Angrosh Mandya

Also published as: Mandya Angrosh


Learning to Borrow– Relation Representation for Without-Mention Entity-Pairs for Knowledge Graph Completion
Huda Hakami | Mona Hakami | Angrosh Mandya | Danushka Bollegala
Proceedings of the 2022 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies

Prior work on integrating text corpora with knowledge graphs (KGs) to improve Knowledge Graph Embedding (KGE) have obtained good performance for entities that co-occur in sentences in text corpora. Such sentences (textual mentions of entity-pairs) are represented as Lexicalised Dependency Paths (LDPs) between two entities. However, it is not possible to represent relations between entities that do not co-occur in a single sentence using LDPs. In this paper, we propose and evaluate several methods to address this problem, where we borrow LDPs from the entity pairs that co-occur in sentences in the corpus (i.e. with mentions entity pairs) to represent entity pairs that do not co-occur in any sentence in the corpus (i.e. without mention entity pairs). We propose a supervised borrowing method, SuperBorrow, that learns to score the suitability of an LDP to represent a without-mentions entity pair using pre-trained entity embeddings and contextualised LDP representations. Experimental results show that SuperBorrow improves the link prediction performance of multiple widely-used prior KGE methods such as TransE, DistMult, ComplEx and RotatE.


Graph Convolution over Multiple Dependency Sub-graphs for Relation Extraction
Angrosh Mandya | Danushka Bollegala | Frans Coenen
Proceedings of the 28th International Conference on Computational Linguistics

We propose a contextualised graph convolution network over multiple dependency-based sub-graphs for relation extraction. A novel method to construct multiple sub-graphs using words in shortest dependency path and words linked to entities in the dependency parse is proposed. Graph convolution operation is performed over the resulting multiple sub-graphs to obtain more informative features useful for relation extraction. Our experimental results show that the proposed method achieves superior performance over the existing GCN-based models achieving state-of-the-art performance on cross-sentence n-ary relation extraction dataset and SemEval 2010 Task 8 sentence-level relation extraction dataset. Our model also achieves a comparable performance to the SoTA on the TACRED dataset.

Do not let the history haunt you: Mitigating Compounding Errors in Conversational Question Answering
Angrosh Mandya | James O’ Neill | Danushka Bollegala | Frans Coenen
Proceedings of the Twelfth Language Resources and Evaluation Conference

The Conversational Question Answering (CoQA) task involves answering a sequence of inter-related conversational questions about a contextual paragraph. Although existing approaches employ human-written ground-truth answers for answering conversational questions at test time, in a realistic scenario, the CoQA model will not have any access to ground-truth answers for the previous questions, compelling the model to rely upon its own previously predicted answers for answering the subsequent questions. In this paper, we find that compounding errors occur when using previously predicted answers at test time, significantly lowering the performance of CoQA systems. To solve this problem, we propose a sampling strategy that dynamically selects between target answers and model predictions during training, thereby closely simulating the situation at test time. Further, we analyse the severity of this phenomena as a function of the question type, conversation length and domain type.


A Dataset for Inter-Sentence Relation Extraction using Distant Supervision
Angrosh Mandya | Danushka Bollegala | Frans Coenen | Katie Atkinson
Proceedings of the Eleventh International Conference on Language Resources and Evaluation (LREC 2018)


Scrutable Feature Sets for Stance Classification
Angrosh Mandya | Advaith Siddharthan | Adam Wyner
Proceedings of the Third Workshop on Argument Mining (ArgMining2016)


Text simplification using synchronous dependency grammars: Generalising automatically harvested rules
Mandya Angrosh | Advaith Siddharthan
Proceedings of the 8th International Natural Language Generation Conference (INLG)

Lexico-syntactic text simplification and compression with typed dependencies
Mandya Angrosh | Tadashi Nomoto | Advaith Siddharthan
Proceedings of COLING 2014, the 25th International Conference on Computational Linguistics: Technical Papers

Hybrid text simplification using synchronous dependency grammars with hand-written and automatically harvested rules
Advaith Siddharthan | Angrosh Mandya
Proceedings of the 14th Conference of the European Chapter of the Association for Computational Linguistics