Incorporating Crowdsourced Annotator Distributions into Ensemble Modeling to Improve Classification Trustworthiness for Ancient Greek Papyri

Performing classification on noisy, crowdsourced image datasets can prove challenging even for the best neural networks. Two issues which complicate the problem on such datasets are class imbalance and ground-truth uncertainty in labeling. The AL-ALL and AL-PUB datasets - consisting of tightly cropp...

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Main Authors: Graham West, Matthew I. Swindall, Ben Keener, Timothy Player, Alex C. Williams, James H. Brusuelas, John F. Wallin
Format: Article
Language:English
Published: Nicolas Turenne 2024-02-01
Series:Journal of Data Mining and Digital Humanities
Subjects:
Online Access:https://jdmdh.episciences.org/10297/pdf
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author Graham West
Matthew I. Swindall
Ben Keener
Timothy Player
Alex C. Williams
James H. Brusuelas
John F. Wallin
author_facet Graham West
Matthew I. Swindall
Ben Keener
Timothy Player
Alex C. Williams
James H. Brusuelas
John F. Wallin
author_sort Graham West
collection DOAJ
description Performing classification on noisy, crowdsourced image datasets can prove challenging even for the best neural networks. Two issues which complicate the problem on such datasets are class imbalance and ground-truth uncertainty in labeling. The AL-ALL and AL-PUB datasets - consisting of tightly cropped, individual characters from images of ancient Greek papyri - are strongly affected by both issues. The application of ensemble modeling to such datasets can help identify images where the ground-truth is questionable and quantify the trustworthiness of those samples. As such, we apply stacked generalization consisting of nearly identical ResNets with different loss functions: one utilizing sparse cross-entropy (CXE) and the other Kullback-Liebler Divergence (KLD). Both networks use labels drawn from a crowd-sourced consensus. This consensus is derived from a Normalized Distribution of Annotations (NDA) based on all annotations for a given character in the dataset. For the second network, the KLD is calculated with respect to the NDA. For our ensemble model, we apply a k-nearest neighbors model to the outputs of the CXE and KLD networks. Individually, the ResNet models have approximately 93% accuracy, while the ensemble model achieves an accuracy of > 95%, increasing the classification trustworthiness. We also perform an analysis of the Shannon entropy of the various models' output distributions to measure classification uncertainty. Our results suggest that entropy is useful for predicting model misclassifications.
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spelling doaj.art-ddda7a46187541e1bd55ce683f39a3dd2024-03-08T15:27:53ZengNicolas TurenneJournal of Data Mining and Digital Humanities2416-59992024-02-012024Digital humanities in...10.46298/jdmdh.1029710297Incorporating Crowdsourced Annotator Distributions into Ensemble Modeling to Improve Classification Trustworthiness for Ancient Greek PapyriGraham West0https://orcid.org/0000-0002-7095-1894Matthew I. Swindall1https://orcid.org/0000-0002-2507-6963Ben Keener2Timothy Player3https://orcid.org/0000-0002-8397-995XAlex C. Williams4James H. Brusuelas5John F. Wallin6https://orcid.org/0000-0001-5678-8325Middle Tennessee State UniversityMiddle Tennessee State UniversityUniversity of Tennessee at KnoxvilleUniversity of Tennessee at KnoxvilleAmazon (United States)University of KentuckyMiddle Tennessee State UniversityPerforming classification on noisy, crowdsourced image datasets can prove challenging even for the best neural networks. Two issues which complicate the problem on such datasets are class imbalance and ground-truth uncertainty in labeling. The AL-ALL and AL-PUB datasets - consisting of tightly cropped, individual characters from images of ancient Greek papyri - are strongly affected by both issues. The application of ensemble modeling to such datasets can help identify images where the ground-truth is questionable and quantify the trustworthiness of those samples. As such, we apply stacked generalization consisting of nearly identical ResNets with different loss functions: one utilizing sparse cross-entropy (CXE) and the other Kullback-Liebler Divergence (KLD). Both networks use labels drawn from a crowd-sourced consensus. This consensus is derived from a Normalized Distribution of Annotations (NDA) based on all annotations for a given character in the dataset. For the second network, the KLD is calculated with respect to the NDA. For our ensemble model, we apply a k-nearest neighbors model to the outputs of the CXE and KLD networks. Individually, the ResNet models have approximately 93% accuracy, while the ensemble model achieves an accuracy of > 95%, increasing the classification trustworthiness. We also perform an analysis of the Shannon entropy of the various models' output distributions to measure classification uncertainty. Our results suggest that entropy is useful for predicting model misclassifications.https://jdmdh.episciences.org/10297/pdfcomputer science - computer vision and pattern recognitioncomputer science - machine learning
spellingShingle Graham West
Matthew I. Swindall
Ben Keener
Timothy Player
Alex C. Williams
James H. Brusuelas
John F. Wallin
Incorporating Crowdsourced Annotator Distributions into Ensemble Modeling to Improve Classification Trustworthiness for Ancient Greek Papyri
Journal of Data Mining and Digital Humanities
computer science - computer vision and pattern recognition
computer science - machine learning
title Incorporating Crowdsourced Annotator Distributions into Ensemble Modeling to Improve Classification Trustworthiness for Ancient Greek Papyri
title_full Incorporating Crowdsourced Annotator Distributions into Ensemble Modeling to Improve Classification Trustworthiness for Ancient Greek Papyri
title_fullStr Incorporating Crowdsourced Annotator Distributions into Ensemble Modeling to Improve Classification Trustworthiness for Ancient Greek Papyri
title_full_unstemmed Incorporating Crowdsourced Annotator Distributions into Ensemble Modeling to Improve Classification Trustworthiness for Ancient Greek Papyri
title_short Incorporating Crowdsourced Annotator Distributions into Ensemble Modeling to Improve Classification Trustworthiness for Ancient Greek Papyri
title_sort incorporating crowdsourced annotator distributions into ensemble modeling to improve classification trustworthiness for ancient greek papyri
topic computer science - computer vision and pattern recognition
computer science - machine learning
url https://jdmdh.episciences.org/10297/pdf
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