Perhaps I should attempt an explanation here as it just occurred me that a link might be offputting for some.
Essentially, Mass Equivalence Interaction is based on the premise that if a particle is able to interact, it's present state must be the product of it's past interactions. It is then determined what changes must occur in a particle for it to become it's counterpart (neutral or charged) and attempts to derive the simplest and most logical interaction (action and reaction) that could produce such a transformation.
After determining the fundamental Mass Equivalence Interaction that would transform a proton into a neutron [specifically 2M + N = (5m÷2) + 1/2 N], I began to apply the concept to more complex events where I've noticed a number of interesting correlations such as the same small mass equivalence interaction that transforms a proton into a neutron is also (at least for those I've analyzed) the process known as isotope decay. The website just gives the concepts, math and various interpretations.