1. A machine-implemented caller interface method, comprising: receiving a sequence of recognized characters beginning with a first recognized character and ending with a last recognized character; selecting successive characters one at a time from the recognized character sequence in order beginning with the first recognized character; for each selected character, constructing a current potential match set of potential character string matches by appending one or more characters selected from a set of misrecognized characters including the selected character to each potential character string match in a prior potential match set constructed for a preceding selected character, if any, and deleting from the current potential match set potential character string matches missing from a list of reference character strings; and transmitting for presentation to a caller a reference data item corresponding to the potential character string match in a current potential match set containing one a single potential character string match after non-matching potential character string matches have been deleted.