arcgis desktop - Comparing two Digital Elevation Models (DEMs) from LAS files?

I have two LiDAR files (.las), one is original let's say with X points. And the other is copy of the first .las file but with Y points, where Y is less than X.

Now, I want to compare the Digital Elevation Models (DEMs) of these two .las files and visualize how different they are.

I want to get information like RMSE, standard deviation, among other types of comparison.

I would appreciate, if anyone could tell me what softwares, and ways to get the comparison info.