Improving Irregularly Sampled Time Series Learning with Dense
Descriptors of Time
- URL: http://arxiv.org/abs/2003.09291v1
- Date: Fri, 20 Mar 2020 14:21:25 GMT
- Title: Improving Irregularly Sampled Time Series Learning with Dense
Descriptors of Time
- Authors: Rafael T. Sousa, Lucas A. Pereira, Anderson S. Soares
- Abstract summary: Supervised learning with irregularly sampled time series have been a challenge to Machine Learning methods.
This work propose a novel method to represent timestamps as dense vectors using sinusoidal functions, called Time Embeddings.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Supervised learning with irregularly sampled time series have been a
challenge to Machine Learning methods due to the obstacle of dealing with
irregular time intervals. Some papers introduced recently recurrent neural
network models that deals with irregularity, but most of them rely on complex
mechanisms to achieve a better performance. This work propose a novel method to
represent timestamps (hours or dates) as dense vectors using sinusoidal
functions, called Time Embeddings. As a data input method it and can be applied
to most machine learning models. The method was evaluated with two predictive
tasks from MIMIC III, a dataset of irregularly sampled time series of
electronic health records. Our tests showed an improvement to LSTM-based and
classical machine learning models, specially with very irregular data.
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