For final exams, we use to mark across all sections of a course (so for 101 type courses, this can be hundreds to 1000s of papers). Get all the profs and TA's

For final exams, we use to mark across all sections of a course (so for 101 type courses, this can be hundreds to 1000s of papers). Get all the profs and TA's together, break in to groups taking one problem or set of problems. Then you random sample (each group takes a stack) to get a feel for the 'typical' errors, once that's done - you are a machine going through the stacks. Every once in a while (not that often) you run into a novel error or approach, and the group discusses.