| --- |
| pretty_name: MS MARCO v1 Passage multivector embeddings (ColBERTv2) |
| task_categories: [text-retrieval] |
| tags: [late-interaction, colbert, multivector, msmarco] |
| --- |
| |
| # MS MARCO v1 Passage, ColBERTv2 |
|
|
| Token-level (late-interaction) ColBERTv2 embeddings of the MS MARCO v1 passage collection and the dev/small queries. |
|
|
| ## Source |
| - Collection: MS MARCO v1 passage (`ir_datasets` `msmarco-passage`), 8,841,823 passages |
| - Queries: dev/small, 6,980 queries and 7,437 qrels (`msmarco-passage/dev/small`) |
| - Document order: passage id order (row *i* is pid *i*) |
|
|
| ## Encoding |
| - Model: ColBERTv2 (`colbert-ir/colbertv2.0`, BERT-base-uncased tokenizer) |
| - Documents start with `[CLS]` and the ColBERT `[D]` marker (token id 2) |
| - Queries: always 32 vectors (`[MASK]` expansion, no zero padding) |
| - Vectors: 128-d, L2-normalized |
| - **Not recorded:** exact checkpoint revision, encoding library, document length cap (the longest document has 300 vectors), and whether punctuation was dropped |
|
|
| ## Statistics |
| | | | |
| |---|---| |
| | Token vectors (N) | 597,909,919 | |
| | Avg vectors per document | 67.6 (min 4, max 300) | |
| | Vectors per query | 32 | |
|
|
| ## Files |
| | File | dtype | Shape | Content | |
| |---|---|---|---| |
| | `documents.npy` | uint16 (`<u2`) | `[597909919, 128]` | Raw float16 bit patterns stored as uint16. Read with `.view(np.float16)` | |
| | `doclens.npy` | int32 | `[8841823]` | Vectors per document; `sum == N` | |
| | `token_ids_per_token.npy` | int64 | `[597909919]` | Input token id of each row of `documents.npy` | |
| | `doc_ids.npy` | int64 | `[8841823]` | MS MARCO pid (equals the row index) | |
| | `queries.npy` | float32 | `[6980, 32, 128]` | Query vectors | |
| | `queries_ids.npy` | int64 | `[6980]` | MS MARCO qid of each query | |
|
|
| Document ids are MS MARCO passage ids and equal the row index: row *i* of `doclens.npy` is passage *i*. |
|
|
| `documents.npy` stores float16 values as their raw 16-bit patterns, with dtype uint16. |
| In numpy, read it with `np.load("documents.npy", mmap_mode="r").view(np.float16)`. |
|
|
| ## Relevance judgments |
| The official MS MARCO passage dev/small qrels (`qrels.dev.small.tsv`): 7,437 relevant |
| query-passage pairs over the 6,980 queries, all with relevance 1 (`ir_datasets` `msmarco-passage/dev/small`). |
| Standard metric: MRR@10 (`RR@10` in `ir_measures`). |
|
|
