each node expects an input each cycle so you need to send the data to the node on the right before the jump

Change the ordering so that each node always does a MOV ACC RIGHT (it won't erase ACC when you do that) so that you can feed the comparison along and get them executing properly simultaneously (Yes, it's a bit of a wasted effort as two of the three comparisons will fail, but it is what it is).

So basically go like

START: MOV LEFT ACC
MOV ACC RIGHT
JGZ / JEZ / JLZ YES

etc etc etc.

(I suggest "YES" instead of "POSITIVE" just to avoid misinterpretation since positive can mean a + integer instead of saying 'that's correct')

PS. You can save yourself a line of code by omitting JMP START in the final lines of your nodes. The TIS-100 will automatically loop back to the start line of each node once it hits the last line of code for a given node.

Also if all you're doing is moving a 0 or a 1 down, forget the MOV 1 ACC / MOV ACC DOWN combos because the first line of the three nodes overwrites ACC anyway by fetching from the left as you pass that value along.