ms2_dense_max

This is a copy of the [MS^2](https://huggingface.co/datasets/allenai/mslr2022) dataset, except the input source documents of its `validation` split have been replaced by a __dense__ retriever. The retrieval pipeline used:

- __query__: The `background` field of each example
- __corpus__: The union of all documents in the `train`, `validation` and `test` splits. A document is the concatenation of the `title` and `abstract`.
- __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==25`

Retrieval results on the `train` set:

| Recall@100 | Rprec | Precision@k | Recall@k |
| ----------- | ----------- | ----------- | ----------- |
| 0.4764 | 0.2395 | 0.1932 | 0.2895 |

Retrieval results on the `validation` set:

| Recall@100 | Rprec | Precision@k | Recall@k |
| ----------- | ----------- | ----------- | ----------- |
| 0.4364 | 0.2125 | 0.1823 | 0.2524 |

Retrieval results on the `test` set:

| Recall@100 | Rprec | Precision@k | Recall@k |
| ----------- | ----------- | ----------- | ----------- |
| 0.4481 | 0.2224 | 0.1943 | 0.2567 |

本数据集为[MS^2](https://huggingface.co/datasets/allenai/mslr2022)的复刻版本，仅将其`validation`（验证集）划分的输入源文档替换为**密集型检索器（dense retriever）**获取的文档。所用检索流程如下：
- 查询（query）：每个样本的`background`（背景）字段
- 语料库（corpus）：`train`（训练集）、`validation`（验证集）与`test`（测试集）划分下的所有文档的并集；单篇文档由`title`（标题）与`abstract`（摘要）拼接得到
- 检索器（retriever）：通过[PyTerrier](https://pyterrier.readthedocs.io/en/latest/)框架，采用默认参数配置的[facebook/contriever-msmarco](https://huggingface.co/facebook/contriever-msmarco)模型
- Top-k策略：采用`"max"`模式，即检索文档数`k`取值为该数据集所有样本中所需的最大文档数，本次任务中`k=25`

训练集检索性能：
| 召回率@100（Recall@100） | R准确率（Rprec） | 精确率@k（Precision@k） | 召回率@k（Recall@k） |
| ----------- | ----------- | ----------- | ----------- |
| 0.4764 | 0.2395 | 0.1932 | 0.2895 |

验证集检索性能：
| 召回率@100（Recall@100） | R准确率（Rprec） | 精确率@k（Precision@k） | 召回率@k（Recall@k） |
| ----------- | ----------- | ----------- | ----------- |
| 0.4364 | 0.2125 | 0.1823 | 0.2524 |

测试集检索性能：
| 召回率@100（Recall@100） | R准确率（Rprec） | 精确率@k（Precision@k） | 召回率@k（Recall@k） |
| ----------- | ----------- | ----------- | ----------- |
| 0.4481 | 0.2224 | 0.1943 | 0.2567 |