The lawsuit, which was filed Thursday, claims that the AI company unlawfully crawls, scrapes, copies, and distributes CNN's content from CNN Digital Platforms and third-party platforms. It also accuses the AI tools of reproducing verbatim copies of its articles, including paywalled stories, in query responses to users. Perplexity's AI tools allegedly have incorrectly attributed hallucinated content to CNN, which the company says in the suit violates its trademark. CNN's lawsuit stands for the proposition that Perplexity, a company valued at tens of billions of dollars, should not be able to steal from entities that create the original content Perplexity exploits, a CNN spokesperson said in a statement to the outlet. The public rely on high quality news journalism reported by human beings to understand their world, which is frequently dangerous and expensive to produce.

The complaint, filed on Thursday, said that Perplexity unlawfully copied thousands of CNN stories, videos and images to power its products and distribute "identical or substantially similar" competing content. CNN is asking for an unspecified amount of monetary damages and a court order blocking Perplexity from violating its intellectual property rights. "CNN's lawsuit stands for the proposition that Perplexity, a company valued at tens of billions of dollars, should not be able to steal from entities that create the original content Perplexity exploits," the Warner Bros-owned news company said in a statement. Anthropic was the first AI company to settle one of these cases last year, agreeing to pay $1.5bn to resolve a class action lawsuit from a group of authors. Perplexity is also facing lawsuits from The New York Times, Reddit and Dow Jones, among others.

Low-dimensional embeddings are widely used as visual summaries of high-dimensional data and to enable downstream scientific discoveries. Yet, popular nonlinear dimension reduction methods, such as t-SNE and UMAP, are often selected based on visual appeal alone and without rigorous quantitative validation. A major reason is that manifold embeddings typically do not provide an out-of-sample map nor an inverse back to the original feature space; this makes held-out validation, the gold standard in supervised learning, all but impossible. To address these challenges, we develop a novel framework, MEDAL (Manifold Embedding Distillation via Autoencoder Learning), which distills a fitted manifold embedding into a reusable encoder--decoder model. MEDAL trains a constrained autoencoder whose bottleneck exactly matches any teacher embedding while the decoder reconstructs the original input; this yields an explicit map for new samples, an approximate inverse, and a pointwise reconstruction-based measure of distortion in the manifold space. This converts static manifold embeddings into models that can be evaluated on held-out data, enabling quantitative validation including comparing different dimension reduction methods as well as hyperparameter tuning. Across multiple benchmark and scientific case studies, we show that MEDAL enables held-out validation to determine optimal manifold embeddings and hyperparameters, reveals biologically coherent regions that are difficult to preserve in two dimensional embeddings, and detects distribution shift when new samples are mapped into a fixed reference manifold. MEDAL provides a general validation wrapper to any existing dimension reduction technique that will improve the rigor and

Last month, Perplexity sought to better compete with the likes of Claude Cowork and get out ahead of Apple's delayed, generative AI-powered version of Siri by bringing Personal Computer to macOS . The AI assistant was previously only available to those on Perplexity's $200 per month Max plan, but now the company has opened it up to all Mac users. The company says everyone can download the new Perplexity macOS app and use Personal Computer for everyday queries, attachments and dictation. Usage is tied to Pro and Max plans' credit limits, Perplexity noted. Personal Computer can run tasks across local files, other apps, the web and Perplexity's own servers, according to the company.

This manuscript contains preprint of a chapter under consideration for inclusion in the forthcoming third edition of {\em Cover and Thomas's Elements of Information Theory}, posted with permission from Wiley. The table of contents EIT-3 ToC of the new edition can be found at: https://docs.google.com/document/d/1L-m4oQEJw1PJhoxBeMwrrBD8S_HmvzMEkPbYvS24980/edit?usp=sharing . For feedback, please contact abbas@ee.stanford.edu Learning and information theory intersect in both model training and the characterization of fundamental performance limits. This manuscript provides a concise and accessible treatment of the first intersection, requiring only basic background in information theory and statistics at the senior undergraduate or first-year graduate level. End-of-chapter exercises make the material well suited for classroom use as well as self-study. The chapter focuses on the role of divergence measures in model training, with examples ranging from linear and logistic regression to autoregressive models, variational autoencoders, diffusion models, generative adversarial networks, and score-based models. It introduces the evidence lower bound (ELBO), $f$\!-divergences, and the Fisher divergence. In particular, the treatment of the generative diffusion model provides a more systematic and explicit derivation than is typical in the literature.

Neural Information Processing Systems http://nips.cc/

Transformers [1] have become one of the most important architectural innovations in deep learning and have enabled many breakthroughs over the past few years. Here we propose a simple network architecture, gMLP, based on MLPs with gating, and show that it can perform as well as Transformers in key language and vision applications. Our comparisons show that self-attention is not critical for Vision Transformers, as gMLP can achieve the same accuracy. For BERT, our model achieves parity with Transformers on pretraining perplexity and is better on some downstream NLP tasks. On finetuning tasks where gMLP performs worse, making the gMLP model substantially larger can close the gap with Transformers. In general, our experiments show that gMLP can scale as well as Transformers over increased data and compute.

Our 8BMoE model achieves stronger pre-training perplexity than its dense counterpart. However, a better perplexity does not always directly translate to downstream performance as demonstrated in Section 4.4. To this end, we compare fine-tuning performance of the 8B dense model and MoE model in Table 1. As shown in the table, our MoE model using expert choice routing consistently outperforms the dense model across the 11 tasks in GLUE and SuperGLUE. We evaluate the downstream task fine-tuning performance by varying the capacity factors.