GluonTS - Probabilistic Time Series Modeling in Python

GluonTS is a Python package for probabilistic time series modeling, focusing on deep learning based models.

Features

• State-of-the-art models implemented with MXNet and PyTorch (see list)
• Easy AWS integration via Amazon SageMaker (see here)
• Utilities for loading and iterating over time series datasets
• Utilities to evaluate models performance and compare their accuracy
• Building blocks to define custom models and quickly experiment

Installation

GluonTS requires Python 3.7, and the easiest way to install it is via pip:

pip install --upgrade gluonts mxnet~=1.8   # to be able to use MXNet-based models
pip install --upgrade gluonts torch~=1.10  # to be able to use PyTorch-based models

Documentation

• Documentation (stable version)
• Documentation (development version)
• JMLR MLOSS Paper
• ArXiv Paper

Available models

Name	Local/global	Data layout	Architecture/method	Implementation	References
DeepAR	Global	Univariate	RNN	MXNet, PyTorch	paper
DeepState	Global	Univariate	RNN, state-space model	MXNet	paper
DeepFactor	Global	Univariate	RNN, state-space model, Gaussian process	MXNet	paper
Deep Renewal Processes	Global	Univariate	RNN	MXNet	paper
GPForecaster	Global	Univariate	MLP, Gaussian process	MXNet	-
MQ-CNN	Global	Univariate	CNN encoder, MLP decoder	MXNet	paper
MQ-RNN	Global	Univariate	RNN encoder, MLP encoder	MXNet	paper
N-BEATS	Global	Univariate	MLP, residual links	MXNet	paper
Rotbaum	Global	Univariate	XGBoost, Quantile Regression Forests, LightGBM, Level Set Forecaster	Numpy	paper
Causal Convolutional Transformer	Global	Univariate	Causal convolution, self attention	MXNet	paper
Temporal Fusion Transformer	Global	Univariate	LSTM, self attention	MXNet	paper
Transformer	Global	Univariate	MLP, multi-head attention	MXNet	paper
WaveNet	Global	Univariate	Dilated convolution	MXNet	paper
SimpleFeedForward	Global	Univariate	MLP	MXNet, PyTorch	-
DeepVAR	Global	Multivariate	RNN	MXNet	paper
GPVAR	Global	Multivariate	RNN, Gaussian process	MXNet	paper
LSTNet	Global	Multivariate	LSTM	MXNet	paper
DeepTPP	Global	Multivariate events	RNN, temporal point process	MXNet	paper
RForecast	Local	Univariate	ARIMA, ETS, Croston, TBATS	Wrapped R package	paper
Prophet	Local	Univariate	-	Wrapped Python package	paper
NaiveSeasonal	Local	Univariate	-	Numpy	book section
Naive2	Local	Univariate	-	Numpy	book section
NPTS	Local	Univariate	-	Numpy	-

Running on Amazon SageMaker

Training and deploying GluonTS models on Amazon SageMaker is easily done by using the gluonts.shell package, see its README for more information. Dockerfiles compatible with Amazon SageMaker can be found in the examples/dockerfiles folder.

Quick example

This simple example illustrates how to train a model from GluonTS on some data, and then use it to make predictions. For more extensive example, please refer to the tutorial section of the documentation

As a first step, we need to collect some data: in this example we will use the volume of tweets mentioning the AMZN ticker symbol.

import pandas as pd
url = "https://raw.githubusercontent.com/numenta/NAB/master/data/realTweets/Twitter_volume_AMZN.csv"
df = pd.read_csv(url, header=0, index_col=0)

The first 100 data points look like follows:

import matplotlib.pyplot as plt
df[:100].plot(linewidth=2)
plt.grid(which='both')
plt.show()

We can now prepare a training dataset for our model to train on. Datasets in GluonTS are essentially iterable collections of dictionaries: each dictionary represents a time series with possibly associated features. For this example, we only have one entry, specified by the "start" field which is the timestamp of the first datapoint, and the "target" field containing time series data. For training, we will use data up to midnight on April 5th, 2015.

from gluonts.dataset.common import ListDataset
training_data = ListDataset(
    [{"start": df.index[0], "target": df.value[:"2015-04-05 00:00:00"]}],
    freq = "5min"
)

A forecasting model in GluonTS is a predictor object. One way of obtaining predictors is by training a correspondent estimator. Instantiating an estimator requires specifying the frequency of the time series that it will handle, as well as the number of time steps to predict. In our example we're using 5 minutes data, so freq="5min", and we will train a model to predict the next hour, so prediction_length=12. We also specify some minimal training options.

from gluonts.model.deepar import DeepAREstimator
from gluonts.mx.trainer import Trainer

estimator = DeepAREstimator(freq="5min", prediction_length=12, trainer=Trainer(epochs=10))
predictor = estimator.train(training_data=training_data)

During training, useful information about the progress will be displayed. To get a full overview of the available options, please refer to the documentation of DeepAREstimator (or other estimators) and Trainer.

We're now ready to make predictions: we will forecast the hour following the midnight on April 15th, 2015.

test_data = ListDataset(
    [{"start": df.index[0], "target": df.value[:"2015-04-15 00:00:00"]}],
    freq = "5min"
)

from gluonts.dataset.util import to_pandas

for test_entry, forecast in zip(test_data, predictor.predict(test_data)):
    to_pandas(test_entry)[-60:].plot(linewidth=2)
    forecast.plot(color='g', prediction_intervals=[50.0, 90.0])
plt.grid(which='both')

Note that the forecast is displayed in terms of a probability distribution: the shaded areas represent the 50% and 90% prediction intervals, respectively, centered around the median (dark green line).

Contributing

If you wish to contribute to the project, please refer to our contribution guidelines.

Citing

If you use GluonTS in a scientific publication, we encourage you to add the following references to the related papers, in addition to any model-specific references that are relevant for your work:

@article{gluonts_jmlr,
  author  = {Alexander Alexandrov and Konstantinos Benidis and Michael Bohlke-Schneider
    and Valentin Flunkert and Jan Gasthaus and Tim Januschowski and Danielle C. Maddix
    and Syama Rangapuram and David Salinas and Jasper Schulz and Lorenzo Stella and
    Ali Caner Türkmen and Yuyang Wang},
  title   = {{GluonTS: Probabilistic and Neural Time Series Modeling in Python}},
  journal = {Journal of Machine Learning Research},
  year    = {2020},
  volume  = {21},
  number  = {116},
  pages   = {1-6},
  url     = {http://jmlr.org/papers/v21/19-820.html}
}

@article{gluonts_arxiv,
  author  = {Alexandrov, A. and Benidis, K. and Bohlke-Schneider, M. and
    Flunkert, V. and Gasthaus, J. and Januschowski, T. and Maddix, D. C.
    and Rangapuram, S. and Salinas, D. and Schulz, J. and Stella, L. and
    Türkmen, A. C. and Wang, Y.},
  title   = {{GluonTS: Probabilistic Time Series Modeling in Python}},
  journal = {arXiv preprint arXiv:1906.05264},
  year    = {2019}
}

Other resources

• Collected Papers from the group behind GluonTS: a bibliography.
• Tutorial at IJCAI 2021 (with videos) with YouTube link.
• Tutorial at WWW 2020 (with videos)
• Tutorial at SIGMOD 2019
• Tutorial at KDD 2019
• Tutorial at VLDB 2018
• Neural Time Series with GluonTS
• International Symposium of Forecasting: Deep Learning for Forecasting workshop