1: The distribution center became more punctual after the new scheduling system was introduced. · 2: Applying the old on-time rule to shipments under the new system also yields a rate near 91 percent.
Quist and Rao agree on the numbers in the report but split on what those numbers mean. The columns ask you to pin the real point of disagreement and then to find the one fact that would resolve it.
The first selection, the disagreement. Both analysts accept that the recorded on-time rate rose nine points, and both accept that the new system changed how on-time is counted; Rao says so and Quist does not dispute it. What they actually divide on is whether the center became more punctual, that is, whether real performance improved or only the bookkeeping did. Quist says it got more punctual; Rao doubts it. That is the claim they disagree about, the first selection.
The second selection, the arbiter. The disagreement hangs on whether the nine-point rise reflects real improvement or just the looser counting rule. The fact that would settle it for Quist is this: apply the old on-time rule to the shipments handled under the new system and see whether the rate is still near 91 percent. If holding the counting rule fixed still shows a high on-time rate, then the gain is real performance, not a scoring change, and Quist is vindicated. That finding neutralizes Rao's whole objection by removing the measurement change as the explanation. That is the second selection.
Watch the two pulls. The recorded-rate statement, that the rate rose to 91 percent, looks like the disagreement, but it is the shared starting point: neither analyst disputes the recorded number, so it cannot be what they argue over. And the changed-counting-rule statement is the basis of Rao's doubt, also accepted by both, so it too is common ground rather than the disagreement. Picking either for the first selection mistakes agreed ground for the dispute. For the second selection, none of the remaining facts settles anything: that the new system cost more, or that other centers adopted similar systems, says nothing about whether this center actually improved once you control for the counting change.
The discipline: the disagreement in a dialogue is the claim the speakers take opposite positions on, not the data they share, and the finding that settles it is the one that controls for the very thing the doubter blamed.
Disagreement: whether the center became more punctual. Settles it for Quist: the old rule still yields about 91 percent.