You trade with the trend, but the market reverses, eating into profits. "Buy the dip, sell the top" — a mantra that in practice leads to losses. We build AI models that don't predict the future, but calculate the probability of a reversal at a specific moment, relying on technical, sentiment, and positional data. Unlike lagging indicators, our composite approach combines an HMM regime detector with an ensemble of features, providing leading signals.
Problems with Reversals and Their Solution
Reversals are rare, nonlinear events. Classic indicators like RSI and MACD lag: the crossover happens after the price has already bounced. We address this with divergence detection: price updates an extreme, but RSI doesn't. The signal leads the lag by 2–3 candles. Most "reversals" are false moves. We filter them with HMM: positions are opened only in ranging or volatile regimes. Reversals are identified via ZigZag with a minimum move of 5% for swing high/low labels.
How HMM Helps Filter Noise
The Hidden Markov Model classifies the current market state into three regimes: trend, flat, volatile. We use features: 5-day returns, volatility (ATR/close), volume relative to SMA20. In trend (regime 0), we apply momentum strategies; in regimes 1 and 2, reversal. Detector code:
from hmmlearn import hmm
import numpy as np
features = np.column_stack([returns_5d, atr20_close, volume_sma20_ratio])
model = hmm.GaussianHMM(n_components=3, covariance_type='full', n_iter=100)
model.fit(features)
regimes = model.predict(features)
# 0: trending, 1: ranging, 2: volatile/crisis
Composite Reversal Score
A single indicator is unreliable. We assemble an ensemble of 10 diverse features: distance from SMA200, RSI 14, 20d z-score, price/RSI divergence, volume/price divergence, put/call ratio, VIX, short interest, higher high, distance to nearest support/resistance level.
The algorithm is a Random Forest Classifier (100 trees, depth 7). The target is a reversal within 5 days based on ZigZag. It outputs a probability — the reversal score. We enter when score > 0.65. Position size is proportional to score, from 1% to 2.5% of the portfolio. Stop-loss at the last swing extreme, take-profit at the next significant level, maximum holding 10 days.
What the Composite Score Delivers
A single indicator gives ~40% accuracy. The composite of 10 features boosts accuracy to 53% out-of-sample — a 30% improvement. With R:R = 1:2, even a 47% win rate yields positive mathematical expectation. Profit factor 1.7 vs 2.2 for momentum, but drawdowns are shorter. Investment in such a model pays off by reducing losses from false entries; backtesting shows an average 30% time savings.
Backtesting Evaluation
| Metric |
Target |
| Win Rate |
45-55% |
| Profit Factor |
> 1.5 |
| Max Drawdown |
< 15% |
| Sharpe (after TC) |
> 0.8 |
Strategy comparison:
| Strategy |
Win Rate |
Profit Factor |
Max DD |
| Reversal composite |
47–53% |
1.7 |
11% |
| Momentum trend |
55–60% |
2.2 |
18% |
What's Included
- Liquidity and historical pattern analysis
- Development of HMM regime detector + composite score
- Backtesting with commissions and slippage
- Documentation, code, API for integration
- Team training (2 days)
- Support for 1 month after delivery
Process and Partnership Format
Process:
- Analytics — data collection, instrument specifics, ZigZag parameter and reversal window determination.
- Design — feature selection, ensemble architecture, HMM tuning.
- Implementation — Python code, trading terminal integration via REST API.
- Testing — out-of-sample and walk-forward validation.
- Deployment — Docker containerization, scheduling, metric monitoring.
Example Model Configuration for S&P 500
- Timeframe: daily
- Features: distance from SMA200, RSI14, divergence, VIX, put/call ratio
- HMM: 3 states, full covariance
- RF: 100 trees, max_depth=7, min_samples_leaf=50
- Score threshold: 0.65
- Position sizing: linear from 1% (score=0.65) to 2.5% (score=0.85)
- Stop-loss: last swing high/low
- Take-profit: next support/resistance level
Timeline and Budget. Development takes from 4 weeks (basic detector) to 4 months (full system). Cost is calculated individually based on data volume, number of instruments, and required architecture. Average time savings on backtesting amount to 30% — investment pays off through improved metrics. According to research, the composite approach increases Sharpe ratio by 0.3–0.5.
Company experience: 7+ years in ML for finance, 50+ projects in algorithmic trading. We use industrial MLOps (MLflow, Kubeflow). We guarantee metrology: model calibration and validation.
Contact us to discuss your task — we will analyze your data and propose an architecture. Order development today and get a consultation.
When does a time series forecasting model fail in production?
The CFO requests a quarterly sales forecast. An analyst builds SARIMA on three years of data, achieves MAPE 8.3% on the test set, and deploys. Two months later, the metric in production jumps to 23%. The root cause: the model was trained on pre‑COVID data, tested on a stable period, but production hit a promotion and supply chain disruption. Data leakage plus distribution shift—perfect notebook numbers, a broken forecast in reality. We have seen this pattern dozens of times across retail, fintech, and IoT. Our team has delivered more than 50 forecasting projects over 5+ years.
Incorrect cross-validation. Standard train_test_split for time series creates data leakage: the model sees future values during training. The correct approach is TimeSeriesSplit or walk‑forward validation with an expanding window.
Multiple seasonality. Hourly electricity consumption has three seasonalities: daily (24h), weekly (168h), yearly (8760h). SARIMA handles only one. Prophet can handle multiple but scales poorly to thousands of series.
Missing values and anomalies. A missing sensor reading is information (the sensor turned off), not NaN. Linear interpolation destroys this signal. Proper handling depends on the missingness mechanism.
Cold start. A new SKU in a 50,000‑item assortment has no history, yet a forecast is needed. Standard approaches fail; cross‑learning or feature‑based methods are required.
Why is model selection critical for your data?
Prophet (Meta) – a solid start for business data with clear seasonality and holidays. Fast setup, interpretable, built‑in outlier detection. Fails on irregular patterns and does not scale beyond ~10k series without parallelization.
Gradient boosting on features (LightGBM, XGBoost) – often underestimated. Engineer lags (t‑1, t‑7, t‑28), rolling means, day‑of‑week, holidays. The model trains on all series simultaneously, solving cold start via transfer learning. MAPE in retail often beats neural nets with proper feature engineering.
TFT (Temporal Fusion Transformer) – a transformer designed for interpretable forecasting with covariates. Built‑in variable selection, temporal attention, quantile outputs. Available in pytorch‑forecasting. Requires ~10,000+ records per series for stable training.
PatchTST – splits the series into patches (like ViT for images), capturing local patterns better than classic transformers. Excellent for long‑horizon forecasting (96–720 steps ahead).
N‑HiTS, N‑BEATS – attention‑free neural architectures, faster than TFT, competitive accuracy. N‑BEATS won the M4/M5 benchmarks for tasks without covariates.
| Method |
Covariates |
Scale (series) |
Interpretability |
Complexity |
| Prophet |
Yes (regressors) |
Up to 10k |
High |
Low |
| LightGBM + features |
Yes |
100k+ |
Medium |
Medium |
| TFT |
Yes |
1k–100k |
High |
High |
| PatchTST |
No/limited |
Any |
Low |
Medium |
| N‑HiTS |
No |
Any |
Low |
Low |
How do we deploy TFT in production?
A typical pipeline via pytorch‑forecasting:
training = TimeSeriesDataSet(
data,
time_idx="time_idx",
target="sales",
group_ids=["store", "sku"],
min_encoder_length=max_encoder_length // 2,
max_encoder_length=max_encoder_length, # 120 days
min_prediction_length=1,
max_prediction_length=max_prediction_length, # 28 days
static_categoricals=["store_type", "category"],
time_varying_known_reals=["price", "promo_flag"],
time_varying_unknown_reals=["sales"],
target_normalizer=GroupNormalizer(groups=["store", "sku"], transformation="softplus"),
)
A common mistake: the default target_normalizer (StandardScaler) breaks predictions for series with zero values (no sales on weekends). GroupNormalizer with transformation="softplus" is the correct choice for count data.
Case study: retail demand forecasting
A chain of 120 stores, 8,000 SKUs, 28‑day forecast horizon. The original system: SARIMA per series, MAPE 18.4%, retraining cycle – 6 hours. We replaced it with TFT on PyTorch + pytorch‑forecasting: a single model for all series, MAPE 11.2%, retraining – 40 minutes on an A10G. Feature importance via variable selection revealed that day_before_holiday influences more than the holiday date itself. Annual savings on inference alone exceeded $50,000.
Step‑by‑step configuration
-
Data collection and preparation. Handle missing values (mark NaN, interpolate only for technical failures), aggregate to required frequency, engineer covariates (holidays, promotions, prices).
-
Create
TimeSeriesDataSet. Set group_ids (store + SKU), time index, forecast horizon. Choose target_normalizer based on target distribution.
-
Train a baseline. Prophet or LightGBM first – to understand complexity.
-
Train TFT. Use
TemporalFusionTransformer with loss=QuantileLoss(), tune learning rate and hidden layer sizes.
-
Validate and interpret. Walk‑forward test, analyze variable selection, build attention heatmaps.
How to properly evaluate forecast quality?
RMSE alone is misleading – it over‑penalizes large values. Our standard set:
-
MAPE – interpretable, unstable near zero.
-
sMAPE – symmetric, avoids division by small numbers.
-
MASE (Mean Absolute Scaled Error) – normalized relative to a naive seasonal forecast, ideal for comparing series of different scales.
-
Pinball loss – for probabilistic forecasting, inventory management.
| Metric |
When to use |
Drawback |
| MAPE |
Business reporting, series without zeros |
Unstable for small values |
| sMAPE |
Model comparison |
Asymmetric interpretation |
| MASE |
Multi‑scale series, benchmarks |
Needs seasonal naive baseline |
| Pinball loss |
Probabilistic models |
Multiple values for different quantiles |
We guarantee a model card with these metrics on the validation set and walk‑forward results on at least 6 months of history.
What deliverables do you receive?
- Documentation of chosen architecture and hyperparameter rationale.
- Reproducible training and inference pipeline (Docker + CI/CD + Airflow/Prefect).
- Committed code with unit tests for key components.
- Team training: retraining, output interpretation, deployment of new versions.
- 3 months of post‑delivery support (consultations, bug fixes, fine‑tuning).
The model is deployed via FastAPI or Triton Inference Server. Retraining is scheduled (e.g., weekly) via Airflow with drift validation and automatic rollback if metrics deteriorate.
Process and timeline
We start with EDA: visualization, ADF test, STL decomposition, analysis of missing values and outliers. This takes 2–3 days but often reveals systemic data issues that block forecasting. Then we build a baseline (naive seasonal, Prophet), engineer features for LightGBM, and select a neural architecture if needed. Walk‑forward validation with a realistic horizon. Deployment via API with automatic retraining scheduled via Airflow or Prefect.
Timeline: MVP forecast on one data type – 3–6 weeks. Hierarchical forecasting system with automation – 2–5 months. Cost is calculated individually based on data volume, number of series, and required accuracy.
Our team consists of certified ML engineers (AWS ML Specialty, GCP Professional ML Engineer) with 5+ years on the market and over 50 completed forecasting projects. Contact us for a free analysis of your data – we will assess the task and provide initial recommendations within 1–2 days. Request a consultation to ensure your forecasts work in production, not just in a notebook.