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reCAPTCHA: Human-Based Character Recognition via Web Security Measures
Abstract
CAPTCHAs (Completely Automated Public Turing test to tell Computers and Humans Apart) are widespread security measures on the World Wide Web that prevent automated programs from abusing online services. They do so by asking humans to perform a task that computers cannot yet perform, such as deciphering distorted characters. Our research explored whether such human effort can be channeled into a useful purpose: helping to digitize old printed material by asking users to decipher scanned words from books that computerized optical character recognition failed to recognize. We showed that this method can transcribe text with a word accuracy exceeding 99%, matching the guarantee of professional human transcribers. Our apparatus is deployed in more than 40,000 Web sites and has transcribed over 440 million words.
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Cited by
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Chandler, J., Mueller, P., & Paolacci, G. (2014) · Behavior Research Methods · doi:10.3758/s13428-013-0365-7 · Cited by 950
AggNet: Deep Learning From Crowds for Mitosis Detection in Breast Cancer Histology Images
Albarqouni, S., Baur, C., Achilles, F., Belagiannis, V., Demirci, S., & Navab, N. (2016) · IEEE Transactions on Medical Imaging · doi:10.1109/tmi.2016.2528120 · Cited by 606
The shape of and solutions to the MTurk quality crisis
Kennedy, R., Clifford, S., Burleigh, T., Waggoner, P. D., Jewell, R., & Winter, N. J. G. (2020) · Political Science Research and Methods · doi:10.1017/psrm.2020.6 · Cited by 506
Truth inference in crowdsourcing: is the problem solved?
Zheng, Y., Li, G., Li, Y., Shan, C., & Cheng, R. (2017) · Proceedings of the VLDB Endowment · doi:10.14778/3055540.3055547 · Cited by 421
Metadata
- Authors
- von Ahn, L., Maurer, B., McMillen, C., Abraham, D., & Blum, M.
- Venue
- Science
- Published
- 2008-09-12
- Volume
- 321
- Issue
- 5895
- Pages
- 1465-1468
- ISSN
- 0036-8075 (ISSN-L)
- 1095-9203
- OpenAlex
- W2022710553
- Cited by
- 1,115
- References
- 0
- FWCI
- 173.03
- Type
- journal article
- Language
- en
- Open access
- closed
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- von Ahn, L., Maurer, B., McMillen, C., Abraham, D., & Blum, M. (2008). reCAPTCHA: Human-Based Character Recognition via Web Security Measures. Science. https://doi.org/10.1126/science.1160379
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
