NP is a problem in the field of computational complexity. P is a set of relatively easy problems, and NP is a set of problems some of which appear to be diabolically hard. Williams is the son of a mother who taught grade school and a father who ran his own construction firm and whose family indoctrinated Williams into one side of a deep Alabamian social divide — the side that roots for Auburn in the annual Auburn-Alabama football game. His father ran the backhoe, and Williams followed behind the bucket, digging out rocks and roots, smoothing the ground, and measuring the grade with a laser level.
In first grade, having scored highly on a standardized test the year before, Williams began taking a class one day a week at a school for gifted children on the opposite side of the county. The next year, the class had a different teacher and the computer was gone, but Williams kept writing Basic programs nonetheless. For three straight years, from 8th through 10th grade, he and a partner won a statewide programming competition, writing in the oft-derided Basic language. They competed as an undersized team, even though the state Technology Fair sponsored an individual competition as well.
After his junior-year introduction to the P vs.
NP problem, Williams was determined to study theoretical computer science in college. He ended up at Cornell University, studying with Juris Hartmanis, a pioneer in complexity theory and a winner of the Turing Award, the Nobel Prize of computer science. Williams also introduced his Yankee classmates to the ardor of Alabamian football fandom, commandeering communal televisions for the annual Auburn-Alabama games. Blum told Williams that he was interested in two topics: k-anonymity — a measure of data privacy — and consciousness.
K-anonymity seemed slightly more tractable, so Williams dove into it.
Arthur-Merlin games: A randomized proof system, and a hierarchy of complexity classes. Andrew Chi-Chih Yao. This program will bring together researchers from both ends of this spectrum, with the aim of bridging this decades-old divide. Very neat. Computer-Simulation Model Theory is an extension of Mathematical Model Theory where instead of mathematical-structures, computer-simulations are replaced, and the activity of reasoning and computing of the reasoner is also simulated in the model. Harry Potter. This paper illustrates the power of Gaussian Elimination by adapting it to the problem of Exact Satisfiability.
Such proofs depend on the calculation of lower bounds — the minimum number of computational steps necessary to solve particular problems. As a potential thesis project, Williams began considering lower bounds on NP-complete problems when solved by computers with extremely limited memory. The hope was that establishing lower bounds in such artificially constrained cases would point the way toward establishing them in the more general case.
His dissertation ended up being an automated technique for proving lower bounds in the context of memory-constrained computing.
That result came from an attempt to bridge a divide within theoretical computer science, between researchers who work on computational complexity and those who design algorithms. CSMT argues that:.
The Polynomial Hierarchy Collapses. This paper illustrates the power of Gaussian Elimination by adapting it to the problem of Exact Satisfiability. Our method shows that Positive instances of 1-in-3 SAT may be reduced to significantly smaller instances of I. We then proceed to define formally the notion of a non-trivial kernel.
For this, we define the problems considered as Constraint Satisfaction Problems. Considering recent advances in Computational Complexity relating to sparsification and existence of non-trivial kernels, we conclude by showing that the method presented here, giving a non-trivial kernel for positive 1-in-3 SAT, implies the existence of a non-trivial kernel for 1-in-3 SAT. No rationality through brute-force slides.
All reasoners described in the most widespread models of a rational reasoner exhibit logical omniscience, what is impossible for finite reasoners real reasoners. The most common strategy for dealing with the problem of logical The most common strategy for dealing with the problem of logical omniscience is to interpret the models using a notion of beliefs different from explicit beliefs. For example, the model could be interpreted as describing the beliefs that the reasoner would hold if the reasoner were able reason indefinitely stable beliefs.
Advances in Computational Complexity Theory cover image. DIMACS - Series in Discrete Mathematics and Theoretical Computer Science. VOLUME THIRTEEN TITLE: "ADVANCES IN COMPUTATIONAL COMPLEXITY THEORY" EDITORS: Jin-Yi Cai Published by the American Mathematical Society .
Then the model would describe maximum rationality, what a finite reasoner can only approach in the limit of a reasoning sequence. This strategy has important consequences to epistemology.
If a finite reasoner can only approach maximum rationality in the limit of a reasoning sequence, then the efficiency of reasoning is epistemically and not only pragmatically relevant. In section 1, I present an argument to this conclusion. In section 2, I discuss the consequences of this conclusion, as, for example, the vindication of the principle 'no rationality through brute-force'. Call admission control CAC , a resource management function, is required to regulate network access to provide the required levels of QoS to emerging services in Fourth Generation 4G mobile networks.
However, CAC is one of the However, CAC is one of the challenging issues for quality of service QoS due to imprecise, uncertain and inaccurate measurements of network data. Although type-1 fuzzy system T1FLS can handle the uncertainties related to imprecise data, it cannot adequately handle new problems posed by the complex nature of data traffic and diversity of the QoS requirements of data users. This is because T1FLS is characterised by precise membership functions. The IT2FLS with fuzzy membership functions can fully cope with uncertainties associated with such dynamic network environments by raising its accuracy for a better performance.
The empirical comparison is made on the designed system with synthetic datasets.
One of the approaches gaining ground in policy design is the implementation of combinations of policy measures as policy packages with the aim of increasing efficiency and effectiveness of the designed policies. In this paper, we describe In this paper, we describe the recent advancements in the developments of a virtual environment for the exploration and analysis of policy packages. The virtual environment uses an agent-based modelling approach for the generation of different configurations of policy measures in the policy packages.
The benefit of using the approach is the proactive and flexible generation of policy packages as the agents can react to the changes that occur and create packages that are more robust.
The system allows faster examination of more alternatives, further exploration of the design space, and testing the effects of changes and uncertainties while formulating policies. The results demonstrate the benefit of using agent-based modelling approaches in the design of complex policies. Which policy first? A network-centric approach for the analysis and ranking of policy measures. In addressing various policy problems, deciding which policy measure to start with given the range of measures available is challenging and essentially involves a process of ranking the alternatives, commonly done using In addressing various policy problems, deciding which policy measure to start with given the range of measures available is challenging and essentially involves a process of ranking the alternatives, commonly done using multicriteria decision analysis MCDA techniques.
In this paper a new methodology for analysis and ranking of policy measures is introduced which combines network analysis and MCDA tools. This methodology not only considers the internal properties of the measures but also their interactions with other potential measures. Ding-Zhu Du. William Cook. Panos M. Alexander Ashikhmin.
Paul W. Ronald L.
Martin Farach-Colton. Regina Y. Simon Thomas. Saugata Basu.
Piyush Gupta. Larry A. David Aldous. Peng-Jun Wan. Home Contact us Help Free delivery worldwide. Free delivery worldwide. Bestselling Series. Harry Potter. Popular Features. New Releases.