Minimum HGR correlation principle: From marginals to joint distribution
Minimum HGR correlation principle: From marginals to joint distribution
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最小HGR相关性原理:从边际分布到联合分布
DOI:
10.1109/isit.2015.7282681
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发表时间:
2015
期刊:
影响因子:
--
通讯作者:
David Tse
中科院分区:
文献类型:
--
作者:
Farzan Farnia;Meisam Razaviyayn;Sreeram Kannan;David Tse
Given low order moment information over the random variables X = (X1, X2, ..., Xp) and Y, what distribution minimizes the Hirschfeld-Gebelein-Rényi (HGR) maximal correlation coefficient between X and Y, while remains faithful to the given moments? The answer to this question is important especially in order to fit models over (X, Y) with minimum dependence among the random variables X and Y. In this paper, we investigate this question first in the continuous setting by showing that the jointly Gaussian distribution achieves the minimum HGR correlation coefficient among distributions with the given first and second order moments. Then, we pose a similar question in the discrete scenario by fixing the pairwise marginals of the random variables X and Y. Subsequently, we derive a lower bound for the HGR correlation coefficient over the class of distributions with fixed pairwise marginals. Then we show that this lower bound is tight if there exists a distribution with certain additive structure satisfying the given pairwise marginals. Moreover, the distribution with the additive structure achieves the minimum HGR correlation coefficient. Finally, we conclude by showing that the event of obtaining pairwise marginals containing an additive structured distribution has a positive Lebesgue measure over the probability simplex.