First draft of model card
Browse files
README.md
ADDED
@@ -0,0 +1,105 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
1 |
+
---
|
2 |
+
language: en
|
3 |
+
tags:
|
4 |
+
- tapas
|
5 |
+
- question-answering
|
6 |
+
license: apache-2.0
|
7 |
+
datasets:
|
8 |
+
- msr_sqa
|
9 |
+
---
|
10 |
+
|
11 |
+
# TAPAS mini model fine-tuned on Sequential Question Answering (SQA)
|
12 |
+
|
13 |
+
This model has 2 versions which can be used. The default version corresponds to the `tapas_sqa_inter_masklm_mini_reset` checkpoint of the [original Github repository](https://github.com/google-research/tapas).
|
14 |
+
This model was pre-trained on MLM and an additional step which the authors call intermediate pre-training, and then fine-tuned on [SQA](https://www.microsoft.com/en-us/download/details.aspx?id=54253). It uses relative position embeddings (i.e. resetting the position index at every cell of the table).
|
15 |
+
|
16 |
+
The other (non-default) version which can be used is:
|
17 |
+
- `no_reset`, which corresponds to `tapas_sqa_inter_masklm_mini` (intermediate pre-training, absolute position embeddings).
|
18 |
+
|
19 |
+
Disclaimer: The team releasing TAPAS did not write a model card for this model so this model card has been written by
|
20 |
+
the Hugging Face team and contributors.
|
21 |
+
|
22 |
+
## Model description
|
23 |
+
|
24 |
+
TAPAS is a BERT-like transformers model pretrained on a large corpus of English data from Wikipedia in a self-supervised fashion.
|
25 |
+
This means it was pretrained on the raw tables and associated texts only, with no humans labelling them in any way (which is why it
|
26 |
+
can use lots of publicly available data) with an automatic process to generate inputs and labels from those texts. More precisely, it
|
27 |
+
was pretrained with two objectives:
|
28 |
+
|
29 |
+
- Masked language modeling (MLM): taking a (flattened) table and associated context, the model randomly masks 15% of the words in
|
30 |
+
the input, then runs the entire (partially masked) sequence through the model. The model then has to predict the masked words.
|
31 |
+
This is different from traditional recurrent neural networks (RNNs) that usually see the words one after the other,
|
32 |
+
or from autoregressive models like GPT which internally mask the future tokens. It allows the model to learn a bidirectional
|
33 |
+
representation of a table and associated text.
|
34 |
+
- Intermediate pre-training: to encourage numerical reasoning on tables, the authors additionally pre-trained the model by creating
|
35 |
+
a balanced dataset of millions of syntactically created training examples. Here, the model must predict (classify) whether a sentence
|
36 |
+
is supported or refuted by the contents of a table. The training examples are created based on synthetic as well as counterfactual statements.
|
37 |
+
|
38 |
+
This way, the model learns an inner representation of the English language used in tables and associated texts, which can then be used
|
39 |
+
to extract features useful for downstream tasks such as answering questions about a table, or determining whether a sentence is entailed
|
40 |
+
or refuted by the contents of a table. Fine-tuning is done by adding a cell selection head on top of the pre-trained model, and then jointly
|
41 |
+
train this randomly initialized classification head with the base model on SQA.
|
42 |
+
|
43 |
+
|
44 |
+
## Intended uses & limitations
|
45 |
+
|
46 |
+
You can use this model for answering questions related to a table in a conversational set-up.
|
47 |
+
|
48 |
+
For code examples, we refer to the documentation of TAPAS on the HuggingFace website.
|
49 |
+
|
50 |
+
|
51 |
+
## Training procedure
|
52 |
+
|
53 |
+
### Preprocessing
|
54 |
+
|
55 |
+
The texts are lowercased and tokenized using WordPiece and a vocabulary size of 30,000. The inputs of the model are
|
56 |
+
then of the form:
|
57 |
+
|
58 |
+
```
|
59 |
+
[CLS] Question [SEP] Flattened table [SEP]
|
60 |
+
```
|
61 |
+
|
62 |
+
### Fine-tuning
|
63 |
+
|
64 |
+
The model was fine-tuned on 32 Cloud TPU v3 cores for 200,000 steps with maximum sequence length 512 and batch size of 128.
|
65 |
+
In this setup, fine-tuning takes around 20 hours. The optimizer used is Adam with a learning rate of 1.25e-5, and a warmup ratio
|
66 |
+
of 0.2. An inductive bias is added such that the model only selects cells of the same column. This is reflected by the
|
67 |
+
`select_one_column` parameter of `TapasConfig`. See also table 12 of the [original paper](https://arxiv.org/abs/2004.02349).
|
68 |
+
|
69 |
+
|
70 |
+
### BibTeX entry and citation info
|
71 |
+
|
72 |
+
```bibtex
|
73 |
+
@misc{herzig2020tapas,
|
74 |
+
title={TAPAS: Weakly Supervised Table Parsing via Pre-training},
|
75 |
+
author={Jonathan Herzig and Paweł Krzysztof Nowak and Thomas Müller and Francesco Piccinno and Julian Martin Eisenschlos},
|
76 |
+
year={2020},
|
77 |
+
eprint={2004.02349},
|
78 |
+
archivePrefix={arXiv},
|
79 |
+
primaryClass={cs.IR}
|
80 |
+
}
|
81 |
+
```
|
82 |
+
|
83 |
+
```bibtex
|
84 |
+
@misc{eisenschlos2020understanding,
|
85 |
+
title={Understanding tables with intermediate pre-training},
|
86 |
+
author={Julian Martin Eisenschlos and Syrine Krichene and Thomas Müller},
|
87 |
+
year={2020},
|
88 |
+
eprint={2010.00571},
|
89 |
+
archivePrefix={arXiv},
|
90 |
+
primaryClass={cs.CL}
|
91 |
+
}
|
92 |
+
```
|
93 |
+
|
94 |
+
```bibtex
|
95 |
+
@InProceedings{iyyer2017search-based,
|
96 |
+
author = {Iyyer, Mohit and Yih, Scott Wen-tau and Chang, Ming-Wei},
|
97 |
+
title = {Search-based Neural Structured Learning for Sequential Question Answering},
|
98 |
+
booktitle = {Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics},
|
99 |
+
year = {2017},
|
100 |
+
month = {July},
|
101 |
+
abstract = {Recent work in semantic parsing for question answering has focused on long and complicated questions, many of which would seem unnatural if asked in a normal conversation between two humans. In an effort to explore a conversational QA setting, we present a more realistic task: answering sequences of simple but inter-related questions. We collect a dataset of 6,066 question sequences that inquire about semi-structured tables from Wikipedia, with 17,553 question-answer pairs in total. To solve this sequential question answering task, we propose a novel dynamic neural semantic parsing framework trained using a weakly supervised reward-guided search. Our model effectively leverages the sequential context to outperform state-of-the-art QA systems that are designed to answer highly complex questions.},
|
102 |
+
publisher = {Association for Computational Linguistics},
|
103 |
+
url = {https://www.microsoft.com/en-us/research/publication/search-based-neural-structured-learning-sequential-question-answering/},
|
104 |
+
}
|
105 |
+
```
|