A Rubah Dlesah Lkaman is when we bring statistical proof as to which side is correct, even though the elements of statistics are not in fronr of us (such as 9 stores Kosher and one Traif, which would be a Rubah DEsia LKaman).
A classic example is the Gemorah in Bava Basra 93a, where the gemorah states that if one has a Camel which is at its time to have children, it is Muchzak to damage other animals, and is more statisticly likely to damage than other animals, and therefore if another camel is damaged by an unknown camel, we assume the camel which is at its time to have children is the damager. This is true even if we do not go after the majority (rov) by monetary cases, statistical proof is better than the simple “majority of cases”.
Please feel free to add or correct, it has been a while since I went through the topic.