--- language: - uk license: cc-by-nc-sa-4.0 size_categories: - 1K 2024) via E5-large | 116 | ## Key Findings 1. **Co-citation predictability decays 33--47% over 12 years** (Mann-Kendall p < 0.005) 2. **Decay is non-uniform**: criminal procedure maintains stable co-citation patterns (MRR ~0.40); civil law degrades from 0.35 to 0.15 3. **Neither BM25 nor dense retrieval (E5-large, BGE-M3) escapes temporal degradation** 4. **Sliding-window mitigation improves MRR by 3--28%** over cumulative indexing ## Evaluation Protocol **Leave-one-out on the full bipartite citation graph:** For each court decision with cited articles {a1, ..., an}: 1. Mask each article ai in turn 2. Score all candidate articles using remaining citations as seed 3. Compute rank of masked article among non-seed candidates ### Baselines (2024 snapshot) | Method | Hit@10 | MRR | |--------|:------:|:---:| | Adamic-Adar | 0.545 | 0.272 | | Common Neighbors | 0.534 | 0.266 | | E5-large (dense) | 0.192 | 0.090 | | BGE-M3 (dense) | 0.240 | 0.096 | | BM25 (lexical) | 0.082 | 0.047 | | Degree Baseline | 0.111 | 0.059 | ### Difficulty Stratification | Bin | Articles | MRR (AA) | |-----|:--------:|:--------:| | Hub (>100K cites) | 21 | 0.536 | | High (10K--100K) | 354 | 0.274 | | Mid (1K--10K) | 864 | 0.074 | | Low (100--1K) | 1,689 | 0.020 | | Rare (<100) | 739 | 0.010 | ## Usage ```python from datasets import load_dataset # Per-article performance (2024) articles = load_dataset("overthelex/ua-statute-retrieval", "article_performance", split="train") print(articles.to_pandas()[["target_article", "degree", "mrr_aa"]].head(10)) # Temporal ablation (Fig 2 in paper) ablation = load_dataset("overthelex/ua-statute-retrieval", "ablation_comparison", split="train") print(ablation.to_pandas()) # Sliding-window mitigation (Table 6 in paper) sw = load_dataset("overthelex/ua-statute-retrieval", "sliding_window", split="train") print(sw.to_pandas().pivot(index="eval_year", columns="window_label", values="mrr_aa")) # Embedding drift (Fig 9 in paper) drift = load_dataset("overthelex/ua-statute-retrieval", "embedding_drift", split="train") print(drift.to_pandas().groupby("law_number")["drift"].mean().sort_values(ascending=False)) ``` ## Citation ```bibtex @article{ovcharov2025statute, title={Temporal Decay of Co-Citation Predictability: A 20-Year Statute Retrieval Benchmark from 396M Ukrainian Court Citations}, author={Ovcharov, Volodymyr}, year={2025} } ``` ## Source Data Derived from the Ukrainian Unified State Register of Court Decisions (EDRSR, https://reyestr.court.gov.ua). Raw citation data (502M records) remains proprietary; the co-citation graph is available separately at [overthelex/ua-court-citation-graph](https://huggingface.co/datasets/overthelex/ua-court-citation-graph). ## Related Datasets - [overthelex/ua-court-citation-graph](https://huggingface.co/datasets/overthelex/ua-court-citation-graph) -- Co-citation graph (99.5M decisions) - [overthelex/ukrainian-court-decisions](https://huggingface.co/datasets/overthelex/ukrainian-court-decisions) -- Court decision metadata