On one hand, the Moon has lower gravity, and the gravity from Earth also reduces the distance the it has to span. This is particularly true for EML-1, and a little less so for EML-2. I don't know if there are any other coherent ideas of a lunar space elevator, so restricting the discussion to EML-1 would be best.
On the other hand, Mars has a rotation similar to Earth. Its day length is nearly 30 times the moon, so it seems like this would very heavily favor Mars.
Which one would have the lower requirement for material specific strength?
A similar question has been asked on Quora, but lacked any genuine empiricism.