| --- |
| license: mit |
| task_categories: |
| - text-classification |
| tags: |
| - medical |
| - biology |
| --- |
| ## Data Selection & Splitting |
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| * **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. |
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| --- |
|
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| ## Training Data Deduplication |
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| To prevent the model from over-fitting on near-identical entries, a robust deduplication pipeline was implemented: |
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| 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. |
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| --- |
|
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| ## Leakage Prevention (Train vs. Test) |
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| To ensure the test set provides a truly unseen and honest evaluation, the following steps were taken: |
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| * **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). |
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| > [!IMPORTANT] |
| > **Limitation:** Short, highly generic grant titles (e.g., *"Studentship"*) may have been deduplicated in the training set due to the similarity threshold. |