1. A method comprising: identifying, in response to a query relating to at least one category, plural cases from a set of cases; receiving, by a system having a processor, indications corresponding to user confirmation or user disconfirmation of individual ones of the plural cases as belonging to the category, wherein user confirmation of a first of the plural cases as belonging to the category includes user selection of a first user-selectable element in a display screen, and wherein user disconfirmation of a second of the plural cases as belonging to the category includes user selection of a second user-selectable element in the display screen; in response to the indications corresponding to the user confirmation of the first case and the user disconfirmation of the second case, adding, by the system, the first case to a positive training set, and the second case to a negative training set; training, by the system, a categorizer based on the positive and negative training sets; computing, by the system, a quantification measure associated with cases in the category based on output from the trained categorizer, wherein each of at least some of the cases in the category has a data field, and wherein computing the quantification measure comprises computing an aggregate of the data fields of the at least some of the cases in the category; and adjusting, by the system, the quantification measure to calibrate for inaccuracy of the trained categorizer.