Markowitz Variance May Vastly Undervalue or Overestimate Portfolio Variance and Risks

We consider the investor who doesn’t trade shares of his portfolio. The investor only observes the current trades made in the market with his securities to estimate the current return, variance, and risks of his unchanged portfolio. We show how the time series of consecutive trades made in the marke

July 29, 2025 · 3 min · thequant.space

Quantum generative modeling for financial time series with temporal correlations

Quantum generative adversarial networks (QGANs) have been investigated as a method for generating synthetic data with the goal of augmenting training data sets for neural networks. This is especially relevant for financial time series, since we only ever observe one realization of the process, namel

July 29, 2025 · 2 min · thequant.space

Deep Reputation Scoring in DeFi: zScore-Based Wallet Ranking from Liquidity and Trading Signals

As decentralized finance (DeFi) evolves, distinguishing between user behaviors - liquidity provision versus active trading - has become vital for risk modeling and on-chain reputation. We propose a behavioral scoring framework for Uniswap that assigns two complementary scores: a Liquidity Provision

July 28, 2025 · 2 min · thequant.space

Determinants of Saving Behavior Among Employees in Dhaka, Bangladesh

Purpose With an emphasis on elements like financial knowledge, financial attitude, social influence, financial self-efficacy, and financial management practices, this study explores the factors that influence employees’ saving behavior in Dhaka, Bangladesh. We also welcome others to work on saving b

July 28, 2025 · 2 min · thequant.space

Slomads Rising: Stay Length Shifts in Digital Nomad Travel, United States 2019-2024

Using all U.S. Airbnb reservations created in 2019-2024 (booking-count weighted), we quantify pandemic-era shifts in nights per booking (NPB) and the mechanism behind them. The mean rose from 3.68 pre-COVID to 4.36 during restrictions and stabilized near 4.07 post-2021 (about 10% above 2019); the bo

July 28, 2025 · 2 min · thequant.space

Your AI, Not Your View: The Bias of LLMs in Investment Analysis

In finance, Large Language Models (LLMs) face frequent knowledge conflicts arising from discrepancies between their pre-trained parametric knowledge and real-time market data. These conflicts are especially problematic in real-world investment services, where a model’s inherent biases can misalign w

July 28, 2025 · 2 min · thequant.space

Learning from Expert Factors: Trajectory-level Reward Shaping for Formulaic Alpha Mining

Reinforcement learning (RL) has successfully automated the complex process of mining formulaic alpha factors, for creating interpretable and profitable investment strategies. However, existing methods are hampered by the sparse rewards given the underlying Markov Decision Process. This inefficiency

July 27, 2025 · 2 min · thequant.space

Lévy-Driven Option Pricing without a Riskless Asset

We extend the Lindquist-Rachev (LR) option-pricing framework–which values derivatives in markets lacking a traded risk-free bond–by introducing common Levy jump dynamics across two risky assets. The resulting endogenous “shadow” short rate replaces the usual risk-free yield and governs discounting

July 27, 2025 · 2 min · thequant.space

Technical Indicator Networks (TINs): An Interpretable Neural Architecture Modernizing Classic al Technical Analysis for Adaptive Algorithmic Trading

Deep neural networks (DNNs) have transformed fields such as computer vision and natural language processing by employing architectures aligned with domain-specific structural patterns. In algorithmic trading, however, there remains a lack of architectures that directly incorporate the logic of tradi

July 27, 2025 · 2 min · thequant.space

Dependency Network-Based Portfolio Design with Forecasting and VaR Constraints

This study proposes a novel portfolio optimization framework that integrates statistical social network analysis with time series forecasting and risk management. Using daily stock data from the S&P 500 (2020-2024), we construct dependency networks via Vector Autoregression (VAR) and Forecast Error

July 26, 2025 · 2 min · thequant.space

Optimal mean-variance portfolio selection under regime-switching-induced stock price shocks

In this paper, we investigate mean-variance (MV) portfolio selection problems with jumps in a regime-switching financial model. The novelty of our approach lies in allowing not only the market parameters – such as the interest rate, appreciation rate, volatility, and jump intensity – to depend on th

July 26, 2025 · 2 min · thequant.space

Existence of Strong Randomized Equilibria in Mean-Field Games of Optimal Stopping with Common Noise

We study a mean-field game of optimal stopping and investigate the existence of strong solutions via a connection with the Bank-El Karoui’s representation problem. Under certain continuity assumptions, where the common noise is generated by a countable partition, we show that a strong randomized mea

July 25, 2025 · 2 min · thequant.space

Implementing Credit Risk Analysis with Quantum Singular Value Transformation

The analysis of credit risk is crucial for the efficient operation of financial institutions. Quantum Amplitude Estimation (QAE) offers the potential for a quadratic speed-up over classical methods used to estimate metrics such as Value at Risk (VaR) and Conditional Value at Risk (CVaR). However, nu

July 25, 2025 · 2 min · thequant.space

Modeling Excess Mortality and Interest Rates using Mixed Fractional Brownian Motions

Recent studies have identified long-range dependence as a key feature in the dynamics of both mortality and interest rates. Building on this insight, we develop a novel bi-variate stochastic framework based on mixed fractional Brownian motions to jointly model their long-memory behavior and instanta

July 25, 2025 · 2 min · thequant.space

Negative redispatch power for green hydrogen production: Game changer or lame duck? A German perspective

Following years of controversial discussions about the risks of market-based redispatch, the German transmission network operators finally installed regional redispatch markets by the end of 2024. Since water electrolysers are eligible market participants, the otherwise downwards redispatched renewa

July 25, 2025 · 2 min · thequant.space

Combination of traditional and parametric insurance: calibration method based on the optimization of a criterion adapted to heavy tail losses

In this paper, we address the problem of providing insurance protection against heavy-tailed losses, for which the expected loss may not even be finite. The product we study is based on a combination of traditional insurance up to a given limit and a parametric (or index-based) cover for larger loss

July 24, 2025 · 2 min · thequant.space

Evaluating Large Language Models (LLMs) in Financial NLP: A Comparative Study on Financial Report Analysis

Large Language Models (LLMs) have demonstrated remarkable capabilities across a wide variety of Financial Natural Language Processing (FinNLP) tasks. However, systematic comparisons among widely used LLMs remain underexplored. Given the rapid advancement and growing influence of LLMs in financial an

July 24, 2025 · 2 min · thequant.space

FinDPO: Financial Sentiment Analysis for Algorithmic Trading through Preference Optimization of LLMs

Opinions expressed in online finance-related textual data are having an increasingly profound impact on trading decisions and market movements. This trend highlights the vital role of sentiment analysis as a tool for quantifying the nature and strength of such opinions. With the rapid development of

July 24, 2025 · 2 min · thequant.space

Forecasting Commodity Price Shocks Using Temporal and Semantic Fusion of Prices Signals and Agentic Generative AI Extracted Economic News

Accurate forecasting of commodity price spikes is vital for countries with limited economic buffers, where sudden increases can strain national budgets, disrupt import-reliant sectors, and undermine food and energy security. This paper introduces a hybrid forecasting framework that combines historic

July 24, 2025 · 2 min · thequant.space

HARLF: Hierarchical Reinforcement Learning and Lightweight LLM-Driven Sentiment Integration for Financial Portfolio Optimization

This paper presents a novel hierarchical framework for portfolio optimization, integrating lightweight Large Language Models (LLMs) with Deep Reinforcement Learning (DRL) to combine sentiment signals from financial news with traditional market indicators. Our three-tier architecture employs base RL

July 24, 2025 · 2 min · thequant.space