To take an example from library science and use (or abuse) the theory behind the Functional Requirements for Bibliographical Records - a conceptual entity-relationship model that seeks to describe relationships between products of intellectual or artistic endeavor and their creators - we would like to elaborate on what constitutes a "restaurant." Library scientists will forgive us for intertwingling concepts from Groups 1, 2, and 3 of FRBR theory to forward our own pathetic ideas about restaurant identity, and those with more knowledge of the business will certainly find no difficulty pointing out the holes in our argument, for which we throw ourselves upon their mercy.
Four entities provide the foundation of FRBR: a Work, “a distinct intellectual or artistic creation"; an Expression, “the specific intellectual or artistic form that a work takes each time it is ‘realized.’”; a Manifestation, “the physical embodiment of an expression of a work"; and an Item, “a single exemplar of a manifestation."
Were we to apply this to the restaurant world, an example might look like:
Work: Food Fight restaurant
Expression: Southwestern-themed restaurants under the influence/auspices of Kevin Tubb
Manifestation: Tex Tubbs Taco Palace
Item: Tex Tubbs Taco Palace at 2701 W. University Ave.
Eating in Madison A to Z uses the Isthmus' Eats list at the Manifestation level. It is what allows us to visit only one location of a chain restaurant.
The FRBR model also helps us identify what changes cause a restaurant to be closed. Four facets make up a restaurant's identity: name, ownership, location, and theme (where theme entails a somewhat subjective appraisal of a venue's menu, service model, or style). We can elucidate our method with some examples of these factors changing and the effect this has on our project.
New name and ownership, same theme: we consider it closed and renamed, and revisit. This is the case in the India Darbar/Spice and Curry example. See also Cuppa Jo/Crema Cafe and American Family Table/Northside Family Restaurant.
New name, same theme and ownership: we consider it renamed and revisit, e.g. Ken's Cafeteria/Hunky Dory or Nifty 50's/Maid Rite (BAZ - Before A to Z), or sister restaurants such as Mi Cocina/Laredo's, Atlantis/Plaka, Copper Top/Bavaria. An exception is if the renaming does not change the venue's position on the List, as was the case with the East Side Business Men's Association/East Side Club.
New name and theme, same ownership: we consider it closed and revisit. Consider Cleveland's/Plaka, Bavaria Family Restaurant/Sofra Family Bistro, or Firefly/Tex Tubbs.
New theme, same name and ownership: we don't return. Had we made it to Restaurant Magnus before the switch from South American to Scandinavian fare, we would not revisit or rewrite our review [post! gah.]. This is mostly because we lack inside information into the vagaries of the Madison restaurant scene.
New ownership, same name and theme: we don't consider it closed, and don't revisit. Cafe Zoma was bought by Espresso Royale but continues to be a coffee shop called Cafe Zoma. Mad Dog's changed owners and some parts of its menu after we visited, but is still essentially a hot dog stand.
New ownership and theme, same name: we consider it renamed and don't revisit. To the best of our knowledge this has only happened in the case of Donut Delight. We assume Donut Delight began as a donut and coffee shop and kept its name when it changed owners; the new owners added Mediterranean fare to the theme, but we would not have revisited until the name became Mediterranean Delight.
New location, same ownership, name, and theme: we consider it a simple move, and do not revisit, as with Cafe Porta Alba.
One exception to all this was that early on, we were unaware that Angelo's in Monona and McFarland shared ownership, so we went to both locations. We do our best, but if you have other ownership information that affects our rules, please share!
Update: clarification of the unpublished codicle "What is a new name?" five-letter rule.