I guess you just said what I was saying in my reply to Kinze. I wasn't really picking up on that. What tools are required to compare a machine to another machine?

I'm sitting here looking at my map on EASi Suite. I zoomed in far enough that the visible portion of each pass represented 0.50 acres on a 12 ro head (not intential, that's just how it worked out). Then I took my "Draw a polygon query" tool and selected that pass for the length of the screen. What I found was the following information for 6 passes:

Pass 1: 0.5 acres - 208.00 bu/acre

Pass 2: 0.51 acres - 207.84 bu/acre and same direction as pass 1 so likely different combine

Pass 3: 0.51 acres - 205.88 bu/acre going same direction as pass 1 and 2 so likely all different combines

Pass 4: 0.51 acres - 201.96 bu/acre going opposite direction as pass 1-3

Pass 5: 0.50 acres - 210.00 bu/acre going opposite direction as passes 1-3 and same direction as 4

Pass 6: 0.50 acres - 222.00 bu/acre going opposite direction as passes 1-3 and same direction as 4 and 5

As I look back I can see that I started on the wrong pass. Looking at the pattern it's clear that there are 4 combines that were in this particular field but it gets me an idea. Things actually don't look horribly far off with respect to one another. However, how do I know which of those passes is which combine so that I can compare them to one another throughout the field to try and determine relative error? There is nothing about the data that shows which combine is which as far as I can tell. If I could figure that out it would help me a lot I think. Thanks.