1.NounLet
b
{\displaystyle \mathbf {b} }
be a vector and define the support
supp
(
b
)
=
{
i
:
b
i
≠
0
}
{\displaystyle \operatorname {supp} (\mathbf {b} )=\{i:\mathbf {b} _{i}\neq 0\}}
where
b
i
{\displaystyle \mathbf {b} _{i}}
is the
i
{\displaystyle i}
th element of
b
{\displaystyle \mathbf {b} }
. Let
b
^
{\displaystyle {\hat {\mathbf {b} }}}
be an estimator for
b
{\displaystyle \mathbf {b} }
. Then sparsistency is the property that the support of the estimator converges to the true support as the number of samples grows to infinity.