Browsing by Subject "Probabilistic logic"

Now showing 1 - 2 of 2

Open Access
Cyclic scheduling for age of information minimization with generate at will status updates
(IEEE, 2024-04-02) Gamgam, Ege Orkun; Akar, Nail; Ulukus, Sennur; Akar, Nail
We study the scheduling problem in a status update system composed of multiple information sources with different service time distributions and weights, for the purpose of minimizing the weighted sum age of information (AoI). In particular, we study open-loop schedulers which rely only on the statistics (specifically, only on the first two moments) of the source service times, in contrast to closed-loop schedulers that also make use of the actual realizations of the service times and the AoI processes in making scheduling decisions. We consider the generate-at-will (GAW) model, and develop an analytical method to calculate the exact AoI for probabilistic and cyclic open-loop schedulers. In both cases, the server initiates the sampling of a source and the ensuing transmission of the update packet from the source to the server in an open-loop manner; either based on a certain probability (probabilistic scheme) or according to a deterministic cyclic pattern (cyclic scheme). We derive the optimum open-loop cyclic scheduling policy in closed form for the specific case of N = 2 sources and propose well-performing heuristic cyclic schedulers for general number of sources, i.e., N > 2. Numerical examples are provided to validate the existing methods.
Open Access
Quadratic signaling with prior mismatch at an encoder and decoder: equilibria, continuity, and robustness properties
(Institute of Electrical and Electronics Engineers, 2022-01-11) Kazikli, E.; Sartas, S.; Gezici, Sinan
We consider communications through a Gaussian noise channel between an encoder and a decoder which have subjective probabilistic models on the source distribution. Although they consider the same cost function, the induced expected costs are misaligned due to their prior mismatch, which requires a game theoretic approach. We consider two approaches: a Nash setup, with no prior commitment, and a Stackelberg solution concept, where the encoder is committed to a given announced policy apriori. We show that the Stackelberg equilibrium cost of the encoder is upper semi continuous, under the Wasserstein metric, as encoder's prior approaches the decoder's prior, and it is also lower semi continuous with Gaussian priors. For the Stackelberg setup, the optimality of affine policies for Gaussian signaling no longer holds under prior mismatch, and thus team-theoretic optimality of linear/affine policies are not robust to perturbations. We provide conditions under which there exist informative Nash and Stackelberg equilibria with affine policies. Finally, we show existence of fully informative Nash and Stackelberg equilibria for the cheap talk problem under an absolute continuity condition.