On the Maximum of a Measure of Deviation from Independence Between Discrete Random Variables
Gilula, Zvi ; Schwarz, Gideon
Ann. Probab., Tome 13 (1985) no. 4, p. 314-317 / Harvested from Project Euclid
The squared $n^k$-dimensional Euclidean distance $f_k$ between a given joint distribution of $k$ random variables with values in $1, \cdots, n$ and the joint distribution of independent variables with the same respective marginals has been suggested as a measure of dependence. The following facts are established for $M_k$, the maximum of $f_k$ over all joint distributions for fixed $k$: (1) $M_k$ is attained among the distributions with all $k$ variables equal to a variable $X$ that takes on just two values. (2) For $k \leq 6, M_k = 1/2 - (1/2)^k$ is attained when the distribution of $X$ is $\{1/2, 1/2\}$. (3) For $k \geq 7, M_k$ is not attained at $\{1/2, 1/2\}$ and strictly exceeds $1/2 - (1/2)^k$. (4) For $k \rightarrow \infty$, the distributions of $X$ where $M_k$ is attained approach $\{0, 1\}$, and $M_k \nearrow 1$.
Publié le : 1985-02-14
Classification:  Deviations from independence,  upper bounds,  62H20,  62H05
@article{1176993085,
     author = {Gilula, Zvi and Schwarz, Gideon},
     title = {On the Maximum of a Measure of Deviation from Independence Between Discrete Random Variables},
     journal = {Ann. Probab.},
     volume = {13},
     number = {4},
     year = {1985},
     pages = { 314-317},
     language = {en},
     url = {http://dml.mathdoc.fr/item/1176993085}
}
Gilula, Zvi; Schwarz, Gideon. On the Maximum of a Measure of Deviation from Independence Between Discrete Random Variables. Ann. Probab., Tome 13 (1985) no. 4, pp.  314-317. http://gdmltest.u-ga.fr/item/1176993085/