The DOI matches its Crossref record.
Telling humans and computers apart automatically
Abstract
How lazy cryptographers do AI.
Overview
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Citations
Cited by
Designing human friendly human interaction proofs (HIPs)
Chellapilla, K., Larson, K., Simard, P., & Czerwinski, M. (2005) · Proceedings of the SIGCHI Conference on Human Factors in Computing Systems · doi:10.1145/1054972.1055070 · Cited by 261
Sybillimit: a near-optimal social network defense against sybil attacks
Yu, H., Gibbons, P. B., Kaminsky, M., & Xiao, F. (2010) · IEEE/ACM Transactions on Networking · doi:10.1109/tnet.2009.2034047 · Cited by 246
Working Together Apart: Collaboration over the Internet
Olson, J. S., & Olson, G. M. (2014) · Synthesis Lectures on Human-Centered Informatics · doi:10.2200/s00542ed1v01y201310hci020 · Cited by 95
Accessible privacy and security: a universally usable human-interaction proof tool
Sauer, G., Holman, J., Lazar, J., Hochheiser, H., & Feng, J. (2010) · Universal Access in the Information Society · doi:10.1007/s10209-009-0171-2 · Cited by 54
Patient-identified events implicated in the development of body dysmorphic disorder
Weingarden, H., Curley, E. E., Renshaw, K. D., & Wilhelm, S. (2017) · Body Image · doi:10.1016/j.bodyim.2017.02.003 · Cited by 48
Metadata
- Authors
- von Ahn, L., Blum, M., & Langford, J.
- Venue
- Communications of the ACM
- Published
- 2004-02
- Volume
- 47
- Issue
- 2
- Pages
- 56-60
- ISSN
- 0001-0782 (ISSN-L)
- 1557-7317
- OpenAlex
- W2072410439
- Cited by
- 895
- References
- 0
- FWCI
- 88.23
- Type
- journal article
- Language
- en
- Open access
- closed
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
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How to cite
Cite CoChat for the checks on this page, and the paper for its own findings.
- This page
- CoChat. (2026). Citation check: Telling humans and computers apart automatically. https://app.cochat.ai/papers/10.1145/966389.966390
- The paper
- von Ahn, L., Blum, M., & Langford, J. (2004). Telling humans and computers apart automatically. Communications of the ACM. https://doi.org/10.1145/966389.966390
Data sources
Bibliographic data: Semantic Scholar, OpenAlex, Crossref.
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.