Title
Some recent results on local testing of sparse linear codes
Abstract
We study the local testability of linear codes. Our approach is based on a reformulation of this question in the language of tolerant linearity testing under a non-uniform distribution. We then study the question of linearity testing under non-uniform distributions directly, and give a sufficient criterion for linearity to be tolerantly testable under a given distribution.We show that several natural classes of distributions satisfy this criterion (such as product distributions and low Fourier-bias distributions), thus showing that linearity is tolerantly testable under these distributions. This in turn implies that the corresponding codes are locally testable. For the case of random sparse linear codes, we show the testability and decodability of such codes in the presence of very high noise rates. More precisely, we show that any linear code in F2n which is: - sparse (i.e., has only poly(n) codewords) - unbiased (i.e., each nonzero codeword has Hamming weight in (1/2- n-γ, 1/2 + n-γ for some constant γ ≥ 0) can be locally tested and locally list decoded from (1/2-ε)-fraction errors using only poly(1/ε) queries to the received word. This simultaneously simplifies and strengthens a result of Kaufman and Sudan, who gave a local tester and local (unique) decoder for such codes from some constant fraction of errors. For the case of Dual BCH codes, our algorithms can also be made to run in sublinear time. Building on the methods used for the local algorithms, we also give sub-exponential time algorithms for list-decoding arbitrary unbiased (but not necessarily sparse) linear codes in the high-error regime.
Year
DOI
Venue
2010
10.1007/978-3-642-16367-8_26
Property Testing
Keywords
Field
DocType
tolerant linearity testing,local tester,local testing,linearity testing,constant fraction,non-uniform distribution,random sparse linear code,local testability,local algorithm,linear code,recent result,tolerantly testable,uniform distribution,satisfiability,product distribution,list decoding
Locally decodable code,Hamming code,Discrete mathematics,Low-density parity-check code,Block code,Expander code,BCH code,Reed–Muller code,Linear code,Mathematics
Conference
Volume
ISSN
ISBN
6390
0302-9743
3-642-16366-1
Citations 
PageRank 
References 
0
0.34
23
Authors
2
Name
Order
Citations
PageRank
Swastik Kopparty138432.89
Shubhangi Saraf226324.55