In this case, the true structure would be O->E, O->W, I->E. If O is unobserved, then you confuse a fork for an arrow, but I’m not sure you can actually get an arrow pointing the wrong way just by omitting variables.
In this case, the true structure would be O->E, O->W, I->E. If O is unobserved, then you confuse a fork for an arrow, but I’m not sure you can actually get an arrow pointing the wrong way just by omitting variables.