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GaussianMarker: Uncertainty-Aware Copyright Protection of 3D Gaussian Splatting

Neural Information Processing Systems

However, existing watermarking methods for meshes, point clouds, and implicit radiance fields cannot be directly applied to 3DGS models, as 3DGS models use explicit 3D Gaussians with distinct structures and do not rely on neural networks. Naively embedding the watermark on a pre-trained 3DGS can cause obvious distortion in rendered images. In our work, we propose an uncertainty-based method that constrains the perturbation of model parameters to achieve invisible watermarking for 3DGS.


Break the Tie: Learning Cluster-Customized Category Relationships for Categorical Data Clustering

Zhao, Mingjie, Huang, Zhanpei, Lu, Yang, Li, Mengke, Zhang, Yiqun, Su, Weifeng, Cheung, Yiu-ming

arXiv.org Artificial Intelligence

Categorical attributes with qualitative values are ubiquitous in cluster analysis of real datasets. Unlike the Euclidean distance of numerical attributes, the categorical attributes lack well-defined relationships of their possible values (also called categories interchangeably), which hampers the exploration of compact categorical data clusters. Although most attempts are made for developing appropriate distance metrics, they typically assume a fixed topological relationship between categories when learning distance metrics, which limits their adaptability to varying cluster structures and often leads to suboptimal clustering performance. This paper, therefore, breaks the intrinsic relationship tie of attribute categories and learns customized distance metrics suitable for flexibly and accurately revealing various cluster distributions. As a result, the fitting ability of the clustering algorithm is significantly enhanced, benefiting from the learnable category relationships. Moreover, the learned category relationships are proved to be Euclidean distance metric-compatible, enabling a seamless extension to mixed datasets that include both numerical and categorical attributes. Comparative experiments on 12 real benchmark datasets with significance tests show the superior clustering accuracy of the proposed method with an average ranking of 1.25, which is significantly higher than the 5.21 ranking of the current best-performing method. Code and extended version with detailed proofs are provided below.


Moving Matter: Using a Single, Simple Robot to Reconfigure a Connected Set of Building Blocks

Garcia, Javier, Friemel, Jonas, Kosfeld, Ramin, Yannuzzi, Michael, Kramer, Peter, Rieck, Christian, Scheffer, Christian, Schmidt, Arne, Kube, Harm, Biediger, Dan, Fekete, Sándor P., Becker, Aaron T.

arXiv.org Artificial Intelligence

We implement and evaluate different methods for the reconfiguration of a connected arrangement of tiles into a desired target shape, using a single active robot that can move along the tile structure. This robot can pick up, carry, or drop off one tile at a time, but it must maintain a single connected configuration at all times. Becker et al. (CCCG 2025) recently proposed an algorithm that uses histograms as canonical intermediate configurations, guaranteeing performance within a constant factor of the optimal solution if the start and target configuration are well-separated. We implement and evaluate this algorithm, both in a simulated and practical setting, using an inchworm type robot to compare it with two existing heuristic algorithms.


Efficient Learning of Balanced Signed Graphs via Sparse Linear Programming

Yokota, Haruki, Higashi, Hiroshi, Tanaka, Yuichi, Cheung, Gene

arXiv.org Artificial Intelligence

Signed graphs are equipped with both positive and negative edge weights, encoding pairwise correlations as well as anti-correlations in data. A balanced signed graph is a signed graph with no cycles containing an odd number of negative edges. Laplacian of a balanced signed graph has eigenvectors that map via a simple linear transform to ones in a corresponding positive graph Laplacian, thus enabling reuse of spectral filtering tools designed for positive graphs. We propose an efficient method to learn a balanced signed graph Laplacian directly from data. Specifically, extending a previous linear programming (LP) based sparse inverse covariance estimation method called CLIME, we formulate a new LP problem for each Laplacian column $i$, where the linear constraints restrict weight signs of edges stemming from node $i$, so that nodes of same / different polarities are connected by positive / negative edges. Towards optimal model selection, we derive a suitable CLIME parameter $ρ$ based on a combination of the Hannan-Quinn information criterion and a minimum feasibility criterion. We solve the LP problem efficiently by tailoring a sparse LP method based on ADMM. We theoretically prove local solution convergence of our proposed iterative algorithm. Extensive experimental results on synthetic and real-world datasets show that our balanced graph learning method outperforms competing methods and enables reuse of spectral filters, wavelets, and graph convolutional nets (GCN) constructed for positive graphs.


GaussianMarker: Uncertainty-Aware Copyright Protection of 3D Gaussian Splatting

Neural Information Processing Systems

However, existing watermarking methods for meshes, point clouds, and implicit radiance fields cannot be directly applied to 3DGS models, as 3DGS models use explicit 3D Gaussians with distinct structures and do not rely on neural networks. Naively embedding the watermark on a pre-trained 3DGS can cause obvious distortion in rendered images. In our work, we propose an uncertainty- based method that constrains the perturbation of model parameters to achieve invisible watermarking for 3DGS. We conduct extensive experiments on the Blender, LLFF, and MipNeRF-360 datasets to validate the effectiveness of our proposed method, demonstrating state-of-the-art performance on both message decoding accuracy and view synthesis quality.


Review for NeurIPS paper: Dynamic Regret of Policy Optimization in Non-Stationary Environments

Neural Information Processing Systems

Weaknesses: (1) The paper assumes a full-information reward feedback, which can be hardly thought as a realistic assumption. Instead, it would be much appreciated to consider the bandit feedback as what [1] does. This is undesired in practice. There are some recent efforts in removing such dependency [2,3]. The basic idea is to run another meta bandits algorithm for selecting the optimal parameter.


Asynchronous Federated Clustering with Unknown Number of Clusters

Zhang, Yunfan, Zhang, Yiqun, Lu, Yang, Li, Mengke, Chen, Xi, Cheung, Yiu-ming

arXiv.org Artificial Intelligence

Federated Clustering (FC) is crucial to mining knowledge from unlabeled non-Independent Identically Distributed (non-IID) data provided by multiple clients while preserving their privacy. Most existing attempts learn cluster distributions at local clients, and then securely pass the desensitized information to the server for aggregation. However, some tricky but common FC problems are still relatively unexplored, including the heterogeneity in terms of clients' communication capacity and the unknown number of proper clusters $k^*$. To further bridge the gap between FC and real application scenarios, this paper first shows that the clients' communication asynchrony and unknown $k^*$ are complex coupling problems, and then proposes an Asynchronous Federated Cluster Learning (AFCL) method accordingly. It spreads the excessive number of seed points to the clients as a learning medium and coordinates them across the clients to form a consensus. To alleviate the distribution imbalance cumulated due to the unforeseen asynchronous uploading from the heterogeneous clients, we also design a balancing mechanism for seeds updating. As a result, the seeds gradually adapt to each other to reveal a proper number of clusters. Extensive experiments demonstrate the efficacy of AFCL.


Efficient Learning of Balanced Signed Graphs via Iterative Linear Programming

Yokota, Haruki, Higashi, Hiroshi, Tanaka, Yuichi, Cheung, Gene

arXiv.org Artificial Intelligence

Signed graphs are equipped with both positive and negative edge weights, encoding pairwise correlations as well as anti-correlations in data. A balanced signed graph has no cycles of odd number of negative edges. Laplacian of a balanced signed graph has eigenvectors that map simply to ones in a similarity-transformed positive graph Laplacian, thus enabling reuse of well-studied spectral filters designed for positive graphs. We propose a fast method to learn a balanced signed graph Laplacian directly from data. Specifically, for each node $i$, to determine its polarity $\beta_i \in \{-1,1\}$ and edge weights $\{w_{i,j}\}_{j=1}^N$, we extend a sparse inverse covariance formulation based on linear programming (LP) called CLIME, by adding linear constraints to enforce ``consistent" signs of edge weights $\{w_{i,j}\}_{j=1}^N$ with the polarities of connected nodes -- i.e., positive/negative edges connect nodes of same/opposing polarities. For each LP, we adapt projections on convex set (POCS) to determine a suitable CLIME parameter $\rho > 0$ that guarantees LP feasibility. We solve the resulting LP via an off-the-shelf LP solver in $\mathcal{O}(N^{2.055})$. Experiments on synthetic and real-world datasets show that our balanced graph learning method outperforms competing methods and enables the use of spectral filters and graph convolutional networks (GCNs) designed for positive graphs on signed graphs.


Elon Musk's X Is Spreading Deepfakes of Kamala Harris

Mother Jones

Deepfakes of Vice President Kamala Harris are proliferating on X.Photo illustration; Rafael Henrique/ZUMA For the second time in less than two weeks, a doctored video of Vice President Kamala Harris has spread widely on Elon Musk's social media platform X. A video known as a "deepfake" that was posted on X on Saturday appears to show Harris repeating herself over and over again, using a crude audio rendering made to seem like Harris is struggling to finish a complete sentence. The altered video uses footage from an appearance by Harris and President Joe Biden following Friday's historic prisoner swap that freed Wall Street Journal reporter Evan Gershkovich and others. The video is obviously manipulated and easily debunked by viewing the unaltered footage (you can watch that here at about the 1:30 mark), which shows Harris speaking smoothly, without repeating the same words and phrases as portrayed in the doctored video. The video, whose origin is unclear, was posted by Trump himself on Truth Social on Saturday, accompanied by a rant in which he calls Harris "DUMB!" and "extremely Low IQ."


Interpretable Lightweight Transformer via Unrolling of Learned Graph Smoothness Priors

Do, Tam Thuc, Eftekhar, Parham, Hosseini, Seyed Alireza, Cheung, Gene, Chou, Philip

arXiv.org Artificial Intelligence

We build interpretable and lightweight transformer-like neural networks by unrolling iterative optimization algorithms that minimize graph smoothness priors -- the quadratic graph Laplacian regularizer (GLR) and the $\ell_1$-norm graph total variation (GTV) -- subject to an interpolation constraint. The crucial insight is that a normalized signal-dependent graph learning module amounts to a variant of the basic self-attention mechanism in conventional transformers. Unlike "black-box" transformers that require learning of large key, query and value matrices to compute scaled dot products as affinities and subsequent output embeddings, resulting in huge parameter sets, our unrolled networks employ shallow CNNs to learn low-dimensional features per node to establish pairwise Mahalanobis distances and construct sparse similarity graphs. At each layer, given a learned graph, the target interpolated signal is simply a low-pass filtered output derived from the minimization of an assumed graph smoothness prior, leading to a dramatic reduction in parameter count. Experiments for two image interpolation applications verify the restoration performance, parameter efficiency and robustness to covariate shift of our graph-based unrolled networks compared to conventional transformers.