Usually I stick to the idea of 'basis' at the delivery points approved for settling futures contracts, because there the difference in basis is comparing apples to apples at a place that is supposed to be the standard. However, basis in other areas is also reflective of this, though there may be some regional variation over time.
I sell my grain based on cash, and my market does not have the basis game most other markets have. The closest there is to basis here is how SWW compares to SRW futures contracts (the usual meaning of basis out here the few times it comes up in a conversation). I'm more inclined to look at cash SRW at NO compared to Portland SWW. In any case, I'm oriented to cash. I could care less what CBOT futures do, and our market doesn't respond much to Chicago anyway except for very generally.
If I were selling SRW for export, I'd be looking at NO cash as a guide, or the export outlet that serviced my market. If the CBOT doesn't reflect that reality, why should I care? If a 'correction' in Chicago happens that affects my market that I think is counter to physical trends globally (assuming the 'correction' is down), why wouldn't I hold up any sale that might be pending in my plan and wait for Chicago to get it out of it's system? Whatever Chicago does in any given day, I believe that physical pulls futures back in line with reality. It may be a separate reality, but it's going to track.
Here, we might move 5¢ for every 20¢ in Chicago, or maybe not that. Maybe even go up.
