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\begin{abstract} An $(X,Y)$-descent in a permutation is a pair of adjacent elements
such that the first element is from $X$, the second element is from
$Y$, and the first element is greater than the second one. An
$(X,Y)$-adjacency in a permutation is a pair of adjacent elements
such that the first one is from $X$ and the second one is from $Y$.
An $(X,Y)$-place-value pair in a permutation is an element $y$ in
position $x$, such that $y$ is in $Y$ and $x$ is in $X$. It turns
out, that for certain choices of $X$ and $Y$ some of the three
statistics above become equidistributed. Moreover, it is easy to
derive the distribution formula for $(X,Y)$-place-value pairs thus
providing distribution for other statistics under consideration too.
This generalizes some results in the literature. As a result of our
considerations, we get combinatorial proofs of several remarkable
identities. We also conjecture existence of a bijection between two
objects in question preserving a certain statistic. \end{abstract}
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