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 trend and seasonality


Guidelines for Augmentation Selection in Contrastive Learning for Time Series Classification

Liu, Ziyu, Alavi, Azadeh, Li, Minyi, Zhang, Xiang

arXiv.org Artificial Intelligence

Self-supervised contrastive learning has become a key technique in deep learning, particularly in time series analysis, due to its ability to learn meaningful representations without explicit supervision. Augmentation is a critical component in contrastive learning, where different augmentations can dramatically impact performance, sometimes influencing accuracy by over 30%. However, the selection of augmentations is predominantly empirical which can be suboptimal, or grid searching that is time-consuming. In this paper, we establish a principled framework for selecting augmentations based on dataset characteristics such as trend and seasonality. Specifically, we construct 12 synthetic datasets incorporating trend, seasonality, and integration weights. We then evaluate the effectiveness of 8 different augmentations across these synthetic datasets, thereby inducing generalizable associations between time series characteristics and augmentation efficiency. Additionally, we evaluated the induced associations across 6 real-world datasets encompassing domains such as activity recognition, disease diagnosis, traffic monitoring, electricity usage, mechanical fault prognosis, and finance. These real-world datasets are diverse, covering a range from 1 to 12 channels, 2 to 10 classes, sequence lengths of 14 to 1280, and data frequencies from 250 Hz to daily intervals. The experimental results show that our proposed trend-seasonality-based augmentation recommendation algorithm can accurately identify the effective augmentations for a given time series dataset, achieving an average Recall@3 of 0.667, outperforming baselines. Our work provides guidance for studies employing contrastive learning in time series analysis, with wide-ranging applications. All the code, datasets, and analysis results will be released at https://github.com/DL4mHealth/TS-Contrastive-Augmentation-Recommendation.


Time Series Transformation for Deep Learning

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As the field of deep learning continues to evolve and expand, time series data is becoming increasingly important in a variety of applications, including finance, medicine, and manufacturing. However, working with time series data presents unique challenges, including the need for proper transformation in order to effectively train deep learning models. In this article, we'll explore the ins and outs of time series transformation for deep learning and how it can help you achieve better results. Time series data is a sequence of observations recorded over a period of time, such as stock prices, weather patterns, or sensor readings. In many cases, time series data contains important information that can be used to make predictions or identify patterns, but working with this type of data presents unique challenges.


[100%OFF] Marketing Analytics: Forecasting Models With Excel

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You're looking for a complete course on understanding Forecasting models and forecasting analytics to drive business decisions involving production schedules, inventory management, manpower planning, demand forecasting, and many other parts of the business., right? You've found the right Marketing Analytics: Forecasting Models with Excel! This course teaches you everything you need to know about different forecasting models and how to implement these models for devising forecasting analytics in Excel using advanced excel tool. How this course will help you? A Verifiable Certificate of Completion is presented to all students who undertake this Marketing Analytics: Forecasting Models with Excel course.


Machine Learning for Time-Series with Python

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The term time-series analysis (TSA) refers to the statistical approach to time-series or the analysis of trend and seasonality. It is often an ad hoc exploration and analysis that usually involves visualizing distributions, trends, cyclic patterns, and relationships between features, and between features and the target(s). More generally, we can say TSA is roughly exploratory data analysis (EDA) that's specific to time-series data. This comparison can be misleading however since TSA can include both descriptive and exploratory elements. Let's see quickly the differences between descriptive and exploratory analysis: Therefore, TSA is the initial investigation of a dataset with the goal of discovering patterns, especially trend and seasonality, and obtaining initial insights, testing hypotheses, and extracting meaningful summary statistics.


Progressive Growing of Neural ODEs

Ayyubi, Hammad A., Yao, Yi, Divakaran, Ajay

arXiv.org Machine Learning

Neural Ordinary Differential Equations (NODEs) have proven to be a powerful modeling tool for approximating (interpolation) and forecasting (extrapolation) irregularly sampled time series data. However, their performance degrades substantially when applied to real-world data, especially long-term data with complex behaviors (e.g., long-term trend across years, mid-term seasonality across months, and short-term local variation across days). To address the modeling of such complex data with different behaviors at different frequencies (time spans), we propose a novel progressive learning paradigm of NODEs for long-term time series forecasting. Specifically, following the principle of curriculum learning, we gradually increase the complexity of data and network capacity as training progresses. Our experiments with both synthetic data and real traffic data (PeMS Bay Area traffic data) show that our training methodology consistently improves the performance of vanilla NODEs by over 64%.


Predict Electricity Consumption Using Time Series Analysis - KDnuggets

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"Time series models are used to forecast future events based on previous events that have been observed (and data collected) at regular time intervals." We will be taking a small forecasting problem and try to solve it till the end learning time series forecasting alongside. Time series forecasting is a technique for the prediction of events through a sequence of time. The technique is used across many fields of study, from geology to behavior to economics. The techniques predict future events by analyzing the trends of the past, on the assumption that future trends will hold similar to historical trends. Time series forecasting is sometimes just the analysis of experts studying a field and offering their predictions.


Predict electricity consumption using Time Series analysis

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"Time series models are used to forecast future events based on previous events that have been observed (and data collected) at regular time intervals." We will be taking a small forecasting problem and try to solve it till the end learning time series forecasting alongside. Time series forecasting is a technique for the prediction of events through a sequence of time. The technique is used across many fields of study, from geology to behavior to economics. The techniques predict future events by analyzing the trends of the past, on the assumption that future trends will hold similar to historical trends.


Beginner's Guide for time-series forecasting Dimensionless Blog

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Time series analysis is the use of statistical methods to analyze time series data and extract meaningful statistics and characteristics of the data. In this blog, we will begin our journey of learning time series forecasting using python. We will be taking a small forecasting problem and try to solve it till the end learning time series forecasting alongside. Time series analysis is the collection of data at specific intervals over a period of time, with the purpose of identifying trends, cycles, and seasonal variances to aid in the forecasting of a future event. Data is any observed outcome that's measurable. Unlike in statistical sampling, in time series analysis, data must be measured over time at consistent intervals to identify patterns that form trends, cycles, and seasonal variances. Measurements at random intervals lose the ability to predict future events.


Bitcoin price forecasting with deep learning algorithms

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Disclaimer: All the information in this article including the algorithm was provided and published for educational purpose only, not a solicitation for investment nor investment advice. Any reliance you place on such information is therefore strictly at your own risk. Bitcoin is the first decentralized digital currency. This means it is not governed by any central bank or some other authority. This cryptocurrency was created in 2009 but it became extremely popular in 2017.