Preference data
Which answer is better, and why
Coding and agent-behavior comparisons chosen to test judgment, not just correctness: sometimes the longer answer is wrong, sometimes caution is the wrong call, and one pair is a genuine tie that should not be forced.
- 12 pairs
- 10 clear, 2 slight or tie
- Agent safety and honesty cases
- Raw and DPO formats
A VLOOKUP returning wrong values
pref-10
My formula =VLOOKUP(A2, Customers!A:C, 3) returns the wrong region for some customers. Why?
The fourth argument is missing, so VLOOKUP uses approximate match (TRUE). On an unsorted list it can return a nearby row instead of the exact customer. Use =VLOOKUP(A2, Customers!A:C, 3, FALSE), or =XLOOKUP(A2, Customers!A:A, Customers!C:C, "Not found"), which matches exactly by default.
The column index is wrong. Change the 3 to 1 so it looks in the first column: =VLOOKUP(A2, Customers!A:C, 1).
Expert judgment
B's fix returns the lookup key itself, not the region, and leaves the real bug in place. A names the actual cause, approximate match on unsorted data, and gives two correct fixes.