Nixtla
⚡️
Forecast
Statistical Lightning fast forecasting with statistical and econometric models
StatsForecast offers a collection of widely used univariate time series forecasting models, including exponential smoothing and automatic ARIMA
modeling optimized for high performance using numba
.
🔥
Highlights
- Fastest and most accurate
auto_arima
inPython
andR
. - New!: Replace FB-Prophet in two lines of code and gain speed and accuracy. Check the experiments here.
- New!: Distributed computation in clusters with ray. (Forecast 1M series in 30min)
- New!: Good Ol' sklearn syntax with
AutoARIMA().fit(y).predict(h=7)
.
🎊
Features
- Inclusion of
exogenous variables
andprediction intervals
. - Out of the box implementation of
exponential smoothing
,croston
,seasonal naive
,random walk with drift
andtbs
. - 20x faster than
pmdarima
. - 1.5x faster than
R
. - 500x faster than
Prophet
. - Compiled to high performance machine code through
numba
. - 1,000,000 series in 30 min with ray.
Missing something? Please open an issue or write us in
📖
Why?
Current Python alternatives for statistical models are slow and inaccurate. So we created a library that can be used to forecast in production environments or as benchmarks. StatsForecast
includes an extensive battery of models that can efficiently fit thousands of time series.
🔬
Accuracy
We compared accuracy and speed against: pmdarima, Rob Hyndman's forecast package and Facebook's Prophet. We used the Daily
, Hourly
and Weekly
data from the M4 competition.
The following table summarizes the results. As can be seen, our auto_arima
is the best model in accuracy (measured by the MASE
loss) and time, even compared with the original implementation in R.
dataset | metric | nixtla | pmdarima [1] | auto_arima_r | prophet |
---|---|---|---|---|---|
M4-Daily | MASE | 3.26 | 3.35 | 4.46 | 14.26 |
M4-Daily | time | 1.41 | 27.61 | 1.81 | 514.33 |
M4-Hourly | MASE | 0.92 | --- | 1.02 | 1.78 |
M4-Hourly | time | 12.92 | --- | 23.95 | 17.27 |
M4-Weekly | MASE | 2.34 | 2.47 | 2.58 | 7.29 |
M4-Weekly | time | 0.42 | 2.92 | 0.22 | 19.82 |
[1] The model auto_arima
from pmdarima
had problems with Hourly data. An issue was opened in their repo.
The following table summarizes the data details.
group | n_series | mean_length | std_length | min_length | max_length |
---|---|---|---|---|---|
Daily | 4,227 | 2,371 | 1,756 | 107 | 9,933 |
Hourly | 414 | 901 | 127 | 748 | 1,008 |
Weekly | 359 | 1,035 | 707 | 93 | 2,610 |
⏲
Computational efficiency
We measured the computational time against the number of time series. The following graph shows the results. As we can see, the fastest model is our auto_arima
.
You can reproduce the results here.
External regressors
Results with external regressors are qualitatively similar to the reported before. You can find the complete experiments here.
👾
Less code
📖
Documentation
Here is a link to the documentation.
🧬
Getting Started
💻
Installation
PyPI
You can install the released version of StatsForecast
from the Python package index with:
pip install statsforecast
(Installing inside a python virtualenvironment or a conda environment is recommended.)
Conda
Also you can install the released version of StatsForecast
from conda with:
conda install -c conda-forge statsforecast
(Installing inside a python virtualenvironment or a conda environment is recommended.)
Dev Mode
If you want to make some modifications to the code and see the effects in real time (without reinstalling), follow the steps below:git clone https://github.com/Nixtla/statsforecast.git
cd statsforecast
pip install -e .
🧬
How to use
The following example needs ipython
and matplotlib
as additional packages. If not installed, install it via your preferred method, e.g. pip install ipython matplotlib
.
import numpy as np
import pandas as pd
from IPython.display import display, Markdown
import matplotlib.pyplot as plt
from statsforecast import StatsForecast
from statsforecast.models import seasonal_naive, auto_arima
from statsforecast.utils import AirPassengers
horizon = 12
ap_train = AirPassengers[:-horizon]
ap_test = AirPassengers[-horizon:]
series_train = pd.DataFrame(
{
'ds': pd.date_range(start='1949-01-01', periods=ap_train.size, freq='M'),
'y': ap_train
},
index=pd.Index([0] * ap_train.size, name='unique_id')
)
fcst = StatsForecast(
series_train,
models=[(auto_arima, 12), (seasonal_naive, 12)],
freq='M',
n_jobs=1
)
forecasts = fcst.forecast(12, level=(80, 95))
forecasts['y_test'] = ap_test
fig, ax = plt.subplots(1, 1, figsize = (20, 7))
df_plot = pd.concat([series_train, forecasts]).set_index('ds')
df_plot[['y', 'y_test', 'auto_arima_season_length-12_mean', 'seasonal_naive_season_length-12']].plot(ax=ax, linewidth=2)
ax.fill_between(df_plot.index,
df_plot['auto_arima_season_length-12_lo-80'],
df_plot['auto_arima_season_length-12_hi-80'],
alpha=.35,
color='green',
label='auto_arima_level_80')
ax.fill_between(df_plot.index,
df_plot['auto_arima_season_length-12_lo-95'],
df_plot['auto_arima_season_length-12_hi-95'],
alpha=.2,
color='green',
label='auto_arima_level_95')
ax.set_title('AirPassengers Forecast', fontsize=22)
ax.set_ylabel('Monthly Passengers', fontsize=20)
ax.set_xlabel('Timestamp [t]', fontsize=20)
ax.legend(prop={'size': 15})
ax.grid()
for label in (ax.get_xticklabels() + ax.get_yticklabels()):
label.set_fontsize(20)
Adding external regressors
series_train['trend'] = np.arange(1, ap_train.size + 1)
series_train['intercept'] = np.ones(ap_train.size)
series_train['month'] = series_train['ds'].dt.month
series_train = pd.get_dummies(series_train, columns=['month'], drop_first=True)
display_df(series_train.head())
unique_id | ds | y | trend | intercept | month_2 | month_3 | month_4 | month_5 | month_6 | month_7 | month_8 | month_9 | month_10 | month_11 | month_12 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0 | 1949-01-31 00:00:00 | 112 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
0 | 1949-02-28 00:00:00 | 118 | 2 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
0 | 1949-03-31 00:00:00 | 132 | 3 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
0 | 1949-04-30 00:00:00 | 129 | 4 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
0 | 1949-05-31 00:00:00 | 121 | 5 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
xreg_test = pd.DataFrame(
{
'ds': pd.date_range(start='1960-01-01', periods=ap_test.size, freq='M')
},
index=pd.Index([0] * ap_test.size, name='unique_id')
)
xreg_test['trend'] = np.arange(133, ap_test.size + 133)
xreg_test['intercept'] = np.ones(ap_test.size)
xreg_test['month'] = xreg_test['ds'].dt.month
xreg_test = pd.get_dummies(xreg_test, columns=['month'], drop_first=True)
fcst = StatsForecast(
series_train,
models=[(auto_arima, 12), (seasonal_naive, 12)],
freq='M',
n_jobs=1
)
forecasts = fcst.forecast(12, xreg=xreg_test, level=(80, 95))
forecasts['y_test'] = ap_test
🔨
How to contribute
See CONTRIBUTING.md.
📃
References
- The
auto_arima
model is based (translated) from the R implementation included in the forecast package developed by Rob Hyndman.
✨
Contributors Thanks goes to these wonderful people (emoji key):
fede |
José Morales |
Sugato Ray |
Jeff Tackes |
darinkist |
Alec Helyar |
Dave Hirschfeld |
mergenthaler |
Kin |
Yasslight90 |
asinig |
Philip Gillißen |
This project follows the all-contributors specification. Contributions of any kind welcome!