LatentTSF (ICML 2026)

Official PyTorch implementation of From Observations to States: Latent Time Series Forecasting (ICML 2026).

Authors: Jie Yang, Yifan Hu, Yuante Li, Kexin Zhang, Kaize Ding, Philip S. Yu

TL;DR. Standard time-series forecasters predict raw observations, but their hidden representations exhibit Latent Chaos — temporally disordered states that hurt long-horizon stability. LatentTSF instead trains the forecaster to predict the latent states of a frozen pretrained autoencoder, using a joint latent-space prediction and alignment loss (Eq. 5 in the paper). An optional observation-space perceptual loss is available but disabled by default. The objective implicitly maximizes the mutual information between predicted and ground-truth latent states.

Overview

A pretrained autoencoder $(\mathcal{E}, \mathcal{D})$ is frozen, and a forecaster $f_\theta$ is trained entirely in its latent space:

$$ X \xrightarrow{\mathcal{E}} Z_X \xrightarrow{f_\theta} \hat{Z}_Y \xrightarrow{\mathcal{D}} \hat{Y}, \qquad Y \xrightarrow{\mathcal{E}} Z_Y $$

The training objective (paper Eq. 5) combines a latent-space prediction loss and an alignment loss, both computed in the latent space:

$$ \mathcal{L}_{\text{Pred}} = \lVert Z_Y - \hat{Z}_Y \rVert_F^{2} $$

$$ \mathcal{L}_{\text{Align}} = 1 - \frac{\langle Z_Y, \hat{Z}_Y \rangle_F}{\lVert Z_Y \rVert_F \cdot \lVert \hat{Z}_Y \rVert_F} $$

$$ \mathcal{L}_{\text{total}} = \alpha \cdot \mathcal{L}_{\text{Pred}} + \beta \cdot \mathcal{L}_{\text{Align}} $$

Only $f_\theta$ is updated during training. The paper's chosen defaults (Sec. 5.3.2) are $\alpha = 10$ (Pred Weight) and $\beta = 15$ (Align Weight); these are the defaults in this repo. An optional observation-space perceptual loss $\mathcal{L}_{\text{Perc}} = \mathrm{MSE}(\mathcal{D}(\hat{Z}_Y), Y)$ is implemented (--perceptual_weight) but disabled by default, matching the paper's final recipe (Sec. 5.3.1).

Requirements

• Python ≥3.8
• PyTorch (install separately to match your CUDA version, e.g. pip install torch --index-url https://download.pytorch.org/whl/cu121 — see https://pytorch.org/get-started/locally/)
• All other dependencies: pip install -r requirements.txt

requirements.txt mirrors the upstream Time-Series-Library list (so all baseline models in models/ can be loaded), plus wandb for experiment logging. torch is intentionally not pinned.

Setup

Download the benchmark datasets to ./dataset/ (created on first run):

python download_datasets.py

This pulls ETTh1/2, ETTm1/2, weather, electricity, traffic, exchange_rate, and solar_energy from HuggingFace into ./dataset/. Users in mainland China can speed it up by exporting a mirror endpoint before running:

export HF_ENDPOINT=https://hf-mirror.com
python download_datasets.py

Quick Start

1. Reproduce with the pretrained AE

The repository ships with 9 pretrained autoencoders (one per benchmark). Two entry points are provided — both share the same per-dataset configs and the paper's loss recipe ($\alpha=10$, $\beta=15$, no perceptual / reconstruction loss).

Single example — run_train.sh. Just edit the three variables dataset / model / pred_len at the top, then:

bash run_train.sh

The default reproduces the DLinear / ETTh1 / pred_len=96 cell of paper Table 1, using checkpoints/AutoEncoder_MLP_MAE_ETTh1_..._sl24_..._0/checkpoint.pth. The matching checkpoint paths for other datasets are in the Pretrained AE Checkpoints table — run_train.sh resolves them automatically from the per-dataset config table.

Full sweep — run_train_all.sh. Set datasets / models / pred_lens (space-separated lists) at the top, then:

bash run_train_all.sh

The defaults sweep all 9 datasets × DLinear × {96, 192, 336, 720} = 36 runs and write metrics to result.csv / result/result.txt. Missing AE checkpoints cause the affected dataset to be skipped (warning) rather than aborting the whole sweep. Set delete_checkpoint=1 at the top to remove each run's checkpoint after testing.

2. Original (baseline) mode — no autoencoder

Drop --use_latent and the AE arguments to train any model directly on the raw signal (this is the standard TSLib training path). See my_train.py --help for the full argument list, or the inline comments in run_train.sh.

3. Train your own autoencoder

If you want to retrain the AE from scratch (e.g. a different seq_len or d_model):

bash run_ae.sh

The default trains the ETTh1 AE. To train a different one (or all 9 at once), edit the datasets variable at the top of run_ae.sh — per-dataset d_model / d_ff / learning_rate / batch_size / des are already wired in and match the checkpoint table below.

Pretrained AE Checkpoints

The ./checkpoints/ directory ships with the 9 pretrained MLP autoencoders used in the paper. All AEs are trained with seq_len=24, ae_type=MLP, ae_loss=MAE, lradj=0.

Dataset	enc_in	d_model	d_ff	AE training config	Checkpoint folder
ETTh1	7	32	64	lr=0.0005, bs=32, ep=500	AutoEncoder_MLP_MAE_ETTh1_AE_ETTh1_ftM_sl24_dm32_dff64_lradj0_Exp-sl24-lr0.0005-500-32bs_0
ETTh2	7	64	128	lr=0.0005, bs=32, ep=500	AutoEncoder_MLP_MAE_ETTh2_AE_ETTh2_ftM_sl24_dm64_dff128_lradj0_Exp-sl24-lr0.0005-500-32bs_0
ETTm1	7	32	64	lr=0.0005, bs=32, ep=500	AutoEncoder_MLP_MAE_ETTm1_AE_ETTm1_ftM_sl24_dm32_dff64_lradj0_Exp-sl24-lr0.0005-500-32bs_0
ETTm2	7	64	128	lr=0.0005, bs=32, ep=500	AutoEncoder_MLP_MAE_ETTm2_AE_ETTm2_ftM_sl24_dm64_dff128_lradj0_Exp-sl24-lr0.0005-500-32bs_0
exchange_rate	8	128	256	lr=0.0005, bs=32, ep=500	AutoEncoder_MLP_MAE_exchange_rate_AE_custom_ftM_sl24_dm128_dff256_lradj0_Exp-sl24-lr0.0005-500-32bs_0
weather	21	64	128	lr=0.0005, bs=32, ep=500	AutoEncoder_MLP_MAE_weather_AE_custom_ftM_sl24_dm64_dff128_lradj0_Exp-sl24-lr0.0005-500-32bs_0
electricity	321	512	1024	lr=0.0001, bs=16, ep=500	AutoEncoder_MLP_MAE_electricity_AE_custom_ftM_sl24_dm512_dff1024_lradj0_Exp-lr0.0001-500-16bs_0
traffic	862	512	1024	lr=0.0001, bs=16, ep=500	AutoEncoder_MLP_MAE_traffic_AE_custom_ftM_sl24_dm512_dff1024_lradj0_Exp-lr0.0001-500-16bs_0
Solar	137	256	512	lr=0.0005, bs=32, ep=500	AutoEncoder_MLP_MAE_Solar_AE_Solar_ftM_sl24_dm256_dff512_lradj0_Exp-sl24-lr0.0005-500-32bs_0

Pass the corresponding folder's checkpoint.pth as --autoencoder_path when running my_train.py with --use_latent. To retrain an AE from scratch, see run_ae.sh (defaults match the ETTh1 config above).

Repository Structure

LatentTSF/
├── my_train.py             # Latent-space forecaster training (main entry)
├── my_AE.py                # MLP / CNN AE + training
├── my_temporal_AE.py       # Temporal AE (seq_len dimension)
├── my_MAE.py               # Masked autoencoder (optional encoder type)
├── my_utils.py             # Args, valid/test loops, CSV logging
├── RevIN.py                # RevIN normalization
├── run_train.sh            # Single-example training (one dataset × model × horizon)
├── run_train_all.sh        # Full sweep training (lists of datasets × models × horizons)
├── run_ae.sh               # Train AE from scratch (defaults = ETTh1 paper config)
├── run.py                  # Standard TSLib entry point (baselines, etc.)
├── download_datasets.py    # Fetch benchmarks from HuggingFace
├── checkpoints/            # 9 pretrained AEs (see table above)
├── data_provider/          # Dataset loaders
├── exp/                    # TSLib experiment scaffolding
├── layers/                 # Reusable layers
├── models/                 # Forecasting backbones (DLinear, iTransformer, ...)
└── utils/                  # Metrics, early stopping, DTW, etc.

Notes on optional flags

• For latent mode, set --label_len 0.
• Pass --result_csv results.csv to log MSE/MAE per run; --result_txt result/result.txt to append a per-run text summary.
• Loss-weight flags (defaults match paper Sec. 5.3.2):
  • --mse_weight 10.0 — $\alpha$ (Pred Weight, paper main recipe)
  • --cosine_weight 15.0 — $\beta$ (Align Weight, paper main recipe)
  • --perceptual_weight 0.0 — observation-space MSE on decoded forecast; off by default per paper Sec. 5.3.1, set $>0$ to enable as an ablation
  • --reconstruction_weight 0.0 — extra L1 consistency $\lVert\mathcal{D}(Z_Y) - Y\rVert_1$; not in paper, off by default
• --save_visual + --visual_interval 20 save per-batch prediction-vs-truth PDFs to result/<setting>/.
• ae_type accepts MLP, MLP_REVIN, CNN, Temporal, TemporalCNN.
• encoder_type=MAE (Masked Autoencoder) is supported in code but not used in the paper — the 9 shipped checkpoints are all standard MLP autoencoders.

Citation

If you find this work useful, please cite:

@article{yang2026observations,
  title={From Observations to States: Latent Time Series Forecasting},
  author={Yang, Jie and Hu, Yifan and Li, Yuante and Zhang, Kexin and Ding, Kaize and Yu, Philip S},
  journal={arXiv preprint arXiv:2602.00297},
  year={2026}
}

Acknowledgments

This codebase builds on Time-Series-Library (THUML). We thank the authors for their open implementation of standard forecasting baselines and benchmark loaders.

License

This project is released under the MIT License.

This repository also incorporates code from Time-Series-Library and N-BEATS. See NOTICE.md for full attribution. Note: utils/losses.py, utils/m4_summary.py, and data_provider/m4.py are licensed under CC BY-NC 4.0 (non-commercial only) by Element AI Inc., and are NOT covered by the MIT license — replace or remove them if you need to use this codebase commercially.

Star History