90 likes | 113 Views
This presentation proposes a generalized optimization problem that extends the concept of data compression to other domains such as website layout and forest fires. The problem is formulated and analyzed for three examples, showcasing the tradeoff between resource allocation and event loss. The average statistics in these examples exhibit power law distributions, highlighting the need for highly optimized solutions. This presentation provides insights into the applicability of the generalized framework and raises questions about the optimality of existing designs in the given domains.
E N D
Power Laws, Highly Optimized Tolerance and generalized source coding John Doyle, J.M. Carlson Presented by Sumitra Ganesh
Overview • Propose an optimization problem that is a generalization of the Data Compression (Source coding) problem • Problem is formulated and analyzed for 3 examples : Data compression (DC), Website layout (WWW), Forest Fires (FF)
The PLR optimization problem Probability of event Loss/size associated with event Resource allocated to suppress the size
Data Compression Each source symbol – codeword of Bits.
Web Layout • The sizes are the lengths of the files • The probabilities are determined by user interest in the files • The cost is the average delay that a user experiences in downloading files • Resource limit is on the total number of files
WWW contd Crucial : The resource-loss tradeoff is determined by The resource allocation (separation if document into files) may change influence the hit probability for a given file. Split the one-dimensional file into N regions of equal size and with uniform access probability
Forest Fires • Two-dimensional problem • The losses are the burned areas • The probabilities are determined by the probability of sparks • The cost is the average timber lost in fires • Resource is the density of firebreaks etc.
Comments • Generalized framework : not clear about its applicability • The average statistics seem to obey power laws even though the individual websites were not optimally designed (Why?) • The three examples are explained well