Incorporating prior financial domain knowledge into neural networks for implied volatility surface prediction

In this paper we develop a novel neural network model for predicting implied volatility surface. Prior financial domain knowledge is taken into account. A new activation function that incorporates volatility smile is proposed, which is used for the hidden nodes that process the underlying asset price. In addition, financial conditions, such as the absence of arbitrage, the boundaries and the asymptotic slope, are embedded into the loss function. This is one of the very first studies which discuss a methodological framework that incorporates prior financial domain knowledge into neural network architecture design and model training. The proposed model outperforms the benchmarked models with the option data on the S&P 500 index over 20 years. More importantly, the domain knowledge is satisfied empirically, showing the model is consistent with the existing financial theories and conditions related to implied volatility surface.Comment: 8 pages, SIGKDD 202

Earnings prediction using machine learning methods and analyst comparison

In the course of this dissertation we propose an experimental study on how technical, macroeconomic, and financial variables, alongside analysts’ forecasts, can be used to optimize the prediction for the subsequent quarter’s earnings results using machine learning, comparing the performance of the models to analysts’ forecasts. The dissertation includes three steps. In step one, an event study is conducted to test abnormal returns in firms’ stock prices in the day following earnings announcement, grouped by earnings per share (EPS) growth in classes of size 3, 6 and 9, computed for each quarter. In step two, several machine learning models are built to maximize the accuracy of EPS predictions. In the last step, investment strategies are constructed to take advantage of investors’ expectations, which are closely correlated with analysts’ predictions. In the backdrop of an exhaustive analysis on quarterly earnings predictions using machine learning methods, conclusions are drawn related to the superiority of the CatBoost classifier. All machine learning models tested underperform analyst predictions, which could be explained by the time and privileged information at analysts’ disposal, as well as their selection of firms to cover. Regardless, machine learning models can be used as a confirmation for analyst predictions, and statistically significant investment strategies are pursued with those fundamentals. Importantly, high confidence predictions by machine learning models are significantly more accurate than the average accuracy of forecasts.No decorrer desta dissertação, realiza-se um estudo experimental sobre a forma como análises técnicas, macroeconómicas, fundamentais e as previsões dos analistas podem ser utilizadas em conjunto para otimizar a previsão dos resultados de lucros do próximo trimestre de empresas A dissertação inclui três etapas. Na primeira etapa, é efetuado um estudo de evento para testar os retornos anormais nas ações no dia seguinte aos anúncios de lucros, sendo estes agrupados pelo crescimento do lucro por ação nas classes de 3, 6 e 9, calculado para cada trimestre. Na etapa dois, vários modelos de machine learning (ML) são concebidos para maximizar a precisão das previsões de crescimento de lucros de empresas. Na última etapa, estratégias de investimento são construídas para tirar proveito das expectativas do investidor, que estão relacionadas com as previsões dos analistas. Uma vez que um dos projetos de pesquisa mais exaustivos sobre previsões de lucros para o próximo trimestre, conclusões podem ser retiradas relacionadas com a superioridade do modelo CatBoost nas previsões de lucros. Todos os modelos de testados apresentam desempenho inferior às previsões dos analistas, o que pode ser explicado pelo tempo e pelas informações privilegiadas a que os analistas têm acesso, bem como pela escolha da empresa sob a qual as suas previsões incidem. Os modelos de podem ser utilizados como uma confirmação para as previsões dos analistas criando estratégias de investimento estatisticamente significativas. Além disso, as previsões com alta confiança por modelos de são mais precisas do que a precisão média das previsões dos analistas

A Novel Distributed Representation of News (DRNews) for Stock Market Predictions

In this study, a novel Distributed Representation of News (DRNews) model is developed and applied in deep learning-based stock market predictions. With the merit of integrating contextual information and cross-documental knowledge, the DRNews model creates news vectors that describe both the semantic information and potential linkages among news events through an attributed news network. Two stock market prediction tasks, namely the short-term stock movement prediction and stock crises early warning, are implemented in the framework of the attention-based Long Short Term-Memory (LSTM) network. It is suggested that DRNews substantially enhances the results of both tasks comparing with five baselines of news embedding models. Further, the attention mechanism suggests that short-term stock trend and stock market crises both receive influences from daily news with the former demonstrates more critical responses on the information related to the stock market {\em per se}, whilst the latter draws more concerns on the banking sector and economic policies.Comment: 25 page

PreBit -- A multimodal model with Twitter FinBERT embeddings for extreme price movement prediction of Bitcoin

Bitcoin, with its ever-growing popularity, has demonstrated extreme price volatility since its origin. This volatility, together with its decentralised nature, make Bitcoin highly subjective to speculative trading as compared to more traditional assets. In this paper, we propose a multimodal model for predicting extreme price fluctuations. This model takes as input a variety of correlated assets, technical indicators, as well as Twitter content. In an in-depth study, we explore whether social media discussions from the general public on Bitcoin have predictive power for extreme price movements. A dataset of 5,000 tweets per day containing the keyword `Bitcoin' was collected from 2015 to 2021. This dataset, called PreBit, is made available online. In our hybrid model, we use sentence-level FinBERT embeddings, pretrained on financial lexicons, so as to capture the full contents of the tweets and feed it to the model in an understandable way. By combining these embeddings with a Convolutional Neural Network, we built a predictive model for significant market movements. The final multimodal ensemble model includes this NLP model together with a model based on candlestick data, technical indicators and correlated asset prices. In an ablation study, we explore the contribution of the individual modalities. Finally, we propose and backtest a trading strategy based on the predictions of our models with varying prediction threshold and show that it can used to build a profitable trading strategy with a reduced risk over a `hold' or moving average strategy.Comment: 21 pages, submitted preprint to Elsevier Expert Systems with Application

Machine Learning Stock Market Prediction Studies: Review and Research Directions

Stock market investment strategies are complex and rely on an evaluation of vast amounts of data. In recent years, machine learning techniques have increasingly been examined to assess whether they can improve market forecasting when compared with traditional approaches. The objective for this study is to identify directions for future machine learning stock market prediction research based upon a review of current literature. A systematic literature review methodology is used to identify relevant peer-reviewed journal articles from the past twenty years and categorize studies that have similar methods and contexts. Four categories emerge: artificial neural network studies, support vector machine studies, studies using genetic algorithms combined with other techniques, and studies using hybrid or other artificial intelligence approaches. Studies in each category are reviewed to identify common findings, unique findings, limitations, and areas that need further investigation. The final section provides overall conclusions and directions for future research