Search results for "algoritmit"
showing 10 items of 118 documents
The Max-Product Algorithm Viewed as Linear Data-Fusion: A Distributed Detection Scenario
2019
In this paper, we disclose the statistical behavior of the max-product algorithm configured to solve a maximum a posteriori (MAP) estimation problem in a network of distributed agents. Specifically, we first build a distributed hypothesis test conducted by a max-product iteration over a binary-valued pairwise Markov random field and show that the decision variables obtained are linear combinations of the local log-likelihood ratios observed in the network. Then, we use these linear combinations to formulate the system performance in terms of the false-alarm and detection probabilities. Our findings indicate that, in the hypothesis test concerned, the optimal performance of the max-product a…
Surrogate outcomes and transportability
2019
Identification of causal effects is one of the most fundamental tasks of causal inference. We consider an identifiability problem where some experimental and observational data are available but neither data alone is sufficient for the identification of the causal effect of interest. Instead of the outcome of interest, surrogate outcomes are measured in the experiments. This problem is a generalization of identifiability using surrogate experiments and we label it as surrogate outcome identifiability. We show that the concept of transportability provides a sufficient criteria for determining surrogate outcome identifiability for a large class of queries.
Comparison of Internal Clustering Validation Indices for Prototype-Based Clustering
2017
Clustering is an unsupervised machine learning and pattern recognition method. In general, in addition to revealing hidden groups of similar observations and clusters, their number needs to be determined. Internal clustering validation indices estimate this number without any external information. The purpose of this article is to evaluate, empirically, characteristics of a representative set of internal clustering validation indices with many datasets. The prototype-based clustering framework includes multiple, classical and robust, statistical estimates of cluster location so that the overall setting of the paper is novel. General observations on the quality of validation indices and on t…
Algorithms and Organizing
2022
Abstract Algorithms are a ubiquitous part of organizations as they enable, guide, and restrict organizing at the level of everyday interactions. This essay focuses on algorithms and organizing by reviewing the literature on algorithms in organizations, examining the viewpoint of relationality and relational agency on algorithms and organizing, exploring the properties of algorithms, and concluding what these mean from an organizational communication viewpoint. Algorithms need data to be collected. The data are always biased, and algorithms exclude everything that is not in their code. They define what is seen as important. Their operating principles are opaque, and they are political due to…
Multi-Connectivity in 5G and Beyond Non-Terrestrial Networks
2022
The Fifth Generation (5G) communications systems aim to serve such service classes as Ultra-Reliable Low Latency Communications (URLLC), enhanced Mobile Broadband (eMBB), and massive Machine-Type Communications (mMTC). To meet the growing requirements posed to mobile networks, satellites can be used to complement the Terrestrial Networks (TNs). To increase the efficiency of the satellite communications involved, bandwidth-efficient techniques should be used. Multi- Connectivity (MC) is one such technique. In MC, a User Equipment (UE), for example, a smartphone, can be connected to multiple Next Generation Node Bs (gNBs) simultaneously. In this paper, an adaptive MC activation scheme for thr…
Statistical models and inference for spatial point patterns with intensity-dependent marks
2009
A Simple Indicator Based Evolutionary Algorithm for Set-Based Minmax Robustness
2018
For multiobjective optimization problems with uncertain parameters in the objective functions, different variants of minmax robustness concepts have been defined in the literature. The idea of minmax robustness is to optimize in the worst case such that the solutions have the best objective function values even when the worst case happens. However, the computation of the minmax robust Pareto optimal solutions remains challenging. This paper proposes a simple indicator based evolutionary algorithm for robustness (SIBEA-R) to address this challenge by computing a set of non-dominated set-based minmax robust solutions. In SIBEA-R, we consider the set of objective function values in the worst c…
Interactive Inverse Modeling Based Multiobjective Evolutionary Algorithm
2018
An interactive version of the inverse modeling based multiobjective evolutionary algorithm is presented. Instead of generating a representation of the whole Pareto optimal front, the algorithm aims at producing solutions in the regions where the decision maker is interested in. This is facilitated through an interactive solution process where the decision maker iteratively evaluates a set of solutions shown to her/him and the preference information obtained is used to adapt the search process of the algorithm. peerReviewed
On the convergence of unconstrained adaptive Markov chain Monte Carlo algorithms
2010
The spanning tree based approach for solving the shortest path problem in social graphs
2016
This thesis is devoted to the shortest path problem in social graphs. Social graphs represent individuals and social relationships between them. As for social networking sites, their users are represented as vertices of the social graph, and the relationship which indicates whether two users are friends in the social networking site are represented as edges of the social graph. Therefore, social graphs are widely investigated by sociologists in order to determine rules and properties of various social processes. Analysis of such social graphs may be used in prediction of results of election, or recommendation systems. Calculation of many social graph metrics requires computation of shortest…