All into Practice: Your End-of-Candle Review

Managing conditional probability doesn’t mean reacting to every tick. It is formalising a systemised reassessment at defined intervals, often doing an “End-of-Candle Review”, on your chosen trading timeframe as a start point.

At the close of each bar on your trading timeframe, you need to pause and ask the following key questions:

1. Has price behaved as expected?
   
   • Yes → maintain or increase confidence.
   • No → reduce exposure or prepare to exit.
2. Is volume confirming or fading?
   
   • Rising with direction → edge intact.
   • Falling or reversing → edge weakening.
3. Is volatility expanding or contracting?
   
   • Expanding in your favour → stay the course.
   • Contracting or reversing → reassess.
4. Has too much time passed without progress?
   
   • Yes → probability decay in play; consider exiting or scaling out.
5. What’s the appropriate action?
   
   • Hold, reduce, tighten, or exit — but always act in alignment with the evidence.

This simple routine keeps your decision-making informed by data, adaptable to market change, and unemotional.

None of the above is particularly ‘rocket science,’ but as with most things in your trading, it will require some work at the front end. 

Measure the “what if” scenario against previous trades and comparatively measure your old way versus your new system over time to allow for confirmation of this as an approach, but also to allow refinement based on evidence.

Final thoughts

The probability of a trading outcome in a single trade is never static. It evolves with every candle, every shift in volume, and every minute of market time as new information is released.

It does require a mindset shift. As traders, we need to move from the standard “It’s a 65% setup, so I’ll hold.” To an approach that adopts the approach of “It was a 65% setup on entry, but what is the market evidence suggesting now?” 

You are reacting to evolving information, and effective probability management becomes something beyond having one good trade (or avoiding a bad one) that compounds small improvement over hundreds of trades into measurable performance.

Most traders understand EA portfolio balance through the lens of traditional risk management — controlling position sizes, diversifying currency pairs, or limiting exposure per trade.

But in automated trading, balance is about deliberately constructing a portfolio where different strategies complement each other, measuring their collective performance, and actively managing the mix based on those measurements.

The goal is to create a “book” of EAs that can help diversify performance over time, even when individual strategies hit rough patches.

A diversified mix of EAs across timeframes and assets can, in some cases, reduce reliance on any single strategy. This approach reduces dependency on any single EA’s performance, smooths your overall equity curve, and builds resilience across changing market conditions.

It’s about running the right mix, identifying gaps in your coverage, and viewing your automated trading operation as an integrated whole rather than a collection of independent systems.

Basic Evaluation Metrics – Your Start Point

Temporal (timeframe) Balancing

When combined, a timeframe balance (even on the same model and instrument) can help flatten equity swings.

For example, a losing phase in a fast-acting M15 EA can often coincide with a profitable run in an H4 trend model.

Combining this with some market regime and sessional analysis can be beneficial.

Asset Balance: Managing Systemic Correlation Risk

Running five different EAs on USDJPY might feel diversified if each uses different entry logic, even though they share the same systemic market driver.

But in an EA context, correlation measurement is not necessarily between prices, but between EA returns (equity changes) relating to specific strategies in specific market conditions.

Two EAs on the same symbol might use completely different logic and thus have near-zero correlation.

Conversely, two EAs on a different symbol may feel as though they should offer some balance, but if highly correlated in specific market conditions may not achieve your balancing aim.

In practical terms, the next step is to take this measurement and map it to potential actionable interventions.

For example, if you have a EURUSD Trend EA and a GBPUSD Breakout EA with a correlation of 0.85, they are behaving like twins in performance related to specific market circumstances. And so you may want to limit exposure to some degree if you are finding that there are many relationships like this.

However, if your gold mean reversion EA correlates 0.25 compared to the rest of your book, this may offer some balance through reducing portfolio drawdown overlap.

Directional and Sentiment Balance

Markets are commonly described as risk-on or risk-off. This bias at any particular time is very likely to impact EA performance, dependent on how well balanced you are to deal with each scenario.

You may have heard the old market cliché of “up the staircase and down the elevator shaft” to describe how prices may move in alternative directions. It does appear that optimisation for each direction, rather than EAs that trade long and short, may offer better outcomes as two separate EAs rather than one catch-all.

Market Regime and Volatility Balance

Trend and volatility states can have a profound impact on price action, whether as part of a discretionary or EA trading system. Much of this has a direct relationship to time of day, including the nature of individual sessions.

We have a market regime filter that incorporates trend and volatility factors in many EAs to account for this. This can be mapped and tested on a backtest and in a live environment to give evidence of strategy suitability for specific market conditions.

For example, mean reversion strategies may work well in the Asian session but less so in strongly trending markets and the higher volatility of the early part of the US session.

As part of balancing, you are asking questions as to whether you actually have EA strategies suited to different market regimes in place, or are you using these together to optimise book performance?

The table below summarises such an approach of regime vs market mapping:

Multi-Level Analysis: From Composition to Interaction

Once your book is structured, the challenge is to turn it into something workable. An additional layer of refinement that turns theory and measurement into something meaningful in action is where any difference will be made.

This “closing the circle” is based on evidence and a true understanding of how your EAs are behaving together. It is the step that takes you to the point where automation can begin to move to the next level.

Mapping relationships with robust and detailed performance evaluation will take time to provide evidence that these are actually making a difference in meeting balancing aims.

To really excel, you should have systems in place that allow ongoing evaluation of the approaches you are using and advise of refinements that may improve things over time.

What Next? – Implementing Balance in Practice

Theory must ultimately translate into an executable EA book. A plan of action with landmarks to show progress and maintain motivation is crucial in this approach.

Defining classification tags, setting risk weights, and building monitoring dashboards are all worth consideration.

Advanced EA traders could also consider a supervisory ‘Sentinel’ EA, or ‘mothership’ approach, to enable or disable EAs dynamically based on underlying market metrics and external information integrated into EA coding decision-making.

Final Thoughts

A balanced EA portfolio is not generated by accident; it is well-thought-out, evidence-based and a continuously developing architecture. It is designed to offer improved risk management across your EA portfolio and improved trading outcomes.  

Your process begins with mapping your existing strategies by number, asset, and timeframe, then expands into analysing correlations, directional bias, and volatility regimes.

When you reach the stage where one EA’s drawdown is another’s opportunity, you are no longer simply trading models but managing a system of EA systems. To finish, ask yourself the question, “Could this approach contribute to improved outcomes over time?”. If your answer is “yes,” then your mission is clear.

If you are interested in learning more about adding EAs to your trading toolbox, join the new GO EA Programme (coming soon) by contacting [email protected].