1. A method for creating a data-driven attribution model, comprising: accessing a database to identify, for a given time period, a plurality of visits to a particular website, each of the plurality of visits associated with a visitor identifier; identifying, for each visitor identifier, a first plurality of paths associated with the visitor identifier from the plurality of visits to the particular website, each path including at least one event, each of the at least one event: associated with an index position indicating a position of the event within the path; and having an event type from among a plurality of event types; deriving, by a processor, for each of the first plurality of paths, one or more subpaths from the path, each subpath comprising a subset of the events of the path; determining, by the processor, a second plurality of paths including the first plurality of paths and the subpaths derived from the first plurality of paths; defining a plurality of path types, each path type defined as a path comprising a number of events, the events comprising a series of event types occurring in a particular order at particular index positions within the path; determining, for each of the second plurality of paths, a path type from the plurality of path types by identifying the path type having the same number of events as the path and series of events types in the order and the index positions as the path; determining, by the processor, for each path type, a path-type conversion probability by calculating a ratio of a number of paths of the path type that led to conversions to a total number of paths of the path type; calculating, by the processor, for each of the plurality of the path types associated with the identified paths, a counterfactual gain for each event based on: a first path-type conversion probability of the given path type; and a second path-type conversion probability of a second path type, wherein the second path type is identical to the path type except that the second path type does not include the event for which the counterfactual gain is calculated; determining, by the processor, for each event of each of the plurality of path types, an attribution credit based on the calculated counterfactual gain of the event; and storing, for each of a plurality of the path types associated with the identified paths, the determined attribution credit for each event included in the path type.