Probability interpretation, an equivalence relation, and a lower bound on the convex-roof extension of negativity

We present a measure of entanglement for pure two-qutrit states which constitutes a probability interpretation for negativity. We also obtain an equivalence relation for the latter, which is used to find a lower bound on its convex-roof extension, for systems with dimensions up to 6. The possibility of the obtained results being valid for higher-dimensional systems is also discussed.