📚 Using Shapley Interactions to Understand How Models Use Structure

This repository provides code and scripts to reproduce experiments from the paper:

“Using Shapley Interactions to Understand How Models Use Structure”
Divyansh Singhvi, Diganta Misra, Andrej Erkelens, Raghav Jain, Isabel Papadimitriou, Naomi Saphra
arXiv:2403.13106v2 · ACL 2025 Paper

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📝 Overview

Modern language and speech models learn rich hidden structures about syntax, semantics, and phonetics.

This repository shows how to use the Shapley-Taylor Interaction Index (STII) to quantify pairwise interactions:

• Text models: How do pairs of tokens interact beyond their individual effects?
• Speech models: How do acoustic frames interact near phoneme boundaries?

By doing so, you can test:

• How well models encode syntactic tree structures
• How they handle multiword expressions
• How speech models reflect phonetic coarticulation

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📂 Repository Structure

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🧮 How It Works

✅ STII for Text (ExperimentRunner):

• Load tagged sentences with multiword expressions (MWEs) and syntactic trees
• For token pairs:
  • Compute logits for 4 contexts: AB, A, B, φ (none)
  • Interaction = (AB - A - B + φ) and normalize by (φ) norms
• Analyze how interaction varies with:
  • Linear distance
  • Syntactic distance
  • Whether tokens belong to a strong or weak MWE

✅ STII for Speech (SpeechSTIIExperimentRunner):

• Load audio and phoneme time alignments
• Mask 20ms waveform slices to simulate ablations
• Compare interaction:
  • Consonant-vowel vs consonant-consonant
  • By manner of articulation (how vowel-like a consonant is)
  • The methodology is same for both Speech and Text

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🚀 How to Run

1️⃣ Install Environment

Create the environment using conda.yaml:

conda env create -f conda.yaml -n shapley_llm
conda activate shapley_llm

2️⃣ Run Text Experiments

1. Generate Language Data

cd language/mwe_tagger
./run_sr_pipeline.sh <model_name> <model_name>

model_names : ['gpt2', 'bert']

Places the MWE tagger outputs at (bert_bert.pkl_* or gpt_gpt.pkl_*) in language/mwe_tagger/ Then run:

python language/language_runner.py

3️⃣ Run Speech Experiments

Add audio files to speech_data/mfa_inp_new/ and phoneme CSVs to speech_data/extracted_phonemes/. Results are written to speech_data/stii_outputs_fix/. To generate the files and csv use files at speech/data_utils/

python speech/speech_runner.py