activity
20202026
most citedNo-Transaction Band Network: A Neural Network Architecture for Efficient Deep Hedging

12 citations · 30 across the 16 of their papers we have counts for

collaborators

17 papers

q-fin.CP2026

Rethinking Synthetic Scenario Realism: Compatibility, Not Fidelity, Drives Hedging Performance

Ryuji Hashimoto, Masanori Hirano, Ryota Ozaki +1

Deep hedging has emerged as a data-driven approach to optimizing hedging strategies. Since real market data are often limited, synthetic price paths play a crucial role in training…

cs.CE2026

Uncovering Residual Factors in Financial Time Series via PCA and MTP2-constrained Gaussian Graphical Models

Koshi Watanabe, Ryota Ozaki, Kentaro Imajo +1

Financial time series are commonly decomposed into market factors, which capture shared price movements across assets, and residual factors, which reflect asset-specific deviations…

cs.CL2025

PLaMo 2 Technical Report

Preferred Networks, :, Kaizaburo Chubachi +24

In this report, we introduce PLaMo 2, a series of Japanese-focused large language models featuring a hybrid Samba-based architecture that transitions to full attention via continua…

cs.CL2025

A Judge-free LLM Open-ended Generation Benchmark Based on the Distributional Hypothesis

Kentaro Imajo, Masanori Hirano, Shuji Suzuki +1

Evaluating the open-ended text generation of large language models (LLMs) is challenging because of the lack of a clear ground truth and the high cost of human or LLM-based assessm…

q-fin.CP2024

Financial Fine-tuning a Large Time Series Model

Xinghong Fu, Masanori Hirano, Kentaro Imajo

Large models have shown unprecedented capabilities in natural language processing, image generation, and most recently, time series forecasting. This leads us to ask the question:…

cs.CL2024★ 3 cited

Enhancing Financial Domain Adaptation of Language Models via Model Augmentation

Kota Tanabe, Masanori Hirano, Kazuki Matoya +3

The domain adaptation of language models, including large language models (LLMs), has become increasingly important as the use of such models continues to expand. This study demons…

cs.CL2024

PLaMo-100B: A Ground-Up Language Model Designed for Japanese Proficiency

Preferred Elements, :, Kenshin Abe +18

We introduce PLaMo-100B, a large-scale language model designed for Japanese proficiency. The model was trained from scratch using 2 trillion tokens, with architecture such as QK No…

cs.CL2024

The Construction of Instruction-tuned LLMs for Finance without Instruction Data Using Continual Pretraining and Model Merging

Masanori Hirano, Kentaro Imajo

This paper proposes a novel method for constructing instruction-tuned large language models (LLMs) for finance without instruction data. Traditionally, developing such domain-speci…

cs.CL2024

Construction of Domain-specified Japanese Large Language Model for Finance through Continual Pre-training

Masanori Hirano, Kentaro Imajo

Large language models (LLMs) are now widely used in various fields, including finance. However, Japanese financial-specific LLMs have not been proposed yet. Hence, this study aims…

q-fin.CP2023★ 1 cited

Adversarial Deep Hedging: Learning to Hedge without Price Process Modeling

Masanori Hirano, Kentaro Minami, Kentaro Imajo

Deep hedging is a deep-learning-based framework for derivative hedging in incomplete markets. The advantage of deep hedging lies in its ability to handle various realistic market c…

q-fin.CP2023★ 2 cited

Efficient Learning of Nested Deep Hedging using Multiple Options

Masanori Hirano, Kentaro Imajo, Kentaro Minami +1

Deep hedging is a framework for hedging derivatives in the presence of market frictions. In this study, we focus on the problem of hedging a given target option by using multiple o…

q-fin.CP2022★ 1 cited

Uncertainty Aware Trader-Company Method: Interpretable Stock Price Prediction Capturing Uncertainty

Yugo Fujimoto, Kei Nakagawa, Kentaro Imajo +1

Machine learning is an increasingly popular tool with some success in predicting stock prices. One promising method is the Trader-Company~(TC) method, which takes into account the…

physics.soc-ph2022

Power Laws and Symmetries in a Minimal Model of Financial Market Economy

Liu Ziyin, Katsuya Ito, Kentaro Imajo +1

A financial market is a system resulting from the complex interaction between participants in a closed economy. We propose a minimal microscopic model of the financial market econo…

cs.LG2021★ 4 cited

Theoretically Motivated Data Augmentation and Regularization for Portfolio Construction

Liu Ziyin, Kentaro Minami, Kentaro Imajo

The task we consider is portfolio construction in a speculative market, a fundamental problem in modern finance. While various empirical works now exist to explore deep learning in…

q-fin.CP2021★ 12 cited

No-Transaction Band Network: A Neural Network Architecture for Efficient Deep Hedging

Shota Imaki, Kentaro Imajo, Katsuya Ito +2

Deep hedging (Buehler et al. 2019) is a versatile framework to compute the optimal hedging strategy of derivatives in incomplete markets. However, this optimal strategy is hard to…

q-fin.TR2020★ 6 cited

Trader-Company Method: A Metaheuristic for Interpretable Stock Price Prediction

Katsuya Ito, Kentaro Minami, Kentaro Imajo +1

Investors try to predict returns of financial assets to make successful investment. Many quantitative analysts have used machine learning-based methods to find unknown profitable m…

q-fin.PM2020★ 1 cited

Deep Portfolio Optimization via Distributional Prediction of Residual Factors

Kentaro Imajo, Kentaro Minami, Katsuya Ito +1

Recent developments in deep learning techniques have motivated intensive research in machine learning-aided stock trading strategies. However, since the financial market has a high…