hmmm… Looking more into it.

1. Data Cleaning and Preprocessing

a. Handle Missing Data

• Identify gaps in OHLC data using visualization or null checks.

• Techniques to fill gaps:

• Forward/Backward Fill: Fill with the nearest available data.

• Interpolation: Linear or spline methods for smoother filling.

• Drop Rows: If missing values are minimal and non-critical.

• Research:

“A Comparison of Techniques for Handling Missing Data in Time Series” (Journal of Time Series Analysis).

b. Adjust for Corporate Actions

• Adjust prices for stock splits, dividends, and rights issues.

• Use adjustment factors from reliable sources like Bloomberg or Yahoo Finance.

c. Outlier Detection

• Identify price or volume spikes due to anomalies (e.g., data errors).

• Methods:

• Z-Score/Standard Deviation Filtering.

• Advanced: Isolation Forest or DBSCAN for density-based outlier detection.

d. Standardization

• Normalize features like price, returns, and volume to comparable scales.

• Standard Scaler (Z-Score) or Min-Max scaling based on clustering needs.

2. Feature Engineering

a. Basic Features

Returns: Daily, weekly, and cumulative.

Volatility: Standard deviation, Average True Range (ATR).

Moving Averages: Simple, Exponential, and Weighted.

Momentum Indicators: RSI, MACD, Stochastic Oscillators.

• Research:

“The Use of Moving Averages in Technical Analysis” (Technical Analysis of Stocks & Commodities Journal).

b. Risk-Adjusted Metrics

Sharpe Ratio: Reward-to-risk ratio.

Sortino Ratio: Penalizes downside risk more heavily.

• Research:

“Sharpe and Beyond: An Empirical Analysis of Risk-Adjusted Performance Metrics” (Financial Analysts Journal).

c. Market and Sector Features

• Compute beta values to market indices.

• Use sector/industry classification for grouping.

d. Derived Features

Volume Indicators: On-Balance Volume, Chaikin Money Flow.

Trend Strength: Average Directional Index (ADX).

e. Dimensionality Reduction for Clustering

• Use Principal Component Analysis (PCA) to reduce feature redundancy.

3. Pattern and Correlation Analysis

a. Distributions

• Visualize distributions of returns, volatility, etc. using histograms and KDE plots.

• Research:

“Modeling Financial Returns: Insights from Fat-Tail Distributions” (Quantitative Finance).

b. Correlations

• Correlation Matrices: Visualize Pearson/Spearman correlations.

• Rolling Correlations: Capture time-varying relationships.

• Tools: Use heatmaps with Seaborn or D3.js for interactive exploration.

• Research:

“Dynamic Correlation Models for Financial Time Series” (Journal of Econometrics).

c. Pattern Detection

• Identify recurring patterns using Time Series Motif Discovery.

• Research:

“Efficient Discovery of Frequent Patterns in Time Series Data” (Knowledge and Information Systems).

d. Seasonality and Trends

• Use STL decomposition (Seasonal and Trend decomposition using LOESS).

• Research:

“Detecting and Understanding Seasonal Patterns in Stock Returns” (Journal of Finance).

e. Anomaly Detection

• Methods:

• Z-Score, Bollinger Bands for deviations.

• Advanced: Autoencoders for unsupervised anomaly detection.

• Research:

“Anomaly Detection in Financial Time Series Using Deep Learning Models” (arXiv).

4. Resources for Exploration

Quantitative Finance Stack Exchange

Threads:

“Best Practices for Feature Engineering in Quant Finance”.

“Time Series Preprocessing for Financial Models”.

• Ask and explore discussions on advanced preprocessing.

Research Repositories

arXiv: Search for papers on “OHLC preprocessing” or “feature extraction in finance.”

SSRN: Database of finance-related academic papers.

Tools

• Python Libraries:

• tsfresh and pmdarima: For automated feature extraction.

• finta: For technical indicators.

• pyod: For anomaly detection.

Would you like me to find specific research papers or expand on any of these techniques?