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Crowdsourcing Image Analysis for Plant Phenomics to Generate Ground Truth Data for Machine Learning
  • Zachary D. Siegel, Iowa State University
  • Naihui Zhou, Iowa State University
  • Scott Zarecor, Iowa State University
  • Nigel Lee, Iowa State University
  • Darwin A. Campbell, Iowa State University
  • Carson M. Andorf, United States Department of Agriculture
  • Dan Nettleton, Iowa State University
  • Carolyn J. Lawrence-Dill, Iowa State University
  • Baskar Ganapathysubramanian, Iowa State University
  • Iddo Friedberg, Iowa State University
  • Jonathan W. Kelly, Iowa State University
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The accuracy of machine learning tasks is critically dependent on high quality ground truth data. Therefore, in many cases, producing good ground truth data typically involves trained professionals; however, this can be costly in time, effort, and money. Here we explore the use of crowdsourcing to generate a large number of training data points of good quality. We explore an image analysis task involving the segmentation of corn tassels from images taken in a field setting. We explore the accuracy, speed and other quality metrics when this task is performed by students for academic credit, Amazon MTurk workers, and Master Amazon MTurk workers. We conclude that the Amazon MTurk and Master Mturk workers perform significantly better than the for-credit students, with no significant difference between the two MTurk worker types. The quality of the segmentation produced by Amazon MTurk workers rivals that of an expert worker. We provide best practices to assess the quality of ground truth data, and to compare data quality produced by different sources. We conclude that properly managed crowdsourcing can be used to establish large volumes of viable ground truth data at a low cost and high quality, especially in the context of high throughput plant phenotyping. We also provide several metrics for assessing the quality of the generated datasets.


This is a manuscript of the article Siegel, Zachary D., Naihui Zhou, Scott Zarecor, Nigel Lee, Darwin A. Campbell, Carson M. Andorf, Dan Nettleton et al. "Crowdsourcing Image Analysis for Plant Phenomics to Generate Ground Truth Data for Machine Learning." bioRxiv (2018): 265918. Posted with permission.

Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted.
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Zachary D. Siegel, Naihui Zhou, Scott Zarecor, Nigel Lee, et al.. "Crowdsourcing Image Analysis for Plant Phenomics to Generate Ground Truth Data for Machine Learning" bioRxiv (2018)
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