In this work we examine the ease of finding simultaneously two charges or two spins in various AO positions of a linear neutral polyene such as octatetraene. By applying the general multi-electron population analysis on a correlated wave function we calculate contributions from various ionic and covalent (in a probabilistic sense) resonance structures as well as electron-pair distributions with parallel and anti-parallel spins; the initial wave function used is a PPP + (quasi-total) CI wave function. Based on the second and fourth order anticommutation relations (and independently of the level of the MO wave function used) we show existing relationships between the quantities considered, as well as their constant behaviour. Covalent structures depend strongly on the parity and distance between the AO positions, while ionic ones arequasi-constant along the polyene. It is also shown that when the AO positions considered are non-vicinal, (+) and (−) charges appearmutually independent and the π-electron conjugation has, rather surprisingly, no effect on them.