Chronocept Baseline Models

Publication: Chronocept: Instilling a Sense of Time in Machines
Authors: Krish Goel, Sanskar Pandey, KS Mahadevan, Harsh Kumar, and Vishesh Khadaria

Dataset: huggingface/krishgoel/chronocept

This repository contains baseline implementations for Chronocept, the world's first benchmark for modeling validity of textual information as continuous probability distributions over time. The models predict three parameters (location ξ, scale ω, skewness α) that characterize the temporal relevance of textual information using a skew-normal distribution, over a logarithmically transformed time axis.

DataLoader Implementation

The DataLoader class utils/dataloader.py is used to load and preprocess the data. It supports multiple embedding methods and data splits.

Parameters

• benchmark (Literal["benchmark_1", "benchmark_2"]):
  Benchmark identifier.

• split ("train" | "validation" | "test" | List[str] | None, default=None):
  Which data splits to load. If None, all splits are loaded.

• embedding (str, default="bert_cls"):
  Embedding method:

  • "bert_cls": CLS token from BERT.
  • "bert_full": Mean pooling over BERT tokens.
  • "bert_sequential": Full token sequence from BERT.
  • "sbert": Sentence-BERT (all-MiniLM-L6-v2).
  • "tfidf": TF-IDF (max 512 features).
  • "glove": Averaged GloVE embeddings.

• max_len (int, default=128):
  Maximum sequence length for BERT-based tokenization.

• include_axes (bool, default=False):
  Whether to include the 8 temporal axes with the parent_text. Final input = parent embedding + flattened axes.

• shuffle_axes (bool, default=False):
  Shuffle the 8 axes per sample (only if include_axes=True).

• normalization ("zscore" | "minmax" | "none" | None, default="zscore"):
  Target value normalization:

  • "zscore": Zero mean, unit variance.
  • "minmax": Scale to [0, 1].
  • "none" or None: No normalization.

• log_scale (float, default=1.1):
  Base for logarithmic transformation of target values. If set, log(y) / log(log_scale) is applied.

Usage Example

from utils import DataLoader

# Initialize loader
dl = DataLoader(
    benchmark="benchmark_1",
    split=None,  # Loads all splits
    embedding="bert_cls",
    max_len=128,
    include_axes=True,
    normalization="zscore"
)

# Preprocess data
data = dl.preprocess()  # Returns dict with all splits if split=None
X_train, y_train = data["train"]
X_valid, y_valid = data["validation"]
X_test, y_test = data["test"]

Performance Statistics

Benchmark I (1254 samples)

Baseline	MSE	MAE	R²	NLL	Spearman
LR	1.3610	0.9179	-0.3610	1.5730	0.2338
XGB	0.8884	0.7424	0.1116	1.3598	0.2940
SVR	0.9067	0.7529	0.0933	1.3700	0.3281
FFNN	0.8763	0.7284	0.1237	1.3529	0.3543
Bi-LSTM	0.9203	0.7571	0.0797	1.3774	0.2367
BERT	145.8611	6.7570	-0.0090	3.9103	-0.0485

Benchmark II (524 samples)

Baseline	MSE	MAE	R²	NLL	Spearman
LR	1.1009	0.8361	-0.1009	1.4670	0.3279
XGB	0.9580	0.8011	0.0420	1.3975	0.2331
SVR	0.8889	0.7740	0.1111	1.3601	0.3293
FFNN	0.8715	0.7583	0.1285	1.3502	0.3437
Bi-LSTM	0.8702	0.7646	0.1298	1.3494	0.3535
BERT	68.1507	4.6741	-0.1122	3.5299	-0.2407

Note: All metrics are computed on Z-score normalized targets on the test set.

License

This project is licensed under the MIT License. See the LICENSE file for details.

Citation

If you use Chronocept in your work, please cite the following:

@misc{goel2025chronocept,
    title={Chronocept: Instilling a Sense of Time in Machines}, 
    author={Krish Goel and Sanskar Pandey and KS Mahadevan and Harsh Kumar and Vishesh Khadaria},
    year={2025},
    eprint={2505.07637},
    archivePrefix={arXiv},
    primaryClass={cs.CL},
    url={https://arxiv.org/abs/2505.07637}, 
}