--- license: mit task_categories: - text-classification tags: - medical - biology --- ## Data Selection & Splitting * **Source:** HRCS 2014, 2018, and 2022 direct award datasets. * **Quality Filtering:** * Only **human-coded** abstracts were included. * Records with abstracts shorter than **75 characters** were removed during preprocessing to ensure the model had sufficient text to learn from. * **Train/Test Split:** The **Test Set** was isolated using only **2022 data** to provide a modern performance benchmark. --- ## Training Data Deduplication To prevent the model from over-fitting on near-identical entries, a robust deduplication pipeline was implemented: 1. **Vectorization:** Character-level **TF-IDF vectors** were generated from training titles using word-boundary character n-grams (length 3–5). 2. **Similarity Analysis:** Near-duplicate titles were identified using a **Cosine Similarity threshold of more than or equal to 0.85**. 3. **Clustering:** Records exceeding this threshold were grouped using a **connected-components graph algorithm**. 4. **Selection:** Only the first occurrence in file order from each group was retained in the training pool. --- ## Leakage Prevention (Train vs. Test) To ensure the test set provides a truly unseen and honest evaluation, the following steps were taken: * **Shared Feature Space:** The TF-IDF vectorizer was fit on the **combined** set of training and test titles. * **Cross-Set Comparison:** Any training record with a **Cosine Similarity threshold of more than or equal to 0.85** to any record in the test set was permanently removed from the training pool. * **Test Set Integrity:** The test set itself was deduplicated using **exact title matching only** (no fuzzy matching applied). > [!IMPORTANT] > **Limitation:** Short, highly generic grant titles (e.g., *"Studentship"*) may have been deduplicated in the training set due to the similarity threshold.