sparknlp.annotator.embeddings.albert_embeddings#

Classes#

class AlbertEmbeddings(classname='com.johnsnowlabs.nlp.embeddings.AlbertEmbeddings', java_model=None)[source]#

ALBERT: A Lite Bert For Self-Supervised Learning Of Language Representations - Google Research, Toyota Technological Institute at Chicago

These word embeddings represent the outputs generated by the Albert model. All official Albert releases by google in TF-HUB are supported with this Albert Wrapper:

Ported TF-Hub Models:

Model Name	TF-Hub Model	Model Properties
"albert_base_uncased"	albert_base	768-embed-dim, 12-layer, 12-heads, 12M parameters
"albert_large_uncased"	albert_large	1024-embed-dim, 24-layer, 16-heads, 18M parameters
"albert_xlarge_uncased"	albert_xlarge	2048-embed-dim, 24-layer, 32-heads, 60M parameters
"albert_xxlarge_uncased"	albert_xxlarge	4096-embed-dim, 12-layer, 64-heads, 235M parameters

This model requires input tokenization with SentencePiece model, which is provided by Spark-NLP (See tokenizers package).

Pretrained models can be loaded with pretrained() of the companion object:

>>> embeddings = AlbertEmbeddings.pretrained() \
...    .setInputCols(["sentence", "token"]) \
...    .setOutputCol("embeddings")

The default model is "albert_base_uncased", if no name is provided.

For extended examples of usage, see the Examples. To see which models are compatible and how to import them see Import Transformers into Spark NLP 🚀.

Input Annotation types	Output Annotation type
DOCUMENT, TOKEN	WORD_EMBEDDINGS

Parameters:

batchSize

Size of every batch, by default 8

dimension

Number of embedding dimensions, by default 768

caseSensitive

Whether to ignore case in tokens for embeddings matching, by default False

configProtoBytes

ConfigProto from tensorflow, serialized into byte array.

maxSentenceLength

Max sentence length to process, by default 128

See also

AlbertForTokenClassification

for AlbertEmbeddings with a token classification layer on top

Notes

ALBERT uses repeating layers which results in a small memory footprint, however the computational cost remains similar to a BERT-like architecture with the same number of hidden layers as it has to iterate through the same number of (repeating) layers.

References

ALBERT: A LITE BERT FOR SELF-SUPERVISED LEARNING OF LANGUAGE REPRESENTATIONS

google-research/ALBERT

https://tfhub.dev/s?q=albert

Paper abstract:

Increasing model size when pretraining natural language representations often results in improved performance on downstream tasks. However, at some point further model increases become harder due to GPU/TPU memory limitations and longer training times. To address these problems, we present two parameter reduction techniques to lower memory consumption and increase the training speed of BERT (Devlin et al., 2019). Comprehensive empirical evidence shows that our proposed methods lead to models that scale much better compared to the original BERT. We also use a self-supervised loss that focuses on modeling inter-sentence coherence, and show it consistently helps downstream tasks with multi-sentence inputs. As a result, our best model establishes new state-of-the-art results on the GLUE, RACE, and SQuAD benchmarks while having fewer parameters compared to BERT-large.

Examples

>>> import sparknlp
>>> from sparknlp.base import *
>>> from sparknlp.annotator import *
>>> from pyspark.ml import Pipeline
>>> documentAssembler = DocumentAssembler() \
...     .setInputCol("text") \
...     .setOutputCol("document")
>>> tokenizer = Tokenizer() \
...     .setInputCols(["document"]) \
>>> embeddings = AlbertEmbeddings.pretrained() \
...     .setInputCols(["token", "document"]) \
...     .setOutputCol("embeddings")
>>> embeddingsFinisher = EmbeddingsFinisher() \
...     .setInputCols(["embeddings"]) \
...     .setOutputCols("finished_embeddings") \
...     .setOutputAsVector(True) \
...     .setCleanAnnotations(False)
>>> pipeline = Pipeline().setStages([
...     documentAssembler,
...     tokenizer,
...     embeddings,
...     embeddingsFinisher
... ])
>>> data = spark.createDataFrame([["This is a sentence."]]).toDF("text")
>>> result = pipeline.fit(data).transform(data)
>>> result.selectExpr("explode(finished_embeddings) as result").show(5, 80)
+--------------------------------------------------------------------------------+
|                                                                          result|
+--------------------------------------------------------------------------------+
|[1.1342473030090332,-1.3855540752410889,0.9818322062492371,-0.784737348556518...|
|[0.847029983997345,-1.047153353691101,-0.1520637571811676,-0.6245765686035156...|
|[-0.009860038757324219,-0.13450059294700623,2.707749128341675,1.2916892766952...|
|[-0.04192575812339783,-0.5764210224151611,-0.3196685314178467,-0.527840495109...|
|[0.15583214163780212,-0.1614152491092682,-0.28423872590065,-0.135491415858268...|
+--------------------------------------------------------------------------------+

setConfigProtoBytes(b)[source]#

Sets configProto from tensorflow, serialized into byte array.

Parameters:

bList[int]

ConfigProto from tensorflow, serialized into byte array

static loadSavedModel(folder, spark_session)[source]#

Loads a locally saved model.

Parameters:

folderstr

Folder of the saved model

spark_sessionpyspark.sql.SparkSession

The current SparkSession

Returns:

AlbertEmbeddings

The restored model

static pretrained(name='albert_base_uncased', lang='en', remote_loc=None)[source]#

Downloads and loads a pretrained model.

Parameters:

namestr, optional

Name of the pretrained model, by default “albert_base_uncased”

langstr, optional

Language of the pretrained model, by default “en”

remote_locstr, optional

Optional remote address of the resource, by default None. Will use Spark NLPs repositories otherwise.

Returns:

AlbertEmbeddings

The restored model