The “?” wildcard character is used both to match any single character in a pattern and as a place-holder for the cross-section identifier in pool objects.

EViews resolves this ambiguity by not allowing the wildcard interpretation of “?” in any expression involving a pool object or entered into a pool dialog. “?” is used exclusively as a cross-section identifier. For example, suppose that you have the pool object POOL1. Then, the expression,

is a regression of the pool variable Y? on the pool variable X?, and,

deletes all of the series in the pool series X?. There is no ambiguity in the interpretation of these expressions since they both involve POOL1.

Similarly, when used apart from a pool object, the “?” is interpreted as a wildcard character. Thus,

unambiguously deletes all of the series matching “X?”.