I have a Dell Inspiron 15 (3558). Ever since I upgraded to Ubuntu, there have been problems where the touch-pad randomly jumps when using it. For example I could be scrolling up and the cursor would instantly jump to the top at the slightest touch. I lowered sensitivity in settings but that doesn't seem to help. I read a solution online where the touch-pad sensitivity seems to be fixed but the tap-and-click function doesn't work. I don't want to sacrifice the tap-click function for sensitivity. Here are the results of xinput:
I observe the behavior persists only when my laptop is plugged in. Found that one when I was looking through this link.
One temporary hack is by placing your hand on the keyboard or any metal part of your laptop to ground it.