VSNR: A Wavelet-Based Visual Signal-to-Noise Ratio for Natural Images
Abstract
This paper presents an efficient metric for quantifying the visual fidelity of natural images based on near-threshold and suprathreshold properties of human vision. The proposed metric, the visual signal-to-noise ratio (VSNR), operates via a two-stage approach. In the first stage, contrast thresholds for detection of distortions in the presence of natural images are computed via wavelet-based models of visual masking and visual summation in order to determine whether the distortions in the distorted image are visible. If the distortions are below the threshold of detection, the distorted image is deemed to be of perfect visual fidelity (VSNR = infinity) and no further analysis is required. If the distortions are suprathreshold, a second stage is applied which operates based on the low-level visual property of perceived contrast, and the mid-level visual property of global precedence. These two properties are modeled as Euclidean distances in distortion-contrast space of a multiscale wavelet decomposition, and VSNR is computed based on a simple linear sum of these distances. The proposed VSNR metric is generally competitive with current metrics of visual fidelity; it is efficient both in terms of its low computational complexity and in terms of its low memory requirements; and it operates based on physical luminances and visual angle (rather than on digital pixel values and pixel-based dimensions) to accommodate different viewing conditions.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
SSIM, VIF, VSNR and JND are successful full reference algorithms that have been shown to perform well in predicting the quality scores of human subjects.
“The structural similarity index (SSIM) [2], visual information fidelity (VIF) [3], visual signal to noise ratio (VSNR) [4] and just noticeable difference (JND) metrix [5], are examples of successful full reference algorithms which have been shown to perform well in predicting the quality scores of human subjects.”
From RRED Indices: Reduced Reference Entropic Differencing for Image Quality Assessment (2012) · cites this paper as [4]
Cites
Image quality assessment: from error visibility to structural similarity
Wang, Z., Bovik, A. C., Sheikh, H. R., & Simoncelli, E. P. (2004) · IEEE Transactions on Image Processing · doi:10.1109/tip.2003.819861 · Cited by 57,892 · see citing works
A Simplex Method for Function Minimization
Nelder, J. A., & Mead, R. (1965) · The Computer Journal · doi:10.1093/comjnl/7.4.308 · Cited by 28,905 · see citing works
Multiscale structural similarity for image quality assessment
Wang, Z., Simoncelli, E. P., & Bovik, A. C. (2004) · The Thrity-Seventh Asilomar Conference on Signals, Systems & Computers, 2003 · doi:10.1109/acssc.2003.1292216 · Cited by 6,253 · see citing works
A universal image quality index
Wang, Z., & Bovik, A. C. (2002) · IEEE Signal Processing Letters · doi:10.1109/97.995823 · Cited by 5,757 · see citing works
Efficient tests for normality, homoscedasticity and serial independence of regression residuals.
Jarque, C. M., & Bera, A. K. (1980) · Economics Letters · doi:10.1016/0165-1765(80)90024-5 · Cited by 4,338 · see citing works
Image information and visual quality
Sheikh, H. R., & Bovik, A. C. (2006) · IEEE Transactions on Image Processing · doi:10.1109/tip.2005.859378 · Cited by 4,104 · see citing works
Forest before trees: The precedence of global features in visual perception
Navon, D. (1977) · Cognitive Psychology · doi:10.1016/0010-0285(77)90012-3 · Cited by 4,005 · see citing works
A Statistical Evaluation of Recent Full Reference Image Quality Assessment Algorithms
Sheikh, H. R., Sabir, M. F., & Bovik, A. C. (2006) · IEEE Transactions on Image Processing · doi:10.1109/tip.2006.881959 · Cited by 3,018 · see citing works
An information fidelity criterion for image quality assessment using natural scene statistics
Sheikh, H. R., Bovik, A. C., & de Veciana, G. (2005) · IEEE Transactions on Image Processing · doi:10.1109/tip.2005.859389 · Cited by 1,399 · see citing works
Contrast masking in human vision
Legge, G. E., & Foley, J. M. (1980) · Journal of the Optical Society of America · doi:10.1364/josa.70.001458 · Cited by 1,188 · see citing works
The effects of a visual fidelity criterion of the encoding of images
Mannos, J., & Sakrison, D. (1974) · IEEE Transactions on Information Theory · doi:10.1109/tit.1974.1055250 · Cited by 1,063 · see citing works
Video quality assessment based on structural distortion measurement
Wang, Z., Lu, L., & Bovik, A. C. (2004) · Signal Processing: Image Communication · doi:10.1016/s0923-5965(03)00076-6 · Cited by 1,024 · see citing works
Graham, N. (1989) · Oxford University Press eBooks · doi:10.1093/acprof:oso/9780195051544.001.0001 · Cited by 959 · see citing works
Multiscale structural similarity for image quality assessment
Wang, Z. (2025) · doi:10.57702/c0fj14hf · Cited by 867 · see citing works
Image quality assessment based on a degradation model
Damera-Venkata, N., Kite, T. D., Geisler, W. S., Evans, B. L., & Bovik, A. C. (2000) · IEEE Transactions on Image Processing · doi:10.1109/83.841940 · Cited by 808 · see citing works
Digital images and human vision
Null, C. H., & Watson, A. B. (1994) · Choice Reviews Online · doi:10.5860/choice.31-5492 · Cited by 657 · see citing works
Wavelet filter evaluation for image compression
Villasenor, J. D., Belzer, B. J., & Liao, J. (1995) · IEEE Transactions on Image Processing · doi:10.1109/83.403412 · Cited by 607 · see citing works
Visibility of wavelet quantization noise
Watson, A. B., Yang, G. Y., Solomon, J. A., & Villasenor, J. D. (1997) · IEEE Transactions on Image Processing · doi:10.1109/83.605413 · Cited by 562 · see citing works
Contrast constancy: deblurring in human vision by spatial frequency channels.
Georgeson, M. A., & Sullivan, G. D. (1975) · The Journal of Physiology · doi:10.1113/jphysiol.1975.sp011162 · Cited by 546 · see citing works
Model of visual contrast gain control and pattern masking
Watson, A. B., & Solomon, J. A. (1997) · Journal of the Optical Society of America A · doi:10.1364/josaa.14.002379 · Cited by 472 · see citing works
Teo, P. C., & Heeger, D. J. (2002) · Proceedings of 1st International Conference on Image Processing · doi:10.1109/icip.1994.413502 · Cited by 471 · see citing works
(1993) · Cited by 466 · see citing works
Schyns, P. G., & Oliva, A. (1999) · Cognition · doi:10.1016/s0010-0277(98)00069-9 · Cited by 448 · see citing works
Grating contrast: Discrimination may be better than detection
Nachmias, J., & Sansbury, R. V. (1974) · Vision Research · doi:10.1016/0042-6989(74)90175-8 · Cited by 395 · see citing works
The cortex transform: Rapid computation of simulated neural images
Watson, A. B. (1987) · Computer Vision Graphics and Image Processing · doi:10.1016/s0734-189x(87)80184-6 · Cited by 392 · see citing works
Perceptual quality metrics applied to still image compression
Eckert, M. P., & Bradley, A. P. (1998) · Signal Processing · doi:10.1016/s0165-1684(98)00124-8 · Cited by 343 · see citing works
Objective picture quality scale (PQS) for image coding
Miyahara, M., Kotani, K., & Algazi, V. R. (1998) · IEEE Transactions on Communications · doi:10.1109/26.718563 · Cited by 335 · see citing works
A VISUAL DISCRIMINATION MODEL FOR IMAGING SYSTEM DESIGN AND EVALUATION
Lubin, J. S. (1995) · WORLD SCIENTIFIC eBooks · doi:10.1142/9789812831200_0010 · Cited by 326 · see citing works
An SVD-based grayscale image quality measure for local and global assessment
Shnayderman, A., Gusev, A., & Eskicioğlu, A. M. (2006) · IEEE Transactions on Image Processing · doi:10.1109/tip.2005.860605 · Cited by 323 · see citing works
Non-linear projection of the retinal image in a wide-angle schematic eye.
Drasdo, N., & Fowler, C. W. (1974) · British Journal of Ophthalmology · doi:10.1136/bjo.58.8.709 · Cited by 306 · see citing works
Translation Insensitive Image Similarity in Complex Wavelet Domain
Wang, Z., & Simoncelli, E. P. (2006) · IEEE International Conference on Acoustics Speech and Signal Processing · doi:10.1109/icassp.2005.1415469 · Cited by 286 · see citing works
A Standard Default Color Space for the Internet - sRGB
Stokes, M. (2005) · Cited by 275 · see citing works
A distortion measure for blocking artifacts in images based on human visual sensitivity
Karunasekera, S. A., & Kingsbury, N. G. (1995) · IEEE Transactions on Image Processing · doi:10.1109/83.388074 · Cited by 270 · see citing works
Spatial frequency, phase, and the contrast of natural images
Bex, P. J., & Makous, W. L. (2002) · Journal of the Optical Society of America A · doi:10.1364/josaa.19.001096 · Cited by 268 · see citing works
A Visual Model Weighted Cosine Transform for Image Compression and Quality Assessment
Nill, N. B. (1985) · IRE Transactions on Communications Systems · doi:10.1109/tcom.1985.1096337 · Cited by 247 · see citing works
The Standard Deviation of Luminance as a Metric for Contrast in Random-Dot Images
Moulden, B., Kingdom, F. A. A., & Gatley, L. F. (1990) · Perception · doi:10.1068/p190079 · Cited by 164 · see citing works
Mitsa, T., & Varkur, K. L. (1993) · IEEE International Conference on Acoustics Speech and Signal Processing · doi:10.1109/icassp.1993.319807 · Cited by 154 · see citing works
A wavelet visible difference predictor
Bradley, A. P. (1999) · IEEE Transactions on Image Processing · doi:10.1109/83.760338 · Cited by 150 · see citing works
Picture Quality Prediction Based on a Visual Model
Lukas, F., & Budrikis, Z. L. (1982) · IEEE Transactions on Communications · doi:10.1109/tcom.1982.1095616 · Cited by 140 · see citing works
An image quality assessment method based on perception of structural information
Carnec, M., Callet, P. L., & Barba, D. (2004) · Proceedings - International Conference on Image Processing · doi:10.1109/icip.2003.1247212 · Cited by 131 · see citing works
Color image fidelity metrics evaluated using image distortion maps
Zhang, X., & Wandell, B. A. (1998) · Signal Processing · doi:10.1016/s0165-1684(98)00125-x · Cited by 117 · see citing works
Brady, N. P., & Field, D. J. (1995) · Vision Research · doi:10.1016/0042-6989(94)00172-i · Cited by 115 · see citing works
Perceptual image quality based on a multiple channel HVS model
Westen, S. J. P., Lagendijk, R. L., & Biemond, J. (2002) · International Conference on Acoustics, Speech, and Signal Processing · doi:10.1109/icassp.1995.479964 · Cited by 96 · see citing works
Lambrecht, C. J. V. D. B. (2002) · IEEE International Conference on Acoustics Speech and Signal Processing · doi:10.1109/icassp.1996.547739 · Cited by 94 · see citing works
Dynamic contrast-based quantization for lossy wavelet image compression
Chandler, D. M., & Hemami, S. S. (2005) · IEEE Transactions on Image Processing · doi:10.1109/tip.2004.841196 · Cited by 82 · see citing works
Self-citationAn overview of the visual optimization tools in JPEG 2000
Zeng, W., Daly, S. J., & Lei, S. (2002) · Signal Processing Image Communication · doi:10.1016/s0923-5965(01)00029-7 · Cited by 76 · see citing works
Contrast sensitivity to patch stimuli: Effects of spatial bandwidth and temporal presentation
Young, G. M., Goldstein, R. B., Peli, E., et al. (1993) · Spatial Vision · doi:10.1163/156856893x00018 · Cited by 74 · see citing works
Chandler, D. M., & Hemami, S. S. (2003) · Journal of the Optical Society of America A · doi:10.1364/josaa.20.001164 · Cited by 66 · see citing works
Self-citationApplication of a noise-adaptive contrast sensitivity function to image data compression
Daly, S. J. (1990) · Optical Engineering · doi:10.1117/12.55666 · Cited by 62 · see citing works
An automatic image quality assessment technique incorporating higher level perceptual factors
Osberger, W. M., Bergmann, N. W., & Maeder, A. J. (2002) · Proceedings - International Conference on Image Processing · doi:10.1109/icip.1998.727227 · Cited by 61 · see citing works
Poynton, C. A. (1998) · Human Vision and Electronic Imaging Conference · Cited by 59 · see citing works
Perceptual characterization of images degraded by blur and noise: experiments
Kayargadde, V., & Martens, J.-B. (1996) · Journal of the Optical Society of America A · doi:10.1364/josaa.13.001166 · Cited by 59 · see citing works
Visual fidelity and perceived quality: toward comprehensive metrics
WINKLER, S. S. (2001) · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · doi:10.1117/12.429540 · Cited by 56 · see citing works
A transducer model for contrast perceptio
Cannon, M. W. (1991) · Vision Research · doi:10.1016/s0042-6989(05)80001-x · Cited by 55 · see citing works
Image quality: a multidimensional problem
Ahumada, A. J., & Null, C. H. (1993) · Cited by 54 · see citing works
Poynton, C. A. (1998) · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · doi:10.1117/12.320126 · Cited by 54 · see citing works
Ramos, M. G., & Hemami, S. S. (2001) · Journal of the Optical Society of America A · doi:10.1364/josaa.18.002385 · Cited by 54 · see citing works
Self-citationA perceptual distortion metric for digital color images
WINKLER, S. S. (2002) · Proceedings - International Conference on Image Processing · doi:10.1109/icip.1998.999029 · Cited by 50 · see citing works
Perceptual characterization of images degraded by blur and noise: model
Kayargadde, V., & Martens, J.-B. (1996) · Journal of the Optical Society of America A · doi:10.1364/josaa.13.001178 · Cited by 47 · see citing works
Sensitivity to contrast histogram differences in synthetic wavelet-textures
Kingdom, F. A. A., Hayes, A., & Field, D. J. (2001) · Vision Research · doi:10.1016/s0042-6989(00)00284-4 · Cited by 47 · see citing works
Image quality assessment metrics based on multi-scale edge presentation
Zhai, G., Zhang, W., Yang, X., et al. (2006) · doi:10.1109/sips.2005.1579888 · Cited by 44 · see citing works
Effects of spatial correlations and global precedence on the visual fidelity of distorted images
Chandler, D. M., Lim, K. H., & Hemami, S. S. (2006) · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · doi:10.1117/12.655442 · Cited by 43 · see citing works
Self-citationSupra-threshold perceptual image coding
Pappas, T. N., Michel, T. A., & Hinds, R. O. (2002) · Proceedings - International Conference on Image Processing · doi:10.1109/icip.1996.559477 · Cited by 41 · see citing works
Additivity models for suprathreshold distortion in quantized wavelet-coded images
Chandler, D. M., & Hemami, S. S. (2002) · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · doi:10.1117/12.469507 · Cited by 37 · see citing works
Self-citationSuprathreshold image compression based on contrast allocation and global precedence
Chandler, D. M., & Hemami, S. S. (2003) · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · doi:10.1117/12.477772 · Cited by 29 · see citing works
Self-citationContrast matching of two-dimensional compound gratings
Tiippana, K. M., Näsänen, R., & Rovamo, J. M. (1994) · Vision Research · doi:10.1016/0042-6989(94)90298-4 · Cited by 26 · see citing works
Chandler, D. M., Dykes, N. L., & Hemami, S. S. (2005) · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · doi:10.1117/12.595614 · Cited by 25 · see citing works
Self-citationImage quality measurement using the Haar wavelet
Lai, Y., & Kuo, C. ‐. J. (1997) · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · doi:10.1117/12.292789 · Cited by 24 · see citing works
Visual quality assessment using a contrast gain control model
WINKLER, S. S. (1999) · IEEE International Workshop on Multimedia Signal Processing (MMSP) · doi:10.1109/mmsp.1999.793905 · Cited by 20 · see citing works
A comparison of image quality metric performances under practical conditions
Zampolo, R. F., & Seara, R. (2005) · Proceedings - International Conference on Image Processing · doi:10.1109/icip.2005.1530611 · Cited by 16 · see citing works
Low-complexity, efficient 9/7 wavelet filters implementation
Martina, M., & Masera, G. (2005) · Proceedings - International Conference on Image Processing · doi:10.1109/icip.2005.1530563 · Cited by 14 · see citing works
Spatial quantization via local texture masking
Gaubatz, M. D., Chandler, D. M., & Hemami, S. S. (2005) · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · doi:10.1117/12.597508 · Cited by 12 · see citing works
Self-citationDigital watermarking using local contrast-based texture masking
Masry, M. A., Chandler, D. M., & Hemami, S. S. (2004) · Asilomar Conference on Signals, Systems and Computers (ACSSC) · doi:10.1109/acssc.2003.1292253 · Cited by 12 · see citing works
Self-citationDistortion measure for blocking artifacts in images based on human visual sensitivity
Karunasekera, S. A., & Kingsbury, N. (1993) · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · doi:10.1117/12.157966 · Cited by 8 · see citing works
Principles of neural shape coding in area V2
Willmore, B. D. B., Prenger, R., & Gallant, J. L. (2005) · Journal of Vision · doi:10.1167/5.8.82 · Cited by 2 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Information content weighting for perceptual image quality assessment
Wang, Z., & Li, Q. (2011) · IEEE Transactions on Image Processing · doi:10.1109/tip.2010.2092435 · Cited by 1,304 · see citing works
Image database TID2013: Peculiarities, results and perspectives
Ponomarenko, N., Jin, L., Ieremeiev, O., Lukin, V., Egiazarian, K., Astola, J., Vozel, B., Chehdi, K., Carli, M., Battisti, F., et al. (2015) · Signal Processing: Image Communication · doi:10.1016/j.image.2014.10.009 · Cited by 1,241 · see citing works
Waterloo Exploration Database: New Challenges for Image Quality Assessment Models
Ma, K., Duanmu, Z., Wu, Q., Wang, Z., Yong, H., Li, H., & Zhang, L. (2017) · IEEE Transactions on Image Processing · doi:10.1109/tip.2016.2631888 · Cited by 789 · see citing works
Blind Prediction of Natural Video Quality
Saad, M. A., Bovik, A. C., & Charrier, C. (2014) · IEEE Transactions on Image Processing · doi:10.1109/tip.2014.2299154 · Cited by 471 · see citing works
Video Quality Assessment by Reduced Reference Spatio-Temporal Entropic Differencing
Soundararajan, R., & Bovik, A. C. (2013) · IEEE Transactions on Circuits and Systems for Video Technology · doi:10.1109/tcsvt.2012.2214933 · Cited by 368 · see citing works
RRED Indices: Reduced Reference Entropic Differencing for Image Quality Assessment
Soundararajan, R., & Bovik, A. C. (2012) · IEEE Transactions on Image Processing · doi:10.1109/tip.2011.2166082 · Cited by 337 · see citing works
Reduced-Reference Image Quality Assessment Using Divisive Normalization-Based Image Representation
Li, Q., & Wang, Z. (2009) · IEEE Journal of Selected Topics in Signal Processing · doi:10.1109/jstsp.2009.2014497 · Cited by 323 · see citing works
A survey of image quality measures
Thung, K.-H., & Raveendran, P. (2009) · 2009 International Conference for Technical Postgraduates (TECHPOS) · doi:10.1109/techpos.2009.5412098 · Cited by 217 · see citing works
Learning to generate images with perceptual similarity metrics
Snell, J., Ridgeway, K., Liao, R., Roads, B. D., Mozer, M. C., & Zemel, R. S. (2017) · 2017 IEEE International Conference on Image Processing (ICIP) · doi:10.1109/icip.2017.8297089 · Cited by 186 · see citing works
ViS3: an algorithm for video quality assessment via analysis of spatial and spatiotemporal slices
Vu, P. V., & Chandler, D. M. (2014) · Journal of Electronic Imaging · doi:10.1117/1.jei.23.1.013016 · Cited by 185 · see citing works
Self-citationA spatiotemporal most-apparent-distortion model for video quality assessment
Vu, P. V., Vu, C. T., & Chandler, D. M. (2011) · 2011 18th IEEE International Conference on Image Processing · doi:10.1109/icip.2011.6116171 · Cited by 180 · see citing works
Self-citationVideo Quality Pooling Adaptive to Perceptual Distortion Severity
Park, J., Seshadrinathan, K., Lee, S., & Bovik, A. C. (2013) · IEEE Transactions on Image Processing · doi:10.1109/tip.2012.2219551 · Cited by 119 · see citing works
Zhang, Y., Moorthy, A. K., Chandler, D. M., & Bovik, A. C. (2014) · Signal Processing: Image Communication · doi:10.1016/j.image.2014.05.004 · Cited by 102 · see citing works
Self-citationDesign of Linear Equalizers Optimized for the Structural Similarity Index
Channappayya, S. S., Bovik, A. C., Caramanis, C., & Heath, R. W. (2008) · IEEE Transactions on Image Processing · doi:10.1109/tip.2008.921328 · Cited by 98 · see citing works
Survey on QoE Assessment Approach for Network Service
Yang, M., Wang, S., Calheiros, R. N., & Yang, F. (2018) · IEEE Access · doi:10.1109/access.2018.2867253 · Cited by 54 · see citing works
Stochastic Image Denoising by Sampling from the Posterior Distribution
Kawar, B., Vaksman, G., & Elad, M. (2021) · 2021 IEEE/CVF International Conference on Computer Vision Workshops (ICCVW) · doi:10.1109/iccvw54120.2021.00213 · Cited by 42 · see citing works
An NFV-Based Video Quality Assessment Method over 5G Small Cell Networks
Kourtis, M.-A., Koumaras, H., Xilouris, G., & Liberal, F. (2017) · IEEE MultiMedia · doi:10.1109/mmul.2017.265091534 · Cited by 22 · see citing works
- Authors
- Chandler, D. M., & Hemami, S. S.
- Affiliations
- Oklahoma State University (US)
- Cornell University (US)
- ORCID
- Chandler, D.M.
- Venue
- IEEE Transactions on Image Processing
- Published
- 2007-09
- Volume
- 16
- Issue
- 9
- Pages
- 2284-2298
- ISSN
- 1057-7149 (ISSN-L)
- OpenAlex
- W2009272644
- Semantic Scholar
- 25efdeaaafa7ac8e3b305d3575fe2d241db1a361
- Cited by
- 1,147
- References
- 75
- Citations by year
- 2026: 13 · 2025: 15 · 2024: 28 · 2023: 26 · 2022: 48 · 2021: 64 · 2020: 53 · 2019: 64 · 2018: 91 · 2017: 92 · 2016: 99 · 2015: 90 · 2014: 106 · 2013: 91 · 2012: 86
- FWCI
- 43.73
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- IEEE Transactions on Image Processing (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Image and Video Quality Assessment
- Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Image Retrieval and Classification Techniques
- Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Image and Signal Denoising Methods
- Keywords
- image quality metrics, visual fidelity, human visual system, visual masking, contrast threshold, distortion detection, perceived contrast, global precedence, natural images, low computational complexity
- MeSH terms
- Algorithms, Humans, Image Enhancement, Image Interpretation, Computer-Assisted, Sensitivity and Specificity, Visual Perception, Reproducibility of Results, Biomimetics
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.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review