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Convexity Strategies

volatility-tradingLevel 3 — Advanced

Prerequisites

Options Market StructureVolatility ForecastingVolatility Trading

What It Is

Convexity strategies deliberately construct portfolios with positive asymmetry — where gains in favorable scenarios significantly exceed losses in adverse ones — through long options, tail hedges, or structural features in assets that produce optionality.

Correct Execution

  • Distinguish between embedded convexity (structural features in assets/strategies) and purchased convexity (explicitly buying options)
  • Focus tail hedges on protecting true catastrophes, not all drawdowns — expensive if you try to protect against every loss
  • Seek cheap convexity: options that are historically inexpensive AND have plausible scenarios for large moves
  • Accept that long convexity has negative carry in calm regimes — this cost must be weighed against the benefit in tail events
  • Trend-following strategies have embedded convexity: mechanically buying as prices rise and cutting as they fall creates a concave-to-losses, convex-to-gains profile

Progression Levels

Diagnostic Tree

Coaching Cues

  • "The opportunity for excess gains in markets comes from volatility, not from direction. If you know how to exploit volatility, you don't need to predict direction." — Brett Nelson, 2021-10-28
  • "Three regimes: base state (grinding calm), expansion (vol picks up), crisis (extreme). Your strategy has to be clear about which regime it profits in." — Brett Nelson, 2021-10-28
  • "Convexity in a CTA comes from the mechanical rule — you cut losers and let winners run. You're building a synthetic long option without paying premium." — Eric Crittenden, FWM S3E7

Common Errors

  1. Treating tail hedges as insurance against all drawdowns: Protecting against every 5-10% drawdown destroys expected returns → Reserve tail hedges for true catastrophe scenarios; accept small drawdowns as the cost of participation
  2. Conflating cheap implied vol with a good trade: Cheap IV is a necessary but not sufficient condition — you need a fundamental scenario for the move → Apply the "find reasons NOT to do the trade" test before buying cheap convexity
  3. Ignoring the base state drag when sizing long convexity: Long vol positions bleed in low-vol regimes; if sized too large they consume the portfolio's return budget → Size long convexity to a drag the portfolio can sustain over 3-5 years

Edges

🔑 Hidden Causal Lever

The Opportunity Is in the Vol Expansion Phase — Not the Crisis Phase

volatility-tradingconvexity-strategies →

Most convexity strategies are designed for the crisis phase (VIX > 40) and are sized appropriately for that terminal state. The actual highest risk/reward window is the expansion phase — when vol starts moving from 12-15 to 20-30, before the crisis manifests. In expansion, vol positions are cheaper (fear premium hasn't peaked), the move is directional and sustained, and the strategies can be sized larger because the risk of total loss on premium is lower. Most practitioners miss this phase entirely because they're waiting for the crisis to validate their positioning.

What most people do
Hold long vol positions sized for the crisis payoff, accept years of theta bleed, and wait for a VIX spike to 40+.
What the best do
Specifically design and size for the vol expansion phase; trigger increase in long vol exposure when vol starts rising from its base state, not after the crisis has begun; reduce long vol in crisis once the expansion has played out.
Why it's an edge: Most systematic vol strategies don't distinguish the three regimes (base state, expansion, crisis); they treat all non-crisis periods as drag. Understanding that the expansion phase is the high-Sharpe window concentrates sizing at the right time.
How to exploit: Define an expansion trigger as VIX crossing 1.5x its 90-day realized average (e.g., 12 average → trigger at 18). When triggered, increase long vol allocation by 50-100%. When VIX exceeds 35, reduce long vol (the expansion has likely already generated most of the profit); restore base sizing. Back-test this on VIX history from 2000 onward.
Cross-domain parallel
In sports betting, line movement early in the week — before the market is saturated with public betting — is the highest-information period. The expansion analogy: the most valuable signal occurs in the transition, not at the extreme.
Brett Nelson, "Convex to the Core," Corey Hoffstein podcast, 2021-10-28
💎 Elite-Only Behavior

"I Can't Find a Reason NOT to Buy" Is the Correct Decision Criterion for Cheap Convexity

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Standard options analysis asks: "Is there a reason TO buy this cheap vol?" The answer is almost always yes — historical IV comparison, correlation analysis, macro scenario. The correct framing inverts the burden of proof: "Can I find a reason NOT to buy this cheap vol?" The onus is on finding structural reasons why the market is correctly pricing the tail risk as low, not on constructing a scenario where the move could happen. If you cannot find a credible reason why the cheap vol is cheap, you should buy it.

What most people do
Evaluate cheap commodity or equity options by constructing plausible bullish scenarios; the scenario construction biases toward buying, which leads to consistent losses when the market's view of tail probability is correct.
What the best do
Start from the prior that cheap implied vol reflects market consensus; actively seek reasons the consensus is correct; only buy when you cannot find a structural reason the tail risk is as low as the market implies.
Why it's an edge: This inverted burden of proof is psychologically difficult — it requires accepting market efficiency as the starting prior and requires active effort to justify buying, rather than passive acceptance of "it looks cheap." Most traders fail this test.
How to exploit: For any cheap vol trade you're considering, list every structural reason the market might be correctly pricing it as cheap: seasonal quiet period? well-supplied commodity? high perceived central bank backstop? Only proceed if this list is short and unconvincing. Document the reasons-not-to-buy check as a required step before any convexity purchase.
Jeffrey Baird, "Commodity Convexity," FWM S3E6, 2021-04-10 — "the onus is to find reasons not to do the trade."
🔑 Hidden Causal Lever

Trend-Following's Convexity Is Free — But It Has a Speed Limit

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Trend-following strategies generate a synthetic long options payoff through their mechanical rule: cut losses and let winners run. This creates positive skew (small frequent losses, large occasional wins) without paying options premium. The embedded convexity is free in the sense that you get paid positive expected return for holding it. But the convexity is not available at all speeds — it requires the underlying trend to develop over weeks to months. For sudden crashes (V-shaped selloff or flash crash), the trend system cannot build a position fast enough and the "free convexity" doesn't fire. This is a structural limitation that must be explicitly acknowledged.

What most people do
Describe managed futures as a crisis hedge; promise crisis alpha to investors without qualifying the speed requirement.
What the best do
Position trend-following as "embedded convexity at the price of a positive-expected-return investment" — not as insurance. Acknowledge the scenario where it doesn't work (sudden crashes) and explicitly pair it with purchased tail hedges for true crisis protection.
Why it's an edge: Most trend-following managers and allocators misrepresent the nature of the convexity. Understanding the speed constraint lets you design the right supplement (purchased options for intraday/week crashes) rather than blaming the trend strategy for failing to protect against something it was never designed to protect.
How to exploit: Catalog the historical scenarios where trend-following did NOT provide crisis protection: Flash Crash May 2010, sudden COVID spike in late February 2020 (before trend systems could position), 2015 August selloff. Use these as inputs to size a purchased tail hedge that specifically covers the "too fast for trend" scenario. The combination — trend for sustained crises, options for sudden crashes — provides genuine all-weather protection.
Cross-domain parallel
In algorithmic trading, mean-reversion strategies fail during trend regimes and trend strategies fail during mean-reversion regimes. No single strategy architecture covers all market conditions — you must design the combination explicitly.
Eric Crittenden, "All-Weather Portfolios," FWM S3E7, 2021-04-10 — "I can create a scenario where managed futures doesn't make a bunch of money when equities go down."

Sources

  • Brett Nelson, "Convex to the Core with Certeza," Corey Hoffstein podcast, 2021-10-28 — three-regime volatility framework; tail hedge sizing; exploiting volatility change vs level
  • Jeffrey Baird, "Commodity Convexity," Flirting with Models S3E6, 2021-04-10 — cheap convexity identification in commodities; negative reason criterion for buying cheap vol
  • Eric Crittenden, "All-Weather Portfolios with Trend Following," Flirting with Models S3E7, 2021-04-10 — embedded convexity in trend strategies; crisis alpha limitations