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We put popular trading ideas through the data, and publish what works, what fails, and what only looked good on the right chart.

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45 articles · 23 under the research standard · Every result published, including the ones that failed

Latest issue

#145·Backtesting & Validation

S&P 500 Opening Gaps: Direction Is Noise, Size Is the Signal

Oct 8, 2026 · 11 min read

I tested all 8,397 S&P 500 opening gaps since 1993 to find out whether a gap up or a gap down tells you anything about the next few days. It tells you almost nothing: over five days, up-gaps drift +0.206% and down-gaps +0.194%. Direction is close to noise, and size is what carries the signal. Gaps over 2% average 0.368% the next day. By direction, down-gaps fill 98% of the time and up-gaps 94%, usually the same day.

Read the study→
  • #144·Market Behavior & Concepts

    S&P 500 Big Range Days: A Big Day Predicts Volatility, Not Direction

    Oct 1, 2026 · 11 min read

    "Big range day" means three different things depending on whether you measure in points, percent of price, or ATR, and the rulers disagree about which days even count: 549 of the 635 six-point days landed in the 2020s, as SPY went from $44.34 to $741.75.

  • #143·Strategies, Backtested

    RSI vs Stochastic vs Williams %R: 33,792 Backtests

    Sep 24, 2026 · 12 min read

    33,792 backtests across RSI, Stochastic and Williams %R on four index ETFs: the setup matters more than the indicator. 89.7% of long-side variants made money against 8.8% of short-side, and buying dips beat chasing breakouts 55.7% to 42.9%.

  • #142·Strategies, Backtested

    The Better-RSI Showdown: We Tested 4 RSI Upgrades on SPY, QQQ, IWM, and DIA

    Sep 10, 2026 · 10 min read

    1,856 backtests across four RSI families on SPY, QQQ, IWM and DIA: Connors RSI and Z-Score RSI modestly beat plain RSI on median risk-adjusted return, Laguerre RSI was the worst of the four despite its lag-free marketing, and the simplified three-condition Triple RSI tested here does not reproduce the popular win-rate claim.

  • #141·Strategies, Backtested

    I Backtested ICT / Smart Money Concepts — What Survives

    Sep 3, 2026 · 10 min read

    The four core ICT / Smart Money Concepts entries — order blocks, fair value gaps, liquidity sweeps and Optimal Trade Entry — codified into mechanical rules and run against three textbook entries and a coin flip across four markets. None showed a statistically significant 5- or 10-day forward-return edge on SPY.

  • #140·Tools, Software & Tech Stack

    Can AI Build a Profitable Trading Strategy? I Backtested 5 LLM-Generated Rules on SPY to Find Out

    Aug 22, 2026 · 11 min read

    Two experiments on SPY: a 2,304-variant optimizer sweep standing in for what AI does when it hunts for "the best strategy," and 5 AI-generated rules implemented verbatim. The optimizer's top-25 risk-adjusted score collapsed 85% out-of-sample, and 0 of 2,068 eligible strategies beat buy-and-hold.

  • #139·Backtesting & Validation

    Coin Flip Trading: What Randomness Tells Us About Market Bias

    Oct 11, 2025 · 5 min read

    Coin flip backtests show hidden market tendencies in ES, NG, and AD.

  • #138·Portfolio & Risk

    Dollar Cost Averaging vs Moving Averages: Why Risk Management Wins Every Time

    Aug 17, 2025 · 5 min read

    Dollar Cost Averaging leaves you exposed to big losses. Learn how moving averages and Tactical Asset Allocation deliver smoother returns and stronger downside protection.

  • #137·Strategies, Backtested

    Keltner Channels vs Bollinger Bands: 116,640 Backtests (and the Third Band I Built)

    Aug 2, 2025 · 12 min read

    116,640 backtests put Bollinger Bands, Keltner Channels and Casey Bands through one identical harness. Measured the same way on both, the band you pick moves the share of profitable long variants by 2.8 percentage points and the side you trade moves it by 90.4. At each family's most durable SPY setting, paying 0.05% a side drops Bollinger below buy-and-hold on MAR while the other two stay ahead.

  • #136·Strategies, Backtested

    Larry Connors R3 Strategy — Rebuilt for Index Futures (With a Smarter Filter)

    Jul 26, 2025 · 4 min read

    Larry Connors’ R3 strategy still works, if you update it. Discover how volatility filters and index futures give more trades and a better edge.

  • #134·Strategies, Backtested

    Same Breakout Strategy, Different Results: Nasdaq vs. SP500 vs. Dow

    Jun 20, 2025 · 3 min read

    Compare how the same breakout strategy performs on Nasdaq, S&P 500, and Dow. The results may surprise you.

  • #133·Strategies, Backtested

    📚 How to Build Profitable Strategies with the CCI Indicator

    Jun 13, 2025 · 4 min read

    Learn how to build short-side CCI strategies that actually work, tested on British Pound futures with real strategy results.

  • #132·Strategies, Backtested

    Donchian Channel Strategy: I Backtested '40 In, 20 Out' 1,188 Ways on 33 Years of SPY

    Jun 6, 2025 · 8 min read

    The classic 40-in/20-out channel breakout, re-tested 1,188 ways on 33.4 years of SPY: long-only still made 105.5% frictionless — but the famous 20-day-low exit lost to a plain 20-bar time exit, every unfiltered short entry length lost money under the channel-20 cover and three of the six drew down past 100%, and the edge has decayed every decade.

  • #131·Tools, Software & Tech Stack

    StrategyQuant X Review: The No-Code Way to Build Trading Strategies

    May 30, 2025 · 15 min read

    I have run StrategyQuant X on an Ultimate licence since 2019, I am a paid affiliate, and my course is built around it — all stated up front. Here is the verified 2026 pricing ($1,290 Starter, $1,490 Professional, $2,900 Ultimate), the edition gate that decides the purchase, what Build 144 changed, and who should not buy it.

  • #130·Strategies, Backtested

    Cumulative RSI Strategy: A Smarter Twist on RSI(2) for S&P 500

    May 23, 2025 · 4 min read

    Discover how Cumulative RSI improves over RSI(2) with smoother signals and real-world profits on the S&P 500

  • #129·Strategies, Backtested

    Range Expansion Index (REI): The Indicator Traders Are Missing Out On

    May 16, 2025 · 3 min read

    Discover the Range Expansion Index (REI), a powerful RSI alternative proven to enhance trading signals on major indexes.

Page 1 of 3

First←123→Last
▸ Browse all 45 articles
  • S&P 500 Opening Gaps: Direction Is Noise, Size Is the Signal
  • S&P 500 Big Range Days: A Big Day Predicts Volatility, Not Direction
  • RSI vs Stochastic vs Williams %R: 33,792 Backtests
  • The Better-RSI Showdown: We Tested 4 RSI Upgrades on SPY, QQQ, IWM, and DIA
  • I Backtested ICT / Smart Money Concepts — What Survives
  • Can AI Build a Profitable Trading Strategy? I Backtested 5 LLM-Generated Rules on SPY to Find Out
  • Coin Flip Trading: What Randomness Tells Us About Market Bias
  • Dollar Cost Averaging vs Moving Averages: Why Risk Management Wins Every Time
  • Keltner Channels vs Bollinger Bands: 116,640 Backtests (and the Third Band I Built)
  • Larry Connors R3 Strategy — Rebuilt for Index Futures (With a Smarter Filter)
  • Same Breakout Strategy, Different Results: Nasdaq vs. SP500 vs. Dow
  • 📚 How to Build Profitable Strategies with the CCI Indicator
  • Donchian Channel Strategy: I Backtested '40 In, 20 Out' 1,188 Ways on 33 Years of SPY
  • StrategyQuant X Review: The No-Code Way to Build Trading Strategies
  • Cumulative RSI Strategy: A Smarter Twist on RSI(2) for S&P 500
  • Range Expansion Index (REI): The Indicator Traders Are Missing Out On
  • The #1 Lesson Traders Learn Too Late: No Single System Will Save You
  • Weekly Mean Reversion Strategy: 22,680 Backtests Say the Rule Works and the Volume Filter Does Not
  • Volume Oscillator: A Beginner’s Secret to Smarter Trades
  • What Is the VIX Index? A Beginner’s Guide to Market Volatility
  • How the IBS Strategy Made $45K in 2024 — Even in a Down Market!
  • Ultimate C%: A Smarter Mean Reversion Indicator for Beginner Traders
  • Robustness Testing: Why Most Traders Fail, and What 36,252 Backtests Say Actually Works
  • Z-Score Mean Reversion Strategy: 2,400 Backtests on Futures and SPY, and the 74% Win Rate Is a Trap
  • AI Trading Strategy Development: The Exact Prompts, Step by Step
  • Tactical Asset Allocation (TAA): A Smarter Way to Invest Without Market Predictions
  • Mastering Market Regimes: When to Trade and When to Stay Out
  • Natural Talent vs. Skill in Trading: Why Anyone Can Learn to Trade Profitably
  • Water Fasting for Traders: How to Boost Focus & Clear Brain Fog
  • RSI Deep Dive: How to Trade the S&P 500 Like a Pro with Mean Reversion
  • CaseyC% Oscillator: A Smarter Mean Reversion Strategy for SP500 Traders
  • Market Edge: Why Markets Are Not Random (With Data to Prove It!
  • Cyclic RSI: The Indicator That Redefines Market Timing
  • OBV MACD vs. Traditional MACD: 9,216 Backtests Say You Are Asking the Wrong Question
  • Do Volume and Volatility Filters Actually Improve RSI(2)? 15,552 Backtests Say Mostly No
  • Ray Dalio's Holy Grail of Investing, Tested: Four Asset Classes Beat Nine Funds
  • ADX Indicator Tested: 8,370 Days Say It Measures Size, Not Direction
  • Larry Connors Double 7 Strategy: The Exact Rules, Tested 4,320 Ways on 33 Years of S&P 500 Data
  • Awesome Oscillator Tested: 14,000 Backtests, and 5/34 Ranks 28th
  • Investing Doesn’t Have to Be Hard: The Bucket System Simplified 🪣
  • 13 Best Candlestick Patterns for Trading the USDJPY Forex Pair 📊: Featuring Two Proven Strategies!
  • S&P 500 Drawdowns Since 1871: Every Decline, How Long They Lasted, and What Actually Recovered
  • Monte Carlo for Traders: I Checked Whether the Simulation Was Right. It Wasn't.
  • Toby Crabel's Thrust Patterns: 17,424 Backtests. Random Entries Matched the Up Thrust on Half the Markets
  • VIX Trading Strategy Tested: 2,520 Backtests Say the Roll Pays, Not the Timing

StatOasis is calm, evidence-based algorithmic-trading education, founded by Ali Casey. Ali builds systematic trading strategies and teaches the workflow behind them: research, build, test, combine, deploy. He writes the Overfit newsletter, published since 2024, and runs the Algo Trading Masterclass.

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