  This paper proposes a simple procedure to decide whether the
empirically-observed adjacency or weights matrix, which characterizes the graph
underlying a socio-economic network, is sufficiently symmetric (respectively,
asymmetric) to justify an undirected (respectively, directed) network analysis.
We introduce a new index that satisfies two main properties. First, it can be
applied to both binary or weighted graphs. Second, once suitably standardized,
it distributes as a standard normal over all possible adjacency/weights
matrices. To test the index in practice, we present an application that employs
a set of well-known empirically-observed social and economic networks.
