Backtesting praktyka — framework krok po kroku

Pełny 7-step framework: Step 1: Define strategy rules. Każda zasada specific + objective: entry signal (e.g. "RSI < 30 + price above 200 EMA"), exit signal, SL placement (e.g. "1.5× ATR below entry"), TP placement, position sizing rules. NIE subjective ("look feels right"). Code-able rules. Step 2: Select historical data. Minimum 5 lat dla credibility. 10+ lat ideal. Multiple timeframes if needed. Use real broker data ideally (Tickstory MT4 historical, Dukascopy free). Step 3: Choose tool. MT4 Strategy Tester: free, beginner-friendly, MT4 historical data. TradingView Pine Script: easy syntax, visual backtest report. Python backtrader: free, programmatic, full control, advanced analytics. NinjaTrader/TradeStation: pro platforms with walk-forward built-in. Step 4: Run backtest. Minimum 100 trades dla statistical significance. Common: 500-1000 trades on 5 years M15 data. Settings: starting capital, position sizing, broker fees, slippage assumption. Step 5: Analyze metrics. WR %, expectancy €, Sharpe, max DD, profit factor (gross profit / gross loss), avg win / avg loss, R-multiple distribution. Step 6: Walk-forward analysis. Anti-curve-fit validation. IS optimization, OS test. Step 7: Forward test demo. 3-6 mies. real-time market conditions. Validates backtest assumptions. Total time investment: 40-100 hours dla quality strategy. NIE shortcut.

MT4 Strategy Tester = beginner-friendly tool. Steps: (1) Open MT4. (2) View → Strategy Tester (Ctrl+R). (3) Select Expert Advisor (EA) coding strategy in MQL4 lub use existing free EA. (4) Select symbol (EUR/USD). (5) Select model (Every tick most accurate, Control points faster, Open prices fastest). (6) Time period (start - end dates). (7) Spread (current OR custom). (8) Optimization (off dla initial backtest, on dla parameter sweep). (9) Start. Results show: graph equity curve, statistics tab (total trades, WR, profit factor, expected payoff), report tab (detailed trade list). Coding EA basics: MQL4 syntax. Free EA templates dostępne online. Example simple RSI EA: 50 lines of code. Beginners use existing then modify. Historical data download: Tools → History Center (F2). Download EUR/USD M15, M30, H1, H4 data 5+ years. MT4 default data sometimes incomplete — supplement with Tickstory ($30 download) lub Dukascopy free. Limitations MT4: only EAs (no manual strategy backtest), MT4 historical data quality varies, slow dla large datasets. Speed tip: "Open prices" model 10× faster than "Every tick", but less accurate. Use Open dla initial parameter sweep, Every tick dla final validation. Backtest report: save HTML report dla future reference. Compare backtests over time.

TradingView Pine Script = popular dla retail. Pros: easy syntax (close JavaScript), visual results, free tier sufficient many cases, Bar Replay manual backtest possible. Cons: limited data history (free 5k bars, paid 20k bars), TradingView fees commission less granular than MT4, NIE walk-forward built-in. Steps: (1) Open chart EUR/USD. (2) Pine Editor bottom panel. (3) Click "Indicators" → "New Strategy". (4) Code strategy in Pine. (5) Apply to chart. (6) Strategy Tester tab pojawi się. (7) View Performance Summary + List of Trades. Example Pine Script breakout strategy: 30 lines of code. //@version=5 strategy("Breakout Strategy"). Define entry: ta.crossover(close, ta.highest(close, 20)). Exit: ta.crossunder(close, ta.lowest(close, 10)). SL: strategy.exit("exit", "long", stop=close * 0.98). 5 min coding simple strategies. Free vs paid: Free tier = 5,000 historical bars (M15 = 50+ days, Daily = 13+ years). Paid Pro ($14.95/mies.) = 10,000 bars. Pro+ ($29.95) = 20,000 bars. Premium ($59.95) = unlimited. Year 1 = free OK. Bar Replay manual backtest: TradingView tool replay historical data. Step through bars, simulate trade decisions manually. Best dla discretionary traders backtesting visual setups. NIE quantitative metrics, ale realistic experience.

5 main backtest pitfalls + solutions: (1) Curve-fitting (over-optimization): testing 100+ parameter combinations finds spurious "best". Backtest 80% WR → live 45% WR. Solution: walk-forward analysis, OS validation, parameter stability check. WFE > 50% required. (2) Lookahead bias: accidentally using future data. E.g. SL based on tomorrow's high. Subtle, hard to detect. Solution: code review carefully, separate IS/OS strictly, NIE use information NOT available at trade time. (3) Survivorship bias: backtesting only currently-existing pairs. EUR/USD always exists. But would strategy work on currencies discontinued? Solution: backtest on stable mainstream pairs only OR include delisted historical data. (4) Ignoring spread + slippage: backtest assumes perfect fills at quoted prices. Reality: spread 0.5-2 pips + slippage 0.5-3 pips. EUR/USD scalping 5 pips target = spread costs eat 30-50% profit. Solution: include realistic spread (1-2 pips) + slippage (0.5-1 pip) w backtest. Conservative > optimistic. (5) Insufficient data: 6 months backtest = noise. Strategy worked one regime. Solution: minimum 5 years, 10+ years ideal. Multiple market regimes (low vol, high vol, trending, ranging, crisis). Realistic expectation: backtest performance 30-50% better than live typically. Plan around backtest × 0.5 = live expected. Pleasant surprises rare.