spaCy/website/docs/api/entitylinker.md
Paul O'Leary McCann 91acc3ea75
Fix entity linker batching (#9669)
* Partial fix of entity linker batching

* Add import

* Better name

* Add `use_gold_ents` option, docs

* Change to v2, create stub v1, update docs etc.

* Fix error type

Honestly no idea what the right type to use here is.
ConfigValidationError seems wrong. Maybe a NotImplementedError?

* Make mypy happy

* Add hacky fix for init issue

* Add legacy pipeline entity linker

* Fix references to class name

* Add __init__.py for legacy

* Attempted fix for loss issue

* Remove placeholder V1

* formatting

* slightly more interesting train data

* Handle batches with no usable examples

This adds a test for batches that have docs but not entities, and a
check in the component that detects such cases and skips the update step
as thought the batch were empty.

* Remove todo about data verification

Check for empty data was moved further up so this should be OK now - the
case in question shouldn't be possible.

* Fix gradient calculation

The model doesn't know which entities are not in the kb, so it generates
embeddings for the context of all of them.

However, the loss does know which entities aren't in the kb, and it
ignores them, as there's no sensible gradient.

This has the issue that the gradient will not be calculated for some of
the input embeddings, which causes a dimension mismatch in backprop.
That should have caused a clear error, but with numpyops it was causing
nans to happen, which is another problem that should be addressed
separately.

This commit changes the loss to give a zero gradient for entities not in
the kb.

* add failing test for v1 EL legacy architecture

* Add nasty but simple working check for legacy arch

* Clarify why init hack works the way it does

* Clarify use_gold_ents use case

* Fix use gold ents related handling

* Add tests for no gold ents and fix other tests

* Use aligned ents function (not working)

This doesn't actually work because the "aligned" ents are gold-only. But
if I have a different function that returns the intersection, *then*
this will work as desired.

* Use proper matching ent check

This changes the process when gold ents are not used so that the
intersection of ents in the pred and gold is used.

* Move get_matching_ents to Example

* Use model attribute to check for legacy arch

* Rename flag

* bump spacy-legacy to lower 3.0.9

Co-authored-by: svlandeg <svlandeg@github.com>
2022-03-04 09:17:36 +01:00

22 KiB

title tag source new teaser api_base_class api_string_name api_trainable
EntityLinker class spacy/pipeline/entity_linker.py 2.2 Pipeline component for named entity linking and disambiguation /api/pipe entity_linker true

An EntityLinker component disambiguates textual mentions (tagged as named entities) to unique identifiers, grounding the named entities into the "real world". It requires a KnowledgeBase, as well as a function to generate plausible candidates from that KnowledgeBase given a certain textual mention, and a machine learning model to pick the right candidate, given the local context of the mention.

Assigned Attributes

Predictions, in the form of knowledge base IDs, will be assigned to Token.ent_kb_id_.

Location Value
Token.ent_kb_id Knowledge base ID (hash). int
Token.ent_kb_id_ Knowledge base ID. str

Config and implementation

The default config is defined by the pipeline component factory and describes how the component should be configured. You can override its settings via the config argument on nlp.add_pipe or in your config.cfg for training. See the model architectures documentation for details on the architectures and their arguments and hyperparameters.

Example

from spacy.pipeline.entity_linker import DEFAULT_NEL_MODEL
config = {
   "labels_discard": [],
   "n_sents": 0,
   "incl_prior": True,
   "incl_context": True,
   "model": DEFAULT_NEL_MODEL,
   "entity_vector_length": 64,
   "get_candidates": {'@misc': 'spacy.CandidateGenerator.v1'},
}
nlp.add_pipe("entity_linker", config=config)
Setting Description
labels_discard NER labels that will automatically get a "NIL" prediction. Defaults to []. Iterable[str]
n_sents The number of neighbouring sentences to take into account. Defaults to 0. int
incl_prior Whether or not to include prior probabilities from the KB in the model. Defaults to True. bool
incl_context Whether or not to include the local context in the model. Defaults to True. bool
model The Model powering the pipeline component. Defaults to EntityLinker. Model
entity_vector_length Size of encoding vectors in the KB. Defaults to 64. int
use_gold_ents Whether to copy entities from the gold docs or not. Defaults to True. If False, entities must be set in the training data or by an annotating component in the pipeline. int
get_candidates Function that generates plausible candidates for a given Span object. Defaults to CandidateGenerator, a function looking up exact, case-dependent aliases in the KB. CallableKnowledgeBase, Span], Iterable[Candidate
overwrite 3.2 Whether existing annotation is overwritten. Defaults to True. bool
scorer 3.2 The scoring method. Defaults to Scorer.score_links. Optional[Callable]
%%GITHUB_SPACY/spacy/pipeline/entity_linker.py

EntityLinker.__init__

Example

# Construction via add_pipe with default model
entity_linker = nlp.add_pipe("entity_linker")

# Construction via add_pipe with custom model
config = {"model": {"@architectures": "my_el.v1"}}
entity_linker = nlp.add_pipe("entity_linker", config=config)

# Construction from class
from spacy.pipeline import EntityLinker
entity_linker = EntityLinker(nlp.vocab, model)

Create a new pipeline instance. In your application, you would normally use a shortcut for this and instantiate the component using its string name and nlp.add_pipe.

Upon construction of the entity linker component, an empty knowledge base is constructed with the provided entity_vector_length. If you want to use a custom knowledge base, you should either call set_kb or provide a kb_loader in the initialize call.

Name Description
vocab The shared vocabulary. Vocab
model The Model powering the pipeline component. Model
name String name of the component instance. Used to add entries to the losses during training. str
keyword-only
entity_vector_length Size of encoding vectors in the KB. int
get_candidates Function that generates plausible candidates for a given Span object. CallableKnowledgeBase, Span], Iterable[Candidate
labels_discard NER labels that will automatically get a "NIL" prediction. Iterable[str]
n_sents The number of neighbouring sentences to take into account. int
incl_prior Whether or not to include prior probabilities from the KB in the model. bool
incl_context Whether or not to include the local context in the model. bool
overwrite 3.2 Whether existing annotation is overwritten. Defaults to True. bool
scorer 3.2 The scoring method. Defaults to Scorer.score_links. Optional[Callable]

EntityLinker.__call__

Apply the pipe to one document. The document is modified in place and returned. This usually happens under the hood when the nlp object is called on a text and all pipeline components are applied to the Doc in order. Both __call__ and pipe delegate to the predict and set_annotations methods.

Example

doc = nlp("This is a sentence.")
entity_linker = nlp.add_pipe("entity_linker")
# This usually happens under the hood
processed = entity_linker(doc)
Name Description
doc The document to process. Doc
RETURNS The processed document. Doc

EntityLinker.pipe

Apply the pipe to a stream of documents. This usually happens under the hood when the nlp object is called on a text and all pipeline components are applied to the Doc in order. Both __call__ and pipe delegate to the predict and set_annotations methods.

Example

entity_linker = nlp.add_pipe("entity_linker")
for doc in entity_linker.pipe(docs, batch_size=50):
    pass
Name Description
stream A stream of documents. Iterable[Doc]
keyword-only
batch_size The number of documents to buffer. Defaults to 128. int
YIELDS The processed documents in order. Doc

EntityLinker.set_kb

The kb_loader should be a function that takes a Vocab instance and creates the KnowledgeBase, ensuring that the strings of the knowledge base are synced with the current vocab.

Example

def create_kb(vocab):
    kb = KnowledgeBase(vocab, entity_vector_length=128)
    kb.add_entity(...)
    kb.add_alias(...)
    return kb
entity_linker = nlp.add_pipe("entity_linker")
entity_linker.set_kb(create_kb)
Name Description
kb_loader Function that creates a KnowledgeBase from a Vocab instance. Callable[[Vocab], KnowledgeBase]

EntityLinker.initialize

Initialize the component for training. get_examples should be a function that returns an iterable of Example objects. The data examples are used to initialize the model of the component and can either be the full training data or a representative sample. Initialization includes validating the network, inferring missing shapes and setting up the label scheme based on the data. This method is typically called by Language.initialize.

Optionally, a kb_loader argument may be specified to change the internal knowledge base. This argument should be a function that takes a Vocab instance and creates the KnowledgeBase, ensuring that the strings of the knowledge base are synced with the current vocab.

This method was previously called begin_training.

Example

entity_linker = nlp.add_pipe("entity_linker")
entity_linker.initialize(lambda: [], nlp=nlp, kb_loader=my_kb)
Name Description
get_examples Function that returns gold-standard annotations in the form of Example objects. Callable], Iterable[Example
keyword-only
nlp The current nlp object. Defaults to None. Optional[Language]
kb_loader Function that creates a KnowledgeBase from a Vocab instance. Callable[[Vocab], KnowledgeBase]

EntityLinker.predict

Apply the component's model to a batch of Doc objects, without modifying them. Returns the KB IDs for each entity in each doc, including NIL if there is no prediction.

Example

entity_linker = nlp.add_pipe("entity_linker")
kb_ids = entity_linker.predict([doc1, doc2])
Name Description
docs The documents to predict. Iterable[Doc]
RETURNS The predicted KB identifiers for the entities in the docs. List[str]

EntityLinker.set_annotations

Modify a batch of documents, using pre-computed entity IDs for a list of named entities.

Example

entity_linker = nlp.add_pipe("entity_linker")
kb_ids = entity_linker.predict([doc1, doc2])
entity_linker.set_annotations([doc1, doc2], kb_ids)
Name Description
docs The documents to modify. Iterable[Doc]
kb_ids The knowledge base identifiers for the entities in the docs, predicted by EntityLinker.predict. List[str]

EntityLinker.update

Learn from a batch of Example objects, updating both the pipe's entity linking model and context encoder. Delegates to predict.

Example

entity_linker = nlp.add_pipe("entity_linker")
optimizer = nlp.initialize()
losses = entity_linker.update(examples, sgd=optimizer)
Name Description
examples A batch of Example objects to learn from. Iterable[Example]
keyword-only
drop The dropout rate. float
sgd An optimizer. Will be created via create_optimizer if not set. Optional[Optimizer]
losses Optional record of the loss during training. Updated using the component name as the key. Optional[Dict[str, float]]
RETURNS The updated losses dictionary. Dict[str, float]

EntityLinker.create_optimizer

Create an optimizer for the pipeline component.

Example

entity_linker = nlp.add_pipe("entity_linker")
optimizer = entity_linker.create_optimizer()
Name Description
RETURNS The optimizer. Optimizer

EntityLinker.use_params

Modify the pipe's model, to use the given parameter values. At the end of the context, the original parameters are restored.

Example

entity_linker = nlp.add_pipe("entity_linker")
with entity_linker.use_params(optimizer.averages):
    entity_linker.to_disk("/best_model")
Name Description
params The parameter values to use in the model. dict

EntityLinker.to_disk

Serialize the pipe to disk.

Example

entity_linker = nlp.add_pipe("entity_linker")
entity_linker.to_disk("/path/to/entity_linker")
Name Description
path A path to a directory, which will be created if it doesn't exist. Paths may be either strings or Path-like objects. Union[str, Path]
keyword-only
exclude String names of serialization fields to exclude. Iterable[str]

EntityLinker.from_disk

Load the pipe from disk. Modifies the object in place and returns it.

Example

entity_linker = nlp.add_pipe("entity_linker")
entity_linker.from_disk("/path/to/entity_linker")
Name Description
path A path to a directory. Paths may be either strings or Path-like objects. Union[str, Path]
keyword-only
exclude String names of serialization fields to exclude. Iterable[str]
RETURNS The modified EntityLinker object. EntityLinker

EntityLinker.to_bytes

Example

entity_linker = nlp.add_pipe("entity_linker")
entity_linker_bytes = entity_linker.to_bytes()

Serialize the pipe to a bytestring, including the KnowledgeBase.

Name Description
keyword-only
exclude String names of serialization fields to exclude. Iterable[str]
RETURNS The serialized form of the EntityLinker object. bytes

EntityLinker.from_bytes

Load the pipe from a bytestring. Modifies the object in place and returns it.

Example

entity_linker_bytes = entity_linker.to_bytes()
entity_linker = nlp.add_pipe("entity_linker")
entity_linker.from_bytes(entity_linker_bytes)
Name Description
bytes_data The data to load from. bytes
keyword-only
exclude String names of serialization fields to exclude. Iterable[str]
RETURNS The EntityLinker object. EntityLinker

Serialization fields

During serialization, spaCy will export several data fields used to restore different aspects of the object. If needed, you can exclude them from serialization by passing in the string names via the exclude argument.

Example

data = entity_linker.to_disk("/path", exclude=["vocab"])
Name Description
vocab The shared Vocab.
cfg The config file. You usually don't want to exclude this.
model The binary model data. You usually don't want to exclude this.
kb The knowledge base. You usually don't want to exclude this.