Splinter¶
Overview¶
The Splinter model was proposed in Few-Shot Question Answering by Pretraining Span Selection by Ori Ram, Yuval Kirstain, Jonathan Berant, Amir Globerson, Omer Levy. Splinter is an encoder-only transformer (similar to BERT) pretrained using the recurring span selection task on a large corpus comprising Wikipedia and the Toronto Book Corpus.
The abstract from the paper is the following:
In several question answering benchmarks, pretrained models have reached human parity through fine-tuning on an order of 100,000 annotated questions and answers. We explore the more realistic few-shot setting, where only a few hundred training examples are available, and observe that standard models perform poorly, highlighting the discrepancy between current pretraining objectives and question answering. We propose a new pretraining scheme tailored for question answering: recurring span selection. Given a passage with multiple sets of recurring spans, we mask in each set all recurring spans but one, and ask the model to select the correct span in the passage for each masked span. Masked spans are replaced with a special token, viewed as a question representation, that is later used during fine-tuning to select the answer span. The resulting model obtains surprisingly good results on multiple benchmarks (e.g., 72.7 F1 on SQuAD with only 128 training examples), while maintaining competitive performance in the high-resource setting.
Tips:
Splinter was trained to predict answers spans conditioned on a special [QUESTION] token. These tokens contextualize to question representations which are used to predict the answers. This layer is called QASS, and is the default behaviour in the
SplinterForQuestionAnswering
class. Therefore:Use
SplinterTokenizer
(rather thanBertTokenizer
), as it already contains this special token. Also, its default behavior is to use this token when two sequences are given (for example, in the run_qa.py script).If you plan on using Splinter outside run_qa.py, please keep in mind the question token - it might be important for the success of your model, especially in a few-shot setting.
Please note there are two different checkpoints for each size of Splinter. Both are basically the same, except that one also has the pretrained wights of the QASS layer (tau/splinter-base-qass and tau/splinter-large-qass) and one doesn’t (tau/splinter-base and tau/splinter-large). This is done to support randomly initializing this layer at fine-tuning, as it is shown to yield better results for some cases in the paper.
This model was contributed by yuvalkirstain and oriram. The original code can be found here.
SplinterConfig¶
-
class
transformers.
SplinterConfig
(vocab_size=30522, hidden_size=768, num_hidden_layers=12, num_attention_heads=12, intermediate_size=3072, hidden_act='gelu', hidden_dropout_prob=0.1, attention_probs_dropout_prob=0.1, max_position_embeddings=512, type_vocab_size=2, initializer_range=0.02, layer_norm_eps=1e-12, use_cache=True, pad_token_id=0, question_token_id=104, **kwargs)[source]¶ This is the configuration class to store the configuration of a
SplinterModel
. It is used to instantiate an Splinter model according to the specified arguments, defining the model architecture. Instantiating a configuration with the defaults will yield a similar configuration to that of the Splinter tau/splinter-base architecture.Configuration objects inherit from
PretrainedConfig
and can be used to control the model outputs. Read the documentation fromPretrainedConfig
for more information.- Parameters
vocab_size (
int
, optional, defaults to 30522) – Vocabulary size of the Splinter model. Defines the number of different tokens that can be represented by theinputs_ids
passed when callingSplinterModel
.hidden_size (
int
, optional, defaults to 768) – Dimension of the encoder layers and the pooler layer.num_hidden_layers (
int
, optional, defaults to 12) – Number of hidden layers in the Transformer encoder.num_attention_heads (
int
, optional, defaults to 12) – Number of attention heads for each attention layer in the Transformer encoder.intermediate_size (
int
, optional, defaults to 3072) – Dimension of the “intermediate” (i.e., feed-forward) layer in the Transformer encoder.hidden_act (
str
orfunction
, optional, defaults to"gelu"
) – The non-linear activation function (function or string) in the encoder and pooler. If string,"gelu"
,"relu"
,"selu"
and"gelu_new"
are supported.hidden_dropout_prob (
float
, optional, defaults to 0.1) – The dropout probabilitiy for all fully connected layers in the embeddings, encoder, and pooler.attention_probs_dropout_prob (
float
, optional, defaults to 0.1) – The dropout ratio for the attention probabilities.max_position_embeddings (
int
, optional, defaults to 512) – The maximum sequence length that this model might ever be used with. Typically set this to something large just in case (e.g., 512 or 1024 or 2048).type_vocab_size (
int
, optional, defaults to 2) – The vocabulary size of thetoken_type_ids
passed when callingSplinterModel
.initializer_range (
float
, optional, defaults to 0.02) – The standard deviation of the truncated_normal_initializer for initializing all weight matrices.layer_norm_eps (
float
, optional, defaults to 1e-12) – The epsilon used by the layer normalization layers.use_cache (
bool
, optional, defaults toTrue
) – Whether or not the model should return the last key/values attentions (not used by all models). Only relevant ifconfig.is_decoder=True
.gradient_checkpointing (
bool
, optional, defaults toFalse
) – IfTrue
, use gradient checkpointing to save memory at the expense of slower backward pass.question_token_id (
int
, optional, defaults to 104) – The id of the[QUESTION]
token.Example:: –
>>> from transformers import SplinterModel, SplinterConfig
>>> # Initializing a Splinter tau/splinter-base style configuration >>> configuration = SplinterConfig()
>>> # Initializing a model from the tau/splinter-base style configuration >>> model = SplinterModel(configuration)
>>> # Accessing the model configuration >>> configuration = model.config
SplinterTokenizer¶
-
class
transformers.
SplinterTokenizer
(vocab_file, do_lower_case=True, do_basic_tokenize=True, never_split=None, unk_token='[UNK]', sep_token='[SEP]', pad_token='[PAD]', cls_token='[CLS]', mask_token='[MASK]', question_token='[QUESTION]', tokenize_chinese_chars=True, strip_accents=None, **kwargs)[source]¶ Construct a Splinter tokenizer. Based on WordPiece.
This tokenizer inherits from
PreTrainedTokenizer
which contains most of the main methods. Users should refer to this superclass for more information regarding those methods.- Parameters
vocab_file (
str
) – File containing the vocabulary.do_lower_case (
bool
, optional, defaults toTrue
) – Whether or not to lowercase the input when tokenizing.do_basic_tokenize (
bool
, optional, defaults toTrue
) – Whether or not to do basic tokenization before WordPiece.never_split (
Iterable
, optional) – Collection of tokens which will never be split during tokenization. Only has an effect whendo_basic_tokenize=True
unk_token (
str
, optional, defaults to"[UNK]"
) – The unknown token. A token that is not in the vocabulary cannot be converted to an ID and is set to be this token instead.sep_token (
str
, optional, defaults to"[SEP]"
) – The separator token, which is used when building a sequence from multiple sequences, e.g. two sequences for sequence classification or for a text and a question for question answering. It is also used as the last token of a sequence built with special tokens.pad_token (
str
, optional, defaults to"[PAD]"
) – The token used for padding, for example when batching sequences of different lengths.cls_token (
str
, optional, defaults to"[CLS]"
) – The classifier token which is used when doing sequence classification (classification of the whole sequence instead of per-token classification). It is the first token of the sequence when built with special tokens.mask_token (
str
, optional, defaults to"[MASK]"
) – The token used for masking values. This is the token used when training this model with masked language modeling. This is the token which the model will try to predict.question_token (
str
, optional, defaults to"[QUESTION]"
) – The token used for constructing question representations.tokenize_chinese_chars (
bool
, optional, defaults toTrue
) –Whether or not to tokenize Chinese characters.
This should likely be deactivated for Japanese (see this issue).
strip_accents – (
bool
, optional): Whether or not to strip all accents. If this option is not specified, then it will be determined by the value forlowercase
(as in the original BERT).
-
build_inputs_with_special_tokens
(token_ids_0: List[int], token_ids_1: Optional[List[int]] = None) → List[int][source]¶ Build model inputs from a pair of sequence for question answering tasks by concatenating and adding special tokens. A Splinter sequence has the following format:
single sequence:
[CLS] X [SEP]
pair of sequences for question answering:
[CLS] question_tokens [QUESTION] . [SEP] context_tokens [SEP]
- Parameters
token_ids_0 (
List[int]
) – The question token IDs if pad_on_right, else context tokens IDstoken_ids_1 (
List[int]
, optional) – The context token IDs if pad_on_right, else question token IDs
- Returns
List of input IDs with the appropriate special tokens.
- Return type
List[int]
-
create_token_type_ids_from_sequences
(token_ids_0: List[int], token_ids_1: Optional[List[int]] = None) → List[int][source]¶ Create the token type IDs corresponding to the sequences passed. What are token type IDs?
Should be overridden in a subclass if the model has a special way of building those.
- Parameters
token_ids_0 (
List[int]
) – The first tokenized sequence.token_ids_1 (
List[int]
, optional) – The second tokenized sequence.
- Returns
The token type ids.
- Return type
List[int]
-
get_special_tokens_mask
(token_ids_0: List[int], token_ids_1: Optional[List[int]] = None, already_has_special_tokens: bool = False) → List[int][source]¶ Retrieve sequence ids from a token list that has no special tokens added. This method is called when adding special tokens using the tokenizer
prepare_for_model
method.- Parameters
token_ids_0 (
List[int]
) – List of IDs.token_ids_1 (
List[int]
, optional) – Optional second list of IDs for sequence pairs.already_has_special_tokens (
bool
, optional, defaults toFalse
) – Whether or not the token list is already formatted with special tokens for the model.
- Returns
A list of integers in the range [0, 1]: 1 for a special token, 0 for a sequence token.
- Return type
List[int]
-
save_vocabulary
(save_directory: str, filename_prefix: Optional[str] = None) → Tuple[str][source]¶ Save only the vocabulary of the tokenizer (vocabulary + added tokens).
This method won’t save the configuration and special token mappings of the tokenizer. Use
_save_pretrained()
to save the whole state of the tokenizer.- Parameters
save_directory (
str
) – The directory in which to save the vocabulary.filename_prefix (
str
, optional) – An optional prefix to add to the named of the saved files.
- Returns
Paths to the files saved.
- Return type
Tuple(str)
SplinterTokenizerFast¶
-
class
transformers.
SplinterTokenizerFast
(vocab_file=None, tokenizer_file=None, do_lower_case=True, unk_token='[UNK]', sep_token='[SEP]', pad_token='[PAD]', cls_token='[CLS]', mask_token='[MASK]', question_token='[QUESTION]', tokenize_chinese_chars=True, strip_accents=None, **kwargs)[source]¶ Construct a “fast” Splinter tokenizer (backed by HuggingFace’s tokenizers library). Based on WordPiece.
This tokenizer inherits from
PreTrainedTokenizerFast
which contains most of the main methods. Users should refer to this superclass for more information regarding those methods.- Parameters
vocab_file (
str
) – File containing the vocabulary.do_lower_case (
bool
, optional, defaults toTrue
) – Whether or not to lowercase the input when tokenizing.unk_token (
str
, optional, defaults to"[UNK]"
) – The unknown token. A token that is not in the vocabulary cannot be converted to an ID and is set to be this token instead.sep_token (
str
, optional, defaults to"[SEP]"
) – The separator token, which is used when building a sequence from multiple sequences, e.g. two sequences for sequence classification or for a text and a question for question answering. It is also used as the last token of a sequence built with special tokens.pad_token (
str
, optional, defaults to"[PAD]"
) – The token used for padding, for example when batching sequences of different lengths.cls_token (
str
, optional, defaults to"[CLS]"
) – The classifier token which is used when doing sequence classification (classification of the whole sequence instead of per-token classification). It is the first token of the sequence when built with special tokens.mask_token (
str
, optional, defaults to"[MASK]"
) – The token used for masking values. This is the token used when training this model with masked language modeling. This is the token which the model will try to predict.question_token (
str
, optional, defaults to"[QUESTION]"
) – The token used for constructing question representations.clean_text (
bool
, optional, defaults toTrue
) – Whether or not to clean the text before tokenization by removing any control characters and replacing all whitespaces by the classic one.tokenize_chinese_chars (
bool
, optional, defaults toTrue
) – Whether or not to tokenize Chinese characters. This should likely be deactivated for Japanese (see this issue).strip_accents – (
bool
, optional): Whether or not to strip all accents. If this option is not specified, then it will be determined by the value forlowercase
(as in the original BERT).wordpieces_prefix – (
str
, optional, defaults to"##"
): The prefix for subwords.
-
build_inputs_with_special_tokens
(token_ids_0: List[int], token_ids_1: Optional[List[int]] = None) → List[int][source]¶ Build model inputs from a pair of sequence for question answering tasks by concatenating and adding special tokens. A Splinter sequence has the following format:
single sequence:
[CLS] X [SEP]
pair of sequences for question answering:
[CLS] question_tokens [QUESTION] . [SEP] context_tokens [SEP]
- Parameters
token_ids_0 (
List[int]
) – The question token IDs if pad_on_right, else context tokens IDstoken_ids_1 (
List[int]
, optional) – The context token IDs if pad_on_right, else question token IDs
- Returns
List of input IDs with the appropriate special tokens.
- Return type
List[int]
-
create_token_type_ids_from_sequences
(token_ids_0: List[int], token_ids_1: Optional[List[int]] = None) → List[int][source]¶ Create the token type IDs corresponding to the sequences passed. What are token type IDs?
Should be overridden in a subclass if the model has a special way of building those.
- Parameters
token_ids_0 (
List[int]
) – The first tokenized sequence.token_ids_1 (
List[int]
, optional) – The second tokenized sequence.
- Returns
The token type ids.
- Return type
List[int]
-
property
question_token_id
¶ Id of the question token in the vocabulary, used to condition the answer on a question representation.
- Type
Optional[int]
-
save_vocabulary
(save_directory: str, filename_prefix: Optional[str] = None) → Tuple[str][source]¶ Save only the vocabulary of the tokenizer (vocabulary + added tokens).
This method won’t save the configuration and special token mappings of the tokenizer. Use
_save_pretrained()
to save the whole state of the tokenizer.- Parameters
save_directory (
str
) – The directory in which to save the vocabulary.filename_prefix (
str
, optional) – An optional prefix to add to the named of the saved files.
- Returns
Paths to the files saved.
- Return type
Tuple(str)
-
slow_tokenizer_class
¶ alias of
transformers.models.splinter.tokenization_splinter.SplinterTokenizer
SplinterModel¶
-
class
transformers.
SplinterModel
(config)[source]¶ The bare Splinter Model transformer outputting raw hidden-states without any specific head on top. This model is a PyTorch torch.nn.Module sub-class. Use it as a regular PyTorch Module and refer to the PyTorch documentation for all matter related to general usage and behavior.
- Parameters
config (
SplinterConfig
) – Model configuration class with all the parameters of the model. Initializing with a config file does not load the weights associated with the model, only the configuration. Check out thefrom_pretrained()
method to load the model weights.
The model is an encoder (with only self-attention) following the architecture described in Attention is all you need by Ashish Vaswani, Noam Shazeer, Niki Parmar, Jakob Uszkoreit, Llion Jones, Aidan N. Gomez, Lukasz Kaiser and Illia Polosukhin.
-
forward
(input_ids=None, attention_mask=None, token_type_ids=None, position_ids=None, head_mask=None, inputs_embeds=None, encoder_hidden_states=None, encoder_attention_mask=None, past_key_values=None, use_cache=None, output_attentions=None, output_hidden_states=None, return_dict=None)[source]¶ The
SplinterModel
forward method, overrides the__call__()
special method.Note
Although the recipe for forward pass needs to be defined within this function, one should call the
Module
instance afterwards instead of this since the former takes care of running the pre and post processing steps while the latter silently ignores them.- Parameters
input_ids (
torch.LongTensor
of shape(batch_size, sequence_length)
) –Indices of input sequence tokens in the vocabulary.
Indices can be obtained using
transformers.SplinterTokenizer
. Seetransformers.PreTrainedTokenizer.encode()
andtransformers.PreTrainedTokenizer.__call__()
for details.attention_mask (
torch.FloatTensor
of shapebatch_size, sequence_length
, optional) –Mask to avoid performing attention on padding token indices. Mask values selected in
[0, 1]
:1 for tokens that are not masked,
0 for tokens that are masked.
token_type_ids (
torch.LongTensor
of shapebatch_size, sequence_length
, optional) –Segment token indices to indicate first and second portions of the inputs. Indices are selected in
[0, 1]
:0 corresponds to a sentence A token,
1 corresponds to a sentence B token.
position_ids (
torch.LongTensor
of shapebatch_size, sequence_length
, optional) –Indices of positions of each input sequence tokens in the position embeddings. Selected in the range
[0, config.max_position_embeddings - 1]
.head_mask (
torch.FloatTensor
of shape(num_heads,)
or(num_layers, num_heads)
, optional) –Mask to nullify selected heads of the self-attention modules. Mask values selected in
[0, 1]
:1 indicates the head is not masked,
0 indicates the head is masked.
inputs_embeds (
torch.FloatTensor
of shape(batch_size, sequence_length, hidden_size)
, optional) – Optionally, instead of passinginput_ids
you can choose to directly pass an embedded representation. This is useful if you want more control over how to convert input_ids indices into associated vectors than the model’s internal embedding lookup matrix.output_attentions (
bool
, optional) – Whether or not to return the attentions tensors of all attention layers. Seeattentions
under returned tensors for more detail.output_hidden_states (
bool
, optional) – Whether or not to return the hidden states of all layers. Seehidden_states
under returned tensors for more detail.return_dict (
bool
, optional) – Whether or not to return aModelOutput
instead of a plain tuple.encoder_hidden_states (
torch.FloatTensor
of shape(batch_size, sequence_length, hidden_size)
, optional) – Sequence of hidden-states at the output of the last layer of the encoder. Used in the cross-attention if the model is configured as a decoder.encoder_attention_mask (
torch.FloatTensor
of shape(batch_size, sequence_length)
, optional) –Mask to avoid performing attention on the padding token indices of the encoder input. This mask is used in the cross-attention if the model is configured as a decoder. Mask values selected in
[0, 1]
:1 for tokens that are not masked,
0 for tokens that are masked.
past_key_values (
tuple(tuple(torch.FloatTensor))
of lengthconfig.n_layers
with each tuple having 4 tensors of shape(batch_size, num_heads, sequence_length - 1, embed_size_per_head)
) – Contains precomputed key and value hidden states of the attention blocks. Can be used to speed up decoding. Ifpast_key_values
are used, the user can optionally input only the lastdecoder_input_ids
(those that don’t have their past key value states given to this model) of shape(batch_size, 1)
instead of alldecoder_input_ids
of shape(batch_size, sequence_length)
.use_cache (
bool
, optional) – If set toTrue
,past_key_values
key value states are returned and can be used to speed up decoding (seepast_key_values
).
- Returns
A
BaseModelOutputWithPastAndCrossAttentions
or a tuple oftorch.FloatTensor
(ifreturn_dict=False
is passed or whenconfig.return_dict=False
) comprising various elements depending on the configuration (SplinterConfig
) and inputs.last_hidden_state (
torch.FloatTensor
of shape(batch_size, sequence_length, hidden_size)
) – Sequence of hidden-states at the output of the last layer of the model.If
past_key_values
is used only the last hidden-state of the sequences of shape(batch_size, 1, hidden_size)
is output.past_key_values (
tuple(tuple(torch.FloatTensor))
, optional, returned whenuse_cache=True
is passed or whenconfig.use_cache=True
) – Tuple oftuple(torch.FloatTensor)
of lengthconfig.n_layers
, with each tuple having 2 tensors of shape(batch_size, num_heads, sequence_length, embed_size_per_head)
) and optionally ifconfig.is_encoder_decoder=True
2 additional tensors of shape(batch_size, num_heads, encoder_sequence_length, embed_size_per_head)
.Contains pre-computed hidden-states (key and values in the self-attention blocks and optionally if
config.is_encoder_decoder=True
in the cross-attention blocks) that can be used (seepast_key_values
input) to speed up sequential decoding.hidden_states (
tuple(torch.FloatTensor)
, optional, returned whenoutput_hidden_states=True
is passed or whenconfig.output_hidden_states=True
) – Tuple oftorch.FloatTensor
(one for the output of the embeddings + one for the output of each layer) of shape(batch_size, sequence_length, hidden_size)
.Hidden-states of the model at the output of each layer plus the initial embedding outputs.
attentions (
tuple(torch.FloatTensor)
, optional, returned whenoutput_attentions=True
is passed or whenconfig.output_attentions=True
) – Tuple oftorch.FloatTensor
(one for each layer) of shape(batch_size, num_heads, sequence_length, sequence_length)
.Attentions weights after the attention softmax, used to compute the weighted average in the self-attention heads.
cross_attentions (
tuple(torch.FloatTensor)
, optional, returned whenoutput_attentions=True
andconfig.add_cross_attention=True
is passed or whenconfig.output_attentions=True
) – Tuple oftorch.FloatTensor
(one for each layer) of shape(batch_size, num_heads, sequence_length, sequence_length)
.Attentions weights of the decoder’s cross-attention layer, after the attention softmax, used to compute the weighted average in the cross-attention heads.
- Return type
BaseModelOutputWithPastAndCrossAttentions
ortuple(torch.FloatTensor)
Example:
>>> from transformers import SplinterTokenizer, SplinterModel >>> import torch >>> tokenizer = SplinterTokenizer.from_pretrained('tau/splinter-base') >>> model = SplinterModel.from_pretrained('tau/splinter-base') >>> inputs = tokenizer("Hello, my dog is cute", return_tensors="pt") >>> outputs = model(**inputs) >>> last_hidden_states = outputs.last_hidden_state
SplinterForQuestionAnswering¶
-
class
transformers.
SplinterForQuestionAnswering
(config)[source]¶ Splinter Model with a span classification head on top for extractive question-answering tasks like SQuAD (a linear layers on top of the hidden-states output to compute span start logits and span end logits).
This model is a PyTorch torch.nn.Module sub-class. Use it as a regular PyTorch Module and refer to the PyTorch documentation for all matter related to general usage and behavior.
- Parameters
config (
SplinterConfig
) – Model configuration class with all the parameters of the model. Initializing with a config file does not load the weights associated with the model, only the configuration. Check out thefrom_pretrained()
method to load the model weights.
-
forward
(input_ids=None, attention_mask=None, token_type_ids=None, position_ids=None, head_mask=None, inputs_embeds=None, start_positions=None, end_positions=None, output_attentions=None, output_hidden_states=None, return_dict=None, question_positions=None)[source]¶ The
SplinterForQuestionAnswering
forward method, overrides the__call__()
special method.Note
Although the recipe for forward pass needs to be defined within this function, one should call the
Module
instance afterwards instead of this since the former takes care of running the pre and post processing steps while the latter silently ignores them.- Parameters
input_ids (
torch.LongTensor
of shape(batch_size, sequence_length)
) –Indices of input sequence tokens in the vocabulary.
Indices can be obtained using
transformers.SplinterTokenizer
. Seetransformers.PreTrainedTokenizer.encode()
andtransformers.PreTrainedTokenizer.__call__()
for details.attention_mask (
torch.FloatTensor
of shapebatch_size, sequence_length
, optional) –Mask to avoid performing attention on padding token indices. Mask values selected in
[0, 1]
:1 for tokens that are not masked,
0 for tokens that are masked.
token_type_ids (
torch.LongTensor
of shapebatch_size, sequence_length
, optional) –Segment token indices to indicate first and second portions of the inputs. Indices are selected in
[0, 1]
:0 corresponds to a sentence A token,
1 corresponds to a sentence B token.
position_ids (
torch.LongTensor
of shapebatch_size, sequence_length
, optional) –Indices of positions of each input sequence tokens in the position embeddings. Selected in the range
[0, config.max_position_embeddings - 1]
.head_mask (
torch.FloatTensor
of shape(num_heads,)
or(num_layers, num_heads)
, optional) –Mask to nullify selected heads of the self-attention modules. Mask values selected in
[0, 1]
:1 indicates the head is not masked,
0 indicates the head is masked.
inputs_embeds (
torch.FloatTensor
of shape(batch_size, sequence_length, hidden_size)
, optional) – Optionally, instead of passinginput_ids
you can choose to directly pass an embedded representation. This is useful if you want more control over how to convert input_ids indices into associated vectors than the model’s internal embedding lookup matrix.output_attentions (
bool
, optional) – Whether or not to return the attentions tensors of all attention layers. Seeattentions
under returned tensors for more detail.output_hidden_states (
bool
, optional) – Whether or not to return the hidden states of all layers. Seehidden_states
under returned tensors for more detail.return_dict (
bool
, optional) – Whether or not to return aModelOutput
instead of a plain tuple.start_positions (
torch.LongTensor
of shape(batch_size,)
, optional) – Labels for position (index) of the start of the labelled span for computing the token classification loss. Positions are clamped to the length of the sequence (sequence_length
). Position outside of the sequence are not taken into account for computing the loss.end_positions (
torch.LongTensor
of shape(batch_size,)
, optional) – Labels for position (index) of the end of the labelled span for computing the token classification loss. Positions are clamped to the length of the sequence (sequence_length
). Position outside of the sequence are not taken into account for computing the loss.question_positions (
torch.LongTensor
of shape(batch_size, num_questions)
, optional) – The positions of all question tokens. If given, start_logits and end_logits will be of shape(batch_size, num_questions, sequence_length)
. If None, the first question token in each sequence in the batch will be the only one for which start_logits and end_logits are calculated and they will be of shape(batch_size, sequence_length)
.
- Returns
A
QuestionAnsweringModelOutput
or a tuple oftorch.FloatTensor
(ifreturn_dict=False
is passed or whenconfig.return_dict=False
) comprising various elements depending on the configuration (SplinterConfig
) and inputs.loss (
torch.FloatTensor
of shape(1,)
, optional, returned whenlabels
is provided) – Total span extraction loss is the sum of a Cross-Entropy for the start and end positions.start_logits (
torch.FloatTensor
of shape(batch_size, sequence_length)
) – Span-start scores (before SoftMax).end_logits (
torch.FloatTensor
of shape(batch_size, sequence_length)
) – Span-end scores (before SoftMax).hidden_states (
tuple(torch.FloatTensor)
, optional, returned whenoutput_hidden_states=True
is passed or whenconfig.output_hidden_states=True
) – Tuple oftorch.FloatTensor
(one for the output of the embeddings + one for the output of each layer) of shape(batch_size, sequence_length, hidden_size)
.Hidden-states of the model at the output of each layer plus the initial embedding outputs.
attentions (
tuple(torch.FloatTensor)
, optional, returned whenoutput_attentions=True
is passed or whenconfig.output_attentions=True
) – Tuple oftorch.FloatTensor
(one for each layer) of shape(batch_size, num_heads, sequence_length, sequence_length)
.Attentions weights after the attention softmax, used to compute the weighted average in the self-attention heads.
- Return type
QuestionAnsweringModelOutput
ortuple(torch.FloatTensor)
Example:
>>> from transformers import SplinterTokenizer, SplinterForQuestionAnswering >>> import torch >>> tokenizer = SplinterTokenizer.from_pretrained('tau/splinter-base') >>> model = SplinterForQuestionAnswering.from_pretrained('tau/splinter-base') >>> question, text = "Who was Jim Henson?", "Jim Henson was a nice puppet" >>> inputs = tokenizer(question, text, return_tensors='pt') >>> start_positions = torch.tensor([1]) >>> end_positions = torch.tensor([3]) >>> outputs = model(**inputs, start_positions=start_positions, end_positions=end_positions) >>> loss = outputs.loss >>> start_scores = outputs.start_logits >>> end_scores = outputs.end_logits