forward
Local Linear Convergence of Forward--Backward under Partial Smoothness
In this paper, we consider the Forward--Backward proximal splitting algorithm to minimize the sum of two proper closed convex functions, one of which having a Lipschitz continuous gradient and the other being partly smooth relatively to an active manifold $\mathcal{M}$. We propose a generic framework in which we show that the Forward--Backward (i) correctly identifies the active manifold $\mathcal{M}$ in a finite number of iterations, and then (ii) enters a local linear convergence regime that we characterize precisely. This gives a grounded and unified explanation to the typical behaviour that has been observed numerically for many problems encompassed in our framework, including the Lasso, the group Lasso, the fused Lasso and the nuclear norm regularization to name a few. These results may have numerous applications including in signal/image processing processing, sparse recovery and machine learning.
Local Linear Convergence of Forward--Backward under Partial Smoothness
In this paper, we consider the Forward--Backward proximal splitting algorithm to minimize the sum of two proper closed convex functions, one of which having a Lipschitz continuous gradient and the other being partly smooth relatively to an active manifold \mathcal{M} . We propose a generic framework in which we show that the Forward--Backward (i) correctly identifies the active manifold \mathcal{M} in a finite number of iterations, and then (ii) enters a local linear convergence regime that we characterize precisely. This gives a grounded and unified explanation to the typical behaviour that has been observed numerically for many problems encompassed in our framework, including the Lasso, the group Lasso, the fused Lasso and the nuclear norm regularization to name a few. These results may have numerous applications including in signal/image processing processing, sparse recovery and machine learning.
Probabilistic Inference with Generating Functions for Poisson Latent Variable Models
Graphical models with latent count variables arise in a number of fields. Standard exact inference techniques such as variable elimination and belief propagation do not apply to these models because the latent variables have countably infinite support. As a result, approximations such as truncation or MCMC are employed. We present the first exact inference algorithms for a class of models with latent count variables by developing a novel representation of countably infinite factors as probability generating functions, and then performing variable elimination with generating functions. Our approach is exact, runs in pseudo-polynomial time, and is much faster than existing approximate techniques. It leads to better parameter estimates for problems in population ecology by avoiding error introduced by approximate likelihood computations.
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Local Linear Convergence of Forward--Backward under Partial Smoothness
Liang, Jingwei, Fadili, Jalal, Peyré, Gabriel
In this paper, we consider the Forward--Backward proximal splitting algorithm to minimize the sum of two proper closed convex functions, one of which having a Lipschitz continuous gradient and the other being partly smooth relatively to an active manifold $\mathcal{M}$. We propose a generic framework in which we show that the Forward--Backward (i) correctly identifies the active manifold $\mathcal{M}$ in a finite number of iterations, and then (ii) enters a local linear convergence regime that we characterize precisely. This gives a grounded and unified explanation to the typical behaviour that has been observed numerically for many problems encompassed in our framework, including the Lasso, the group Lasso, the fused Lasso and the nuclear norm regularization to name a few. These results may have numerous applications including in signal/image processing processing, sparse recovery and machine learning. Papers published at the Neural Information Processing Systems Conference.
Report sets out 'practical way forward' for the NHS to harness AI
Key proposals include the development of a clear procurement framework for AI systems, to be developed by NHS England and the National Institute for Health and Care Excellence (NICE), to make sure that'complex to use and unintuitive products are not purchased as they could hamper service transformation', argue the report's authors, Eleonora Harwick and Kate Laycock. The research addresses the complexities around data in the NHS, including the quality of information or consistency of collection processes, recommending that NHS England and NICE take into account the'user-friendliness of IT systems' during procurement so that errors in data entry are spotted in real-time. "The NHS will also need to get data right to truly harness the potential of AI in healthcare. This means collecting the right type of data in the right format, increasing its quality and securely granting access to it," the authors argue, putting emphasis on addressing the lack of interoperability.
Robot-Building Lab and Contest at the 1993 National AI Conference
A robot-building lab and contest was held at the Eleventh National Conference on Artificial Intelligence. Teams of three worked day and night for 72 hours to build tabletop autonomous robots of legos, a small microcontroller board, and sensors. The robots then competed head to head in two events. The contest was a chance to learn about building machines that operate in the real world. The lab was in a roped-off area of the main exhibition area.
Anne v.d.L. Gardner
The object is to bring the situation, or problem state, forward from its initial configuration to one satisfying a goal condition. For example, an initial situation might be the placement of chessmen on the board at the beginning of the game; the desired goal, any board configuration that is a checkmate; and the operators, rules for the legal moves in chess. This difference is then used to index the (forward) operator most relevant to reducing the difference. If this especially relevant operator cannot be immediately applied to the present problem state, subgoals are set up to change the problem state so that the relevant operator can be applied. After these subgoals are solved, the relevant operator is applied and the resulting, modified situation becomes a new starting point from which to solve for the original goal.
Mac made intelligent
I should like to lodge a complaint about your editorial standards in the article "An Assessment of Tools for Building Large KB Systems," by William Mettrey, in the winter 1987 [volume 9 number As a primary architect of CRL-Ops and a former KnowledgeCraft class instructor, I had to deal with the general public's misconceptions about forward versus backward chaining systems. Mr. Mettrey's article, in my opinion, is the type which generates the confusion that forward chaining rule systems cannot "backwards chain." This nonsensical view was held by the vast majority of our customers in the KC class. The section on Rule-Based inference implies that backward chaining is done only by Prolog in KC with its statement "by contrast, Knowledge-Craft implements backward chaining by supporting a version of Prolog." Any forward chaining rules system can efficiently implement constrained backward chaining by simply using a goal structure to search for the required knowledge.
Editorial
I am honored by the appointment and look forward to the opportunity to guide the magazine as it begins its third decade of publication. AI Magazine serves the artificial intelligence community in many ways. It is a medium for disseminating information about AI areas and methods to readers across the entire field of AI, as well as to a broad multidisciplinary audience. It is a journal of record for articles on important research and applications advances as well as for meeting reports, reviews, and discussions that illuminate the state of the art and emerging areas. Equally important, it is a forum for sharing visions for the field--perspectives on issues, priorities, and challenges for moving forward.