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Contents

  • 1 Get Started
  • 2 Interactive Charts
  • 3 Browse by Topic
  • 4 Clear Derivations
  • 5 Code Examples
  • 6 How to Use This Site

Sophos Alpha Research

Quantitative Finance Education & Research

Educational resources for understanding quantitative finance — from foundational concepts to advanced trading strategies.

  • Get Started — Jump into 9 core topics from foundations to machine learning
  • Interactive Charts — Explore 3D visualizations with zoom, rotate, and hover
  • Browse by Topic — Expand any topic to see all articles within
  • Clear Derivations — LaTeX formulas with step-by-step explanations
  • Code Examples — Python implementations using actual market data

1 Get Started

1.1 Foundations

Returns, volatility, Sharpe ratio, drawdowns, and correlation.

1.2 Portfolio Theory

Mean-variance optimization, efficient frontiers, and asset allocation.

1.3 Derivatives

Black-Scholes pricing, the Greeks, and volatility surfaces.

1.4 Time Series

Stationarity, GARCH models, and volatility forecasting.

1.5 Risk Management

Value at Risk, Expected Shortfall, and tail risk measurement.

1.6 Strategies

Momentum, mean reversion, and backtesting frameworks.

1.7 Microstructure

Order flow, bid-ask spreads, and market impact modeling.

1.8 Fixed Income

Yield curves, duration, convexity, and interest rate risk.

1.9 Machine Learning

Reinforcement learning, neural networks, and feature engineering.

2 Interactive Charts

Every article includes interactive charts. Drag to rotate, scroll to zoom, hover for details.

Example: Implied volatility surface showing the smile and term structure — key inputs for derivatives pricing.

3 Browse by Topic

Foundations

Sharpe Ratio

The Sharpe ratio measures excess return per unit of risk, enabling comparison across investments with different risk profiles.

January 13, 2026

Drawdowns

Drawdown analysis measures the decline from peak value, a critical risk metric for understanding worst-case scenarios.

January 13, 2026

Correlation

Correlation measures how assets move together, fundamental to portfolio diversification and risk management.

January 13, 2026

Returns

An introduction to simple and logarithmic returns, the fundamental metrics for measuring investment performance.

January 12, 2026

Random Sampling

An introduction to random sampling for selecting representative subsets from large datasets.

January 12, 2026

Geometric Brownian Motion

An introduction to Geometric Brownian Motion (GBM), the foundation of modern option pricing and Monte Carlo simulation.

January 12, 2026

Returns & Volatility

A foundational note on log returns, volatility measurement, and return distributions for liquid assets.

January 11, 2026
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Portfolio Theory

Mean-Variance Optimization

Mean-variance optimization finds the portfolio weights that maximize return for a given risk level, forming the efficient frontier.

January 13, 2026

Risk Parity

An introduction to risk parity, a strategy that allocates capital inversely proportional to asset volatility.

January 12, 2026
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Risk Management

Value at Risk

Value at Risk (VaR) estimates the maximum loss over a given time horizon at a specified confidence level.

January 13, 2026
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Derivatives

Black-Scholes Model

The Black-Scholes model provides closed-form solutions for European option prices, revolutionizing derivatives pricing.

January 13, 2026

Option Greeks

The Greeks measure how option prices change with respect to underlying parameters, essential for risk management and hedging.

January 13, 2026
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Time Series

Stationarity

Stationarity is a fundamental assumption in time series analysis—understanding when it holds and how to achieve it.

January 13, 2026

GARCH Models

GARCH models capture volatility clustering—the tendency for large price moves to follow large moves and small moves to follow small moves.

January 13, 2026
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Trading Strategies

Volatility Control

An introduction to volatility targeting, a strategy that scales portfolio exposure to maintain consistent risk levels.

January 14, 2026

Momentum

Momentum strategies profit from the tendency of assets that have performed well to continue performing well in the near term.

January 13, 2026
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Market Microstructure

Order Flow Analysis

An introduction to order flow analysis, bid-ask spreads, and market impact modeling.

January 19, 2026
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Fixed Income

Yield Curve Construction

An introduction to yield curve construction, bootstrapping, and interpolation methods.

January 19, 2026
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Machine Learning

Reinforcement Learning

Reinforcement learning enables agents to discover optimal strategies through trial-and-error interaction, mapping naturally to sequential trading decisions.

January 19, 2026
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4 Clear Derivations

Every formula is explained with its components. For example, sample standard deviation:

\[ \sigma = \sqrt{\frac{1}{n-1} \sum_{i=1}^{n} (x_i - \bar{x})^2} \]

Where:

  • \(\sigma\) — standard deviation
  • \(n\) — number of observations
  • \(x_i\) — each individual return
  • \(\bar{x}\) — mean of returns
  • \(n-1\) — Bessel’s correction for sample estimation

5 Code Examples

All formulas come with Python implementations using real data.

import numpy as np

# Sample returns data
returns = np.array([0.02, -0.01, 0.03, -0.02, 0.01, 0.04, -0.03, 0.02])

# Calculate standard deviation step by step
mean_return = np.mean(returns)
squared_deviations = (returns - mean_return) ** 2
variance = np.sum(squared_deviations) / (len(returns) - 1)
std_dev = np.sqrt(variance)

print(f"Mean return: {mean_return:.4f}")
print(f"Variance: {variance:.6f}")
print(f"Standard deviation: {std_dev:.4f}")
Mean return: 0.0075
Variance: 0.000621
Standard deviation: 0.0249

6 How to Use This Site

  • New to quant finance? Start with Foundations to build core intuition
  • Looking for something specific? Use the collapsible topics above or browse all articles
  • Browse by category? View all articles with category filters
  • Each article is self-contained — Read in any order, with links to prerequisites where needed
  • Latest articles? Browse all articles sorted by date
  • Learn more? Visit the About page for details on methodology and contact

This content is for educational purposes only and does not constitute financial advice. See full disclaimer.

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