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The global energy market has significantly developed in recent years; proof of this is the creation and promotion of smart grids and technical advances in energy commercialization and transmission. Specifically in the Brazilian context, with the recent modernization of the electricity sector, energy trading prices, previously published on a weekly frequency, are now available on an hourly domain. In this context, the definition and forecasting of prices become increasingly important factors for the economic and financial viability of energy projects. In this scenario of changes in the local regulatory framework, there is a lack of publications based on the new hourly prices in Brazil. This paper presents, in a pioneering way, the Dynamic Time Scan Forecasting (DTSF) method for forecasting hourly energy prices in Brazil. This method searches for similarity patterns in time series and, in previous investigations, showed competitive advantages concerning established forecasting methods. This research aims to test the accuracy of the DTSF method against classical statistical models and machine learning. We used the short-term prices of electricity in Brazil, made available by the Electric Energy Commercialization Chamber. The new DTSF model showed the best predictive performance compared to both the statistical and machine learning models. The DTSF performance was superior considering the evaluation metrics utilized in this paper. We verified that the predictions made by the DTSF showed less variability compared to the other models. Finally, we noticed that there is not an ideal model for all predictive 24 steps ahead forecasts, but there are better models at certain times of the day. [ABSTRACT FROM AUTHOR]

The remarkable flexibility and adaptability of both deep learning models and ensemble methods have led to the proliferation for their application in understanding many physical phenomena. Traditionally, these two techniques have largely been treated as independent methodologies in practical applications. This study develops an optimized ensemble deep learning framework wherein these two machine learning techniques are jointly used to achieve synergistic improvements in model accuracy, stability, scalability, and reproducibility, prompting a new wave of applications in the forecasting of dynamics. Unpredictability is considered one of the key features of chaotic dynamics; therefore, forecasting such dynamics of nonlinear systems is a relevant issue in the scientific community. It becomes more challenging when the prediction of extreme events is the focus issue for us. In this circumstance, the proposed optimized ensemble deep learning (OEDL) model based on a best convex combination of feed-forward neural networks, reservoir computing, and long short-term memory can play a key role in advancing predictions of dynamics consisting of extreme events. The combined framework can generate the best out-of-sample performance than the individual deep learners and standard ensemble framework for both numerically simulated and real-world data sets. We exhibit the outstanding performance of the OEDL framework for forecasting extreme events generated from a Liénard-type system, prediction of COVID-19 cases in Brazil, dengue cases in San Juan, and sea surface temperature in the Niño 3.4 region. [ABSTRACT FROM AUTHOR]