Semantic Information Pursuit for Multimodal Data Analysis

Lead Research Organisation: University of Oxford
Department Name: Statistics

Abstract

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Publications

10 25 50
 
Title Estimation of Copulas via Maximum Mean Discrepancy 
Description This article deals with robust inference for parametric copula models. Estimation using canonical maximum likelihood might be unstable, especially in the presence of outliers. We propose to use a procedure based on the maximum mean discrepancy (MMD) principle. We derive nonasymptotic oracle inequalities, consistency and asymptotic normality of this new estimator. In particular, the oracle inequality holds without any assumption on the copula family, and can be applied in the presence of outliers or under misspecification. Moreover, in our MMD framework, the statistical inference of copula models for which there exists no density with respect to the Lebesgue measure on [0,1]d, as the Marshall-Olkin copula, becomes feasible. A simulation study shows the robustness of our new procedures, especially compared to pseudo-maximum likelihood estimation. An R package implementing the MMD estimator for copula models is available. Supplementary materials for this article are available online. 
Type Of Material Database/Collection of data 
Year Produced 2022 
Provided To Others? Yes  
URL https://tandf.figshare.com/articles/dataset/Estimation_of_Copulas_via_Maximum_Mean_Discrepancy/19487...
 
Title Estimation of Copulas via Maximum Mean Discrepancy 
Description This article deals with robust inference for parametric copula models. Estimation using canonical maximum likelihood might be unstable, especially in the presence of outliers. We propose to use a procedure based on the maximum mean discrepancy (MMD) principle. We derive nonasymptotic oracle inequalities, consistency and asymptotic normality of this new estimator. In particular, the oracle inequality holds without any assumption on the copula family, and can be applied in the presence of outliers or under misspecification. Moreover, in our MMD framework, the statistical inference of copula models for which there exists no density with respect to the Lebesgue measure on [0,1]d, as the Marshall-Olkin copula, becomes feasible. A simulation study shows the robustness of our new procedures, especially compared to pseudo-maximum likelihood estimation. An R package implementing the MMD estimator for copula models is available. Supplementary materials for this article are available online. 
Type Of Material Database/Collection of data 
Year Produced 2022 
Provided To Others? Yes  
URL https://tandf.figshare.com/articles/dataset/Estimation_of_Copulas_via_Maximum_Mean_Discrepancy/19487...
 
Title UPIQ: Unified Photometric Image Quality dataset 
Description Unified Photometric Image Quality dataset (UPIQ) UPIQ dataset is intended for training and evaluation of full-reference HDR image quality metrics. The dataset contains 84 reference images and 4159 distorted images from four datasets, TID2013 [1] (SDR), LIVE [2] (SDR), Narwaria et al. [3] (HDR) and Korshunov et al. [4] (HDR). Quality scores were obtained by re-aligning existing datasets to a common unified quality scale. This was achieved by collecting additional cross-dataset quality comparisons and re-scaling existing data with a psychometric scaling method. Images in the dataset are represented in absolute photometric and colorimetric units, corresponding to light emitted from a display. [1] Ponomarenko, N., Jin, L., Ieremeiev, O., Lukin, V., Egiazarian, K., Astola, J., Benoit: Image database tid2013: Peculiarities, results and perspectives. Signal Processing: Image Communication 30, 57 - 77 (2015) [2] Sheikh, H., Sabir, M., Bovik, A.: A Statistical Evaluation of Recent Full Reference Image Quality Assessment Algorithms. IEEE Transactions on Image Processing 15(11), 3440-3451 (2006). https://doi.org/10.1109/TIP.2006.881959, http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=1709988 [3] Narwaria, M., P. Da Silva, M., Le Callet, P., Pepion, R.: Tone mapping-based high-dynamic-range image compression: study of optimization criterion and perceptual quality. Optical Engineering 52(10) (2013). https://doi.org/10.1117/1.OE.52.10.102008 [4] Korshunov, P., Hanhart, P., Richter, T., Artusi, A., Mantiuk, R., Ebrahimi, T.: Subjective quality assessment database of HDR images compressed with jpeg xt. In: 2015 Seventh International Workshop on Quality of Multimedia Experience (QoMEX). pp. 1-6 (May 2015). https://doi.org/10.1109/QoMEX.2015.7148119 
Type Of Material Database/Collection of data 
Year Produced 2020 
Provided To Others? Yes  
URL https://www.repository.cam.ac.uk/handle/1810/315373
 
Title UPIQ: Unified Photometric Image Quality dataset (04.2021) 
Description Unified Photometric Image Quality dataset (UPIQ) UPIQ dataset is intended for training and evaluation of full-reference HDR image quality metrics. The dataset contains 84 reference images and 4159 distorted images from four datasets, TID2013 [1] (SDR), LIVE [2] (SDR), Narwaria et al. [3] (HDR) and Korshunov et al. [4] (HDR). Quality scores were obtained by re-aligning existing datasets to a common unified quality scale. This was achieved by collecting additional cross-dataset quality comparisons and re-scaling existing data with a psychometric scaling method. Images in the dataset are represented in absolute photometric and colorimetric units, corresponding to light emitted from a display. This is an updated version of the dataset with the fixed pix_per_deg column. See README.md. [1] Ponomarenko, N., Jin, L., Ieremeiev, O., Lukin, V., Egiazarian, K., Astola, J., Benoit: Image database tid2013: Peculiarities, results and perspectives. Signal Processing: Image Communication 30, 57 - 77 (2015) [2] Sheikh, H., Sabir, M., Bovik, A.: A Statistical Evaluation of Recent Full Reference Image Quality Assessment Algorithms. IEEE Transactions on Image Processing 15(11), 3440-3451 (2006). https://doi.org/10.1109/TIP.2006.881959, http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=1709988 [3] Narwaria, M., P. Da Silva, M., Le Callet, P., Pepion, R.: Tone mapping-based high-dynamic-range image compression: study of optimization criterion and perceptual quality. Optical Engineering 52(10) (2013). https://doi.org/10.1117/1.OE.52.10.102008 [4] Korshunov, P., Hanhart, P., Richter, T., Artusi, A., Mantiuk, R., Ebrahimi, T.: Subjective quality assessment database of HDR images compressed with jpeg xt. In: 2015 Seventh International Workshop on Quality of Multimedia Experience (QoMEX). pp. 1-6 (May 2015). https://doi.org/10.1109/QoMEX.2015.7148119 
Type Of Material Database/Collection of data 
Year Produced 2021 
Provided To Others? Yes  
URL https://www.repository.cam.ac.uk/handle/1810/321331