TradingView Backtest & Robustness Lab

Multi-Strategy Portfolio Backtesting: Correlation and Allocation

Multi-Strategy Portfolio Backtesting: Correlation & Allocation | SG Group

Backtest Learning ・ BT10

Multi-Strategy Portfolio Backtesting: Correlation and Allocation

Stacking individually good strategies is not diversification. The heart of a multi-strategy portfolio backtest is not comparing standalone results but testing correlation, aggregated profit and loss, post-allocation drawdown and simultaneous losses on returns aligned to a common time axis. This guide walks through building that shared foundation and separating apparent diversification from the real thing.

  • Standardizing before combining: period, currency, starting capital, cost and frequency
  • Why correlation is measured on common-axis return series, not on individual trades
  • A descriptive comparison of equal-capital, equal-risk, fixed-weight and capped allocation
  • Using clustering to spot near-duplicate strategies and stress-testing for overfitting
About 13 min read Updated July 13, 2026 For advanced traders and small managers

Key takeaways

  • Stacking good strategies is not diversification. Align returns on a common axis and read correlation, combined drawdown and simultaneous losses.
  • Measure correlation on common-calendar return series (such as daily), not on individual trades, and state the definition explicitly.
  • Low correlation in calm periods may not persist under stress. Correlation captures only linear co-movement.
  • Compare equal-capital, equal-risk, fixed-weight and capped allocation descriptively. Do not recommend a single optimum.
  • Use clustering to find near-duplicate strategies, and stress allocations across out-of-sample periods, costs and regimes.
Contents

This guide is written for advanced traders running multiple Pine strategies, markets or timeframes, and it explains how to evaluate a multi-strategy portfolio backtest from the perspective of running everything together rather than comparing standalone results. It moves through the direct answer, standardizing before combining, the meaning and definition of correlation, allocation methods, combined equity and portfolio drawdown, clustering, a volatility calculator, and how to apply stress. If you are still unsure how to read a single backtest, it helps to first grasp the complete TradingView backtesting workflow so this article sits in context.

The 30-second answer

When you evaluate a portfolio of strategies, simply lining up good ones is not diversification on its own. The benefit of diversification is decided by when and how much each strategy loses at the same time. So the first thing to do is align every strategy’s profit and loss to the same time axis, the same currency and the same starting capital, and build a return series on a common calendar.

On that foundation you then check the correlation between strategies, the combined drawdown after allocation, and the simultaneous losses during a sharp sell-off. Even when correlation looks low in normal conditions, it can spike during stress and pull several strategies down together. Below, using fictional educational data for three strategies (trend-following, mean-reversion and breakout), we look concretely at how to separate apparent diversification from real diversification.

Illustrative strategies used in this article (fictional educational data): Strategy A = trend-following (daily), Strategy B = mean-reversion (4-hour), Strategy C = breakout (daily). Assumed annualized volatility is A 20%, B 12%, C 24%, and standalone maximum drawdown is A −18%, B −11%, C −22%. These are all illustrative numbers, not real results or recommended values.

Standardize before combining

Before combining strategies, align the basis for comparison. Skip this step and the correlation and allocation that follow lose their meaning. At a minimum, standardize the following.

  • Period and time zone: Trim each strategy’s coverage to a common start and end, and unify the time zone. If the date basis is misaligned, you will under- or over-state simultaneous losses.
  • Currency: Convert profit and loss into a base currency. Adding raw amounts without converting lets exchange-rate moves leak into strategy correlations.
  • Starting capital: Assume the same starting capital and align on return rate rather than amounts, so differences in size do not distort each strategy’s contribution.
  • Trading costs: Unify spread, commission and slippage assumptions across strategies. Inconsistent assumptions push combined P&L away from reality. Modeling them is covered in cost sensitivity and stress testing.
  • Return frequency: Decide on the frequency used for correlation and combination (daily, weekly and so on) and apply it to every strategy. Mixed frequencies make correlation coefficients incomparable.
  • Missing data and overlapping positions: Decide how to treat gaps in the data and set a rule for aggregating positions when several strategies hold the same instrument in the same direction.

This standardization is unglamorous, but the reliability of portfolio testing is largely decided here. Proceed with a misaligned foundation and the correlation matrix and post-allocation drawdown you read later will reflect the roughness of your preprocessing rather than the nature of the strategies.

What correlation means and its limits

The correlation coefficient expresses, on a scale from −1 to +1, how much two strategies’ returns move together in the same direction. Closer to +1 means they rise and fall in step, closer to 0 means they are near-independent, and closer to −1 means they move oppositely. For diversification, the lower the correlation between combined strategies, the more the combined volatility and drawdown tend to fall below the sum of the individual parts.

But correlation has clear limits. First, it captures only linear co-movement. Non-linear links and structural dependence on the same driver are missed. Second, correlation depends on the period. Even when it is low in calm times, a sharp sell-off can push risk assets down together and drive many strategies’ correlations toward +1, a “correlation convergence.” In other words, low correlation in normal conditions is not guaranteed to hold during the very stress when you most need it. That is exactly why you should not judge diversification from a single correlation value; read it alongside simultaneous drawdowns and behavior by regime. For a view of the market backdrop, an external perspective such as the Macro Research Workbench can also help.

Correlation matrix for three strategies (color, numbers and pattern combined) A 3-by-3 matrix of daily-return correlations for strategies A, B and C. Strong correlation is shown by color depth plus numbers and a hatched pattern. A and C correlate at 0.62. All figures are fictional educational data. Correlation matrix (common-axis daily returns, fictional educational data) Strategy A Strategy B Strategy C Strategy A Strategy B Strategy C 1.00 0.15 0.62 0.15 1.00 0.08 0.62 0.08 1.00 Dark fill plus hatching = high correlation (0.6 or above). Numbers are shown too, so meaning is not color-only. A and C (both daily trend-family) correlate at 0.62 = effectively similar behavior.
Figure 1: Correlation matrix for three strategies. Alongside color depth, numbers and a hatched pattern mark the high correlation (A and C = 0.62). B is near-independent of A and C at 0.15 and 0.08. All figures are fictional educational data, not real correlations.

Which return series to correlate

When measuring correlation, the key implementation point is not to compute it trade-by-trade. Each strategy’s trades occur at different times and are held for different durations, so lining up per-trade profit and loss gives no shared time axis. Instead, convert everything into return series on a common calendar.

The implementation definition

This article defines correlation as follows. For each strategy, build a daily return series (that day’s percentage change in equity) over the common period. Days with no trade are set to a zero return so the series stays continuous. Then compute the Pearson correlation coefficient between two strategies’ daily return series. Frequency is unified at daily because mixed frequencies make correlations incomparable across strategies. If you want to match your operating granularity to weekly, align every strategy to weekly and recompute.

Under this definition, the correlation matrix in Figure 1 expresses “how much they moved together on the same day.” How to read standalone metrics such as trade count and win rate is covered in how to read backtest results, so understanding each strategy’s makeup before reading correlation keeps your interpretation stable.

Comparing capital allocation methods

Allocation is the step where you decide how much capital to assign to each strategy. Here we compare four representative methods descriptively. Each has trade-offs, and none is universally superior. This article does not recommend any particular allocation or a single optimum.

  • Equal-capital: Assign the same amount of capital to each strategy. Simple to implement, but a high-volatility strategy tends to dominate the portfolio’s risk.
  • Equal-risk (risk parity): Allocate inversely to each strategy’s assumed volatility, aiming to equalize risk contributions. It does not behave as intended if the volatility estimate is off.
  • Fixed-weight: Fix the ratios at the manager’s discretion (for example 50/30/20). The stance is clear, but the rationale can become subjective.
  • Capped: Set a ceiling on any one strategy’s weight (for example 40%) to limit concentration. Diversification is easier to preserve, but a mechanical cap can introduce inefficiency.

The table below applies each method to the three illustrative strategies, together with the combined annualized volatility and combined maximum drawdown as fictional educational data. Note that under equal-risk, low-volatility Strategy B (assumed 12%) receives a heavier weight and high-volatility Strategy C (assumed 24%) a lighter one.

Table 1: Weights and combined risk by allocation method (fictional educational data)
Allocation methodStrategy AStrategy BStrategy CCombined ann. vol.Combined max DD
Equal-capital33%33%34%13.0%−14.0%
Equal-risk29%48%23%11.0%−11.5%
Fixed-weight50%30%20%14.2%−16.2%
Capped (40%)40%40%20%12.4%−13.1%

The numbers in the table are fictional educational data meant to explain the allocation concepts. Combined annualized volatility and combined maximum drawdown change substantially if the correlation and volatility assumptions change. They do not show that any particular allocation is good or safe.

Combined equity and portfolio drawdown

Once weights are set, weight each strategy’s return series by its allocation and add them together to build the combined equity curve. From that curve, recompute the portfolio maximum drawdown. The important thing here is not to simply add up each strategy’s maximum drawdown. When correlation is low, one strategy holds up while another sinks, so the combined drawdown tends to be shallower than the sum of the individual ones. Conversely, when highly correlated strategies sink together, it can be deeper than expected.

Standalone equity for three strategies versus equal-capital combined equity Line chart overlaying the standalone equity curves of strategies A, B and C with the equal-capital combined portfolio curve. The combined curve varies more smoothly than the singles. Figures are fictional educational data. Standalone vs equal-capital combined (fictional educational data, index base 100) 160 120 100 Start Period end Strategy A Strategy B Strategy C Combined (equal-capital) Strategy A Strategy B Strategy C Equal-capital combined
Figure 2: Standalone equity for strategies A, B and C (thin lines) versus the equal-capital combined portfolio (thick line). The combined curve varies more smoothly than the singles, but that is the tendency when low correlation holds. Index base 100; all figures are fictional educational data.

The effect of combining is tested not only by calm-period smoothness but during simultaneous losses. The next figure decomposes each strategy’s monthly contribution during a sharp sell-off month (fictional educational data) and the combined profit and loss of the equal-capital portfolio. You can read the structure: daily trend-family strategies A and C swing negative together, while mean-reversion Strategy B moves slightly the other way and cushions the fall.

Profit contribution and simultaneous drawdown in a sell-off month Left is the stacked full-period P&L contribution (Strategy A 40%, B 35%, C 25%). Right shows a sell-off month’s monthly returns (A −8.0%, C −9.0%, B +1.5%) and the equal-capital combined −5.2%. Figures are fictional educational data. P&L contribution and simultaneous drawdown (fictional educational data) Full-period P&L contribution (equal-capital) A 40% B 35% C 25% Breakdown totals 100% Sell-off month monthly returns 0% A−8.0% C−9.0% B+1.5% Combined−5.2% A and C fall together B partly cushions
Figure 3: Left is the full-period P&L contribution (Strategy A 40%, Strategy B 35%, Strategy C 25%). Right is the sell-off month’s monthly returns, where Strategy A −8.0% and Strategy C −9.0% fall together, Strategy B +1.5% cushions part of it, and the equal-capital combined portfolio is −5.2%. Meaning is shown with labels and numbers, not color alone. All figures are fictional educational data.

Clustering to spot duplicate strategies

You can line up several strategies, but if they behave essentially the same, you have merely concentrated on one bet while believing you diversified. In the correlation matrix of Figure 1, strategies A and C correlated highly at 0.62. Both are daily trend-family strategies: they win together in the same trending phase and lose together at the same reversal. Grouping highly correlated strategies surfaces fewer clusters than the apparent count of strategies.

In this example, strategies A and C form one cluster (trend-family) and Strategy B forms another (mean-reversion). So even though it looks like “three strategies,” the number of independent sources of movement is effectively two. Clustering and similarity diagnostics help visualize such duplication numerically and check whether the allocation is skewed toward a particular cluster.

Apparent diversification versus effective diversification Left treats the three strategies as independent (apparent diversification). Right groups the highly correlated A and C into one cluster, leaving two effective clusters. Figures are fictional educational data. Apparent vs effective diversification (fictional educational data) Apparent: 3 independent strategies A B C “Feels” diversified = 3 lines Effective: grouped by correlation = 2 clusters A C Trend-family (corr 0.62) B Mean-reversion Independent sources = 2 in effect
Figure 4: Left is “apparent diversification,” treating the three strategies as independent; right is “effective diversification,” grouping strategies A and C (correlation 0.62) into one cluster. Even though it looks like three lines, the independent sources of movement are effectively two. All figures are fictional educational data.

Portfolio volatility calculator

How correlation changes combined risk can be felt intuitively with a simple two-strategy formula. Enter two strategies’ assumed annualized volatility, correlation coefficient and allocation weights into the calculator below and it displays a simplified portfolio volatility. The assumptions and formula stay visible at all times, and it does not output an optimal allocation. Values are computed entirely in your browser and never sent externally. If JavaScript is disabled, see the static worked example directly below.

Static worked example (JavaScript disabled): With Strategy 1 volatility 20%, Strategy 2 volatility 12%, correlation 0.15 and a 50%/50% allocation, portfolio volatility is σp = √(0.5²×20² + 0.5²×12² + 2×0.5×0.5×0.15×20×12) = √154 ≈ 12.4%. That is about 3.6 points lower than the simple weighted average (0.5×20 + 0.5×12 = 16.0%), and that gap is the diversification benefit from low correlation. If correlation were 1.0, σp = 16.0% with zero reduction; at correlation 0.0 it falls to about 11.7%. The higher the correlation, the smaller the diversification benefit.

Two-strategy portfolio volatility calculator

Dispersion of Strategy 1 returns
Dispersion of Strategy 2 returns
Strength of joint movement
The remainder is Strategy 2

Enter values above and press “Calculate volatility” to see the portfolio volatility and diversification benefit.

Portfolio assumed volatility σp
Simple weighted-average volatility (no diversification)
Diversification benefit (weighted average − σp)

This calculation is a conceptual simplified formula for showing how correlation affects risk; it does not indicate an optimal allocation or future risk. Real portfolios involve three or more strategies, time-varying correlation and non-linear joint risk that a single formula cannot fully capture. If the assumed volatility or correlation is wrong, the result changes too.

Stress-testing the historical optimum

An allocation that minimizes drawdown or maximizes Sharpe on past data is merely a result fitted to that period’s correlations and volatilities. Change the market regime and that allocation breaks down easily. So evaluate an allocation not as a single optimal point but as a distribution of outcomes when you shake the assumptions. How to spot overfitting itself is covered in how to detect backtest overfitting with parameter stability, and validation across time splits in walk-forward analysis and out-of-sample testing.

The angles for stressing an allocation are as follows.

  • Out-of-sample (OOS): Check the same allocation’s combined results over a period different from the one used to set it.
  • Correlation shift: Recompute combined drawdown using correlation restricted to sell-off phases rather than calm-period correlation.
  • Trading costs: Set spread, commission and slippage on the heavier side and see whether the ranking of contributions changes.
  • Constraints and caps: See how combined drawdown and contributions move once you cap any single strategy or cluster.
  • Rebalancing frequency: Vary the interval (monthly, quarterly and so on) and check that results are not overly sensitive to frequency.

The ordering of simultaneous losses and the impact of rare losing streaks are invisible in a single scenario. Combining Monte Carlo testing of risk of ruin, which randomly reshuffles losing streaks and sequence risk, with reading maximum drawdown for combined depth and recovery, lets you check the robustness of an allocation from several angles. A capital-allocation simulation is ultimately a distribution of outcomes and does not guarantee future returns or optimal management.

Practical checklist

  • Did you unify period, time zone, currency, starting capital, cost and return frequency across all strategies?
  • Did you compute correlation on common-axis return series with an explicit definition, not on individual trades?
  • Did you check not only calm-period correlation but also correlation and simultaneous drawdown during sell-offs?
  • Did you compare equal-capital, equal-risk, fixed-weight and capped descriptively rather than depending on a single optimum?
  • Did you compute combined maximum drawdown from the combined equity curve rather than summing the individual ones?
  • Did you group highly correlated strategies into clusters and separate the apparent count from the effective count?
  • Did you stress the allocation with OOS, correlation shift, cost, constraints and rebalancing frequency, and view results as a distribution?

Frequently asked questions

How do I combine multiple strategy backtests?
Align each strategy’s profit and loss on a common time axis, standardize them to the same starting capital, currency and return frequency, and then add them together over time according to your allocation weights. Rather than averaging standalone KPIs, line up return series on the same calendar period and time zone at a daily or weekly frequency, and only then compute the combined equity curve and combined drawdown. If you do not first resolve period mismatches, currency differences, inconsistent cost assumptions, missing data and overlapping positions, the combined figures will drift away from reality.
Which return series should I use for strategy correlation?
Use the correlation coefficient between return series aligned to a common time axis, for example daily or weekly returns, rather than individual trades. Trades occur at different times for each strategy, so measuring correlation trade-by-trade leaves no shared basis for comparison. This article adopts the definition of taking the Pearson correlation of daily returns over the same calendar period. Keep in mind that correlation captures only linear co-movement, and a calm-period value is not guaranteed to persist during stress.
Does low correlation guarantee diversification?
Low correlation is a necessary but not sufficient condition for diversification. Even when correlation is low in normal conditions, many strategies can lose together during a sharp sell-off as correlations spike. Because the correlation coefficient measures only linear relationships, it also misses non-linear joint risk and structural links where strategies react to the same driver. Do not rely on a low correlation number alone; read it together with simultaneous drawdowns and behavior during stress periods.
Can I compare strategies denominated in different currencies?
Yes, but you must unify the currency before combining them. Convert each strategy’s profit and loss into a base currency and align them to the same starting capital and return frequency before computing correlation or allocation. If you add raw amounts without converting, currency movements leak into the profit and loss and distort each strategy’s true correlation and contribution. Make your conversion-rate assumptions explicit, and decide whether you are intentionally carrying foreign-exchange risk into the portfolio.
What is the difference between equal-capital and equal-risk weighting?
Equal-capital weighting assigns the same amount of capital to each strategy; it is simple to implement, but a high-volatility strategy tends to dominate the portfolio’s risk. Equal-risk weighting, also called risk parity, allocates inversely to each strategy’s assumed volatility in an attempt to equalize risk contributions. There is no universal answer as to which is better, and neither behaves as intended if the underlying volatility estimates are wrong. Every allocation in this article is illustrative only.
Should I calculate maximum drawdown for the combined portfolio?
Yes. Rather than simply adding up each strategy’s maximum drawdown, recompute the maximum drawdown from the post-allocation combined equity curve. When correlation is low, the combined drawdown tends to be shallower than the sum of the individual ones, but when highly correlated strategies sink together it can be deeper than expected. It matters to read the combined drawdown, the recovery period and the contribution of simultaneous losses separately. Reading drawdown is covered in detail in a related article.
Can I reuse the historically optimal allocation as-is?
Avoid applying it directly to the future. An allocation that minimizes drawdown or maximizes Sharpe on past data is fitted to that period’s correlations and volatilities, and it tends to break down when the market regime changes. Evaluate an allocation not as a single optimal point but as a distribution of outcomes across out-of-sample periods, costs, regimes and rebalancing frequencies. Do not treat it as a guarantee of future returns or optimal management.
Can I compare multiple strategies on the free plan?
On the free plan you can load each strategy individually and review it one at a time with core KPIs, equity, drawdown, Monte Carlo and more. Cross-cutting analysis, such as combining multiple strategies into a portfolio, strategy correlation, capital-allocation simulation and clustering, is a higher-plan use case. A natural path is to confirm each strategy’s foundation for free first, then compare plans once you want to dig into the correlation and allocation of running them together.
Disclaimer: This article and the tool provide descriptive aggregation, diagnostics and visualization of the backtest data you load; they are educational and informational content, not investment advice, a buy or sell signal, a future price forecast or a guarantee of profit. All figures, charts and allocations shown are fictional educational data and do not represent real results or recommended allocations or parameters. The results of backtests and capital-allocation simulations do not guarantee future performance and change with assumptions, data, costs, correlation and market regime. Final decisions are your own responsibility. TradingView interface names and specifications may change, so please confirm the latest details on the official pages. SG Group does not claim any partnership with or endorsement by TradingView.