英文

⚠️ 该模型已弃用。请勿使用该模型,因为它产生的句子嵌入质量较低。您可以在此处找到推荐的句子嵌入模型:点击查看

sentence-transformers/nli-roberta-base

这是一个句子嵌入模型:它将句子和段落映射到一个768维的稠密向量空间,可用于聚类或语义搜索等任务。

用法(Sentence-Transformers)

安装了该模型库

  • 之后,可轻松使用该模型:

    pip install -U sentence-transformers
    

    然后您可以像这样使用该模型:

    from sentence_transformers import SentenceTransformer
    sentences = ["This is an example sentence", "Each sentence is converted"]
    
    model = SentenceTransformer('sentence-transformers/nli-roberta-base')
    embeddings = model.encode(sentences)
    print(embeddings)
    

    用法(HuggingFace Transformers)

    如果没有安装该模型库,可按照以下步骤使用该模型:首先,将输入传递给Transformer模型,然后在上下文化的词嵌入之上应用正确的池化操作。

    from transformers import AutoTokenizer, AutoModel
    import torch
    
    
    #Mean Pooling - Take attention mask into account for correct averaging
    def mean_pooling(model_output, attention_mask):
        token_embeddings = model_output[0] #First element of model_output contains all token embeddings
        input_mask_expanded = attention_mask.unsqueeze(-1).expand(token_embeddings.size()).float()
        return torch.sum(token_embeddings * input_mask_expanded, 1) / torch.clamp(input_mask_expanded.sum(1), min=1e-9)
    
    
    # Sentences we want sentence embeddings for
    sentences = ['This is an example sentence', 'Each sentence is converted']
    
    # Load model from HuggingFace Hub
    tokenizer = AutoTokenizer.from_pretrained('sentence-transformers/nli-roberta-base')
    model = AutoModel.from_pretrained('sentence-transformers/nli-roberta-base')
    
    # Tokenize sentences
    encoded_input = tokenizer(sentences, padding=True, truncation=True, return_tensors='pt')
    
    # Compute token embeddings
    with torch.no_grad():
        model_output = model(**encoded_input)
    
    # Perform pooling. In this case, max pooling.
    sentence_embeddings = mean_pooling(model_output, encoded_input['attention_mask'])
    
    print("Sentence embeddings:")
    print(sentence_embeddings)
    

    评估结果

    要自动评估该模型,请参阅句子嵌入基准

    完整的模型架构

    SentenceTransformer(
      (0): Transformer({'max_seq_length': 128, 'do_lower_case': True}) with Transformer model: RobertaModel 
      (1): Pooling({'word_embedding_dimension': 768, 'pooling_mode_cls_token': False, 'pooling_mode_mean_tokens': True, 'pooling_mode_max_tokens': False, 'pooling_mode_mean_sqrt_len_tokens': False})
    )
    

    引用与作者

    该模型由 sentence-transformers 训练。

    如果您觉得该模型有帮助,请随意引用我们的出版物: Sentence-BERT: Sentence Embeddings using Siamese BERT-Networks

    @inproceedings{reimers-2019-sentence-bert,
        title = "Sentence-BERT: Sentence Embeddings using Siamese BERT-Networks",
        author = "Reimers, Nils and Gurevych, Iryna",
        booktitle = "Proceedings of the 2019 Conference on Empirical Methods in Natural Language Processing",
        month = "11",
        year = "2019",
        publisher = "Association for Computational Linguistics",
        url = "http://arxiv.org/abs/1908.10084",
    }