wcep_dense_mean

This is a copy of the [WCEP-10](https://huggingface.co/datasets/ccdv/WCEP-10) dataset, except the input source documents of its `train`, `validation, and `test` splits have been have been replaced by a __dense__ retriever. The retrieval pipeline used:

- __query__: The `summary` field of each example
- __corpus__: The union of all documents in the `train`, `validation` and `test` splits
- __retriever__: [`facebook/contriever-msmarco`](https://huggingface.co/facebook/contriever-msmarco) via [PyTerrier](https://pyterrier.readthedocs.io/en/latest/) with default settings
- __top-k strategy__: `"max"`, i.e. the number of documents retrieved, `k`, is set as the maximum number of documents seen across examples in this dataset, in this case `k==9`

Retrieval results on the `train` set:

| Recall@100 | Rprec | Precision@k | Recall@k |
| ----------- | ----------- | ----------- | ----------- |
| 0.8590 | 0.6490 | 0.6239 | 0.6271 |

Retrieval results on the `validation` set:

| Recall@100 | Rprec | Precision@k | Recall@k |
| ----------- | ----------- | ----------- | ----------- |
| 0.8578 | 0.6326 | 0.6301 | 0.6031 |

Retrieval results on the `test` set:

| Recall@100 | Rprec | Precision@k | Recall@k |
| ----------- | ----------- | ----------- | ----------- |
| 0.8678 | 0.6631 | 0.6564 | 0.6338 |

本数据集为[WCEP-10](https://huggingface.co/datasets/ccdv/WCEP-10)的复刻版本，仅其训练（train）、验证（validation）与测试（test）划分的输入源文档已通过**密集型检索器（dense retriever）**完成替换。所采用的检索流程如下：
- **查询项（query）**：每个样本的`summay`字段
- **语料库（corpus）**：训练、验证与测试划分下的全部文档的并集
- **检索器（retriever）**：通过[PyTerrier](https://pyterrier.readthedocs.io/en/latest/)以默认配置加载的[facebook/contriever-msmarco](https://huggingface.co/facebook/contriever-msmarco)
- **Top-k策略（top-k strategy）**：采用“最大值（max）”策略，即检索文档数`k`被设置为该数据集所有样本中出现的最大文档数，本次场景下`k=9`

训练集检索结果：
| 召回率@100（Recall@100） | R精度（Rprec） | 精确率@k（Precision@k） | 召回率@k（Recall@k） |
| ----------- | ----------- | ----------- | ----------- |
| 0.8590 | 0.6490 | 0.6239 | 0.6271 |

验证集检索结果：
| 召回率@100（Recall@100） | R精度（Rprec） | 精确率@k（Precision@k） | 召回率@k（Recall@k） |
| ----------- | ----------- | ----------- | ----------- |
| 0.8578 | 0.6326 | 0.6301 | 0.6031 |

测试集检索结果：
| 召回率@100（Recall@100） | R精度（Rprec） | 精确率@k（Precision@k） | 召回率@k（Recall@k） |
| ----------- | ----------- | ----------- | ----------- |
| 0.8678 | 0.6631 | 0.6564 | 0.6338 |