where
ai=aii and
for any
i{1,2,,n},
ρ(
B) and
denote the Perron root of the nonnegative matrix
B=[bij] satisfying
aij,ajibij for all
i,j{1,2,,n} with
i≠j and the set of all nontrivial circuits
γ in
Γ(
A)—the associated directed digraph of
A, respectively. Subsequently, relations between these two results are investigated. Theoretic analysis and numerical examples show that these estimates are more precise than recent corresponding results in some cases.