Anticipating supply chain disruptions before they materialize is a core challenge for firms and policymakers alike. A key difficulty is learning to reason reliably about infrequent, high-impact events from noisy and unstructured inputs - a setting where general-purpose models struggle without task-specific adaptation. We introduce an end-to-end framework that trains LLMs to produce calibrated probabilistic forecasts using realized disruption outcomes as supervision. The resulting model substantially outperforms strong baselines - including GPT-5 - on accuracy, calibration, and precision. We also show that training induces more structured and reliable probabilistic reasoning without explicit prompting. These results suggest a general pathway for training domain-specific forecasting models that produce decision-ready signals. To support transparency we open-source the evaluation dataset used in this study. Dataset: https://huggingface.co/datasets/LightningRodLabs/supply-chain-predictions
Figures & tables
Metric
Training
Test
Time span
1/2022 - 9/2025
10/2025 - 1/2026
# Countries
25
25
# Products
88
88
# Forecasting questions
4,972
452
Event rate (%)
14.9%
10.4%
Table 1: Dataset Summary Statistics
Model
Brier ↓
Brier Skill Score ↑
ECE ↓
Precision ↑
Trained model
0.0791
16.9%
0.0525
0.3478
GPT-5
0.1203
−26.4 %
0.1304
0.0870
GPT-OSS-120B
0.1433
−50.5 %
0.1740
0.1304
Historical Baseline
0.0952
0%
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Table 2: Model performance on the held-out test set. Lower Brier score and ECE indicate better performance, while higher Brier skill score and precision are better.
Figure 1: Aggregate performance on the held-out test set
Figure 2: Reliability diagram on the test set showing empirical disruption rates as a function of predicted disruption probabilities.
Dimension
Pretrained Model
Fine-tuned Model
Structure
Short, largely heuristic reasoning
Multi-step reasoning with explicit intermediate structure
Temporal orientation
Describes recent events
Connects current signals to future outcomes
Quantitative grounding
Rare use of numerical reasoning
Frequent use of thresholds, distributions, and rough calculations
Base rate usage
Implicit or absent
Explicit anchoring to baseline probabilities
Uncertainty handling
Single-pass conclusions
Iterative refinement with intermediate estimates
Use of news
Summarizes salient events
Selectively incorporates signals relevant to disruption risk
Table 3: Systematic differences in reasoning behavior before and after training.
Behavior
Pretrained
Fine-tuned
Base rate anchoring
0.09
0.50
Statistical modeling
0.48
1.00
Explicit forecasting model
0.25
0.96
Evidence → outcome linkage
0.67
0.70
Probabilistic synthesis
0.94
1.00
Uncertainty refinement
0.33
1.00
Table 4: Frequency of reasoning behaviors detected by automated evaluator. Values represent the fraction of responses exhibiting each behavior.
Large language models have achieved significant progress in event forecasting, yet their probability outputs exhibit systematic calibration bias that varies heterogeneously across different domains and question types, undermining the trustworthiness of probabilistic outputs for decision-making under uncertainty. However, existing calibration methods typically correct probability outputs after prediction is complete, without modeling the structural sources of bias within the prediction process itself. To address this challenge, we decompose probabilistic prediction over causal-temporal hypergraphs into three stages, evidence weighting, evidence aggregation, and source fusion, and propose CHAIN, which designs stage-specific mechanisms to mitigate bias at each stage: (i) modulating the temporal decay function by causal topological distance, (ii) aggregating approximately independent causal chains via Noisy-OR after direction-aware deduplication, and (iii) driving adaptive fusion by causal coverage and directional balance. Experimental results on cross-domain forecasting benchmarks show CHAIN outperforms existing methods in expected calibration error, Brier score, and accuracy. Our project is available at https://github.com/QwenQKing/Chain.
Wenjin Liu, Chenxi Wang, Yue Lu +2
Hithink research · Nanyang Technological University
Large language models fine-tuned for forecasting can be accurate yet poorly calibrated, and their chain-of-thought (CoT) reasoning may not faithfully reflect the evidence behind a forecast. We ask whether internal representations offer a more direct window into both. Working with Eternis-Forecaster 8B on OpenForesight, we train representation-pooling probes on intermediate activations and find they achieve substantially better calibration; a result that also holds for GLM-4.7-Flash and GLM-4.5-Air. We then assess CoT faithfulness through evidence ablation and diversionary injection: removing an influential source in the prompt often changes the model's forecast while leaving the reasoning trace untouched. The same probes function as lie detectors: their activations track behavioral shifts far better than the reasoning trace does, and they also predict the direction of change in 84% of cases, including when the CoT conceals the perturbation's influence. Finally, forced answering reveals that forecasts are largely fixed before reasoning begins: a single pre-reasoning pass recovers the committed answer and confidence, and routing questions by the spread of this pre-set answer distribution saves 30-47% of generated tokens, with no loss of accuracy. Together, these results establish probing internal representations as a practical tool for calibrating, auditing, and triaging language model forecasters and reasoning models more broadly.
This study examines the ability of large language models (LLMs) to predict the risk of weather-related forced outages in the distribution grid in a zero-shot framework, without labeled training data. The problem is formulated as a binary severity classification task across three forecast horizons (3h, 6h, 12h), using six years of outage records and high-resolution weather data for a utility service area in central Texas. Four zero-shot LLMs are benchmarked against two supervised classifiers across two input configurations: one using current weather observations and the other using weather forecast data. Results show that supervised models outperform LLMs on macro-F1 and precision, while newer LLM generations achieve competitive scores. Beyond accuracy, LLMs offer complementary strengths in actionable reasoning and geographic scalability, suggesting that combining them with supervised models may be the best practice.