associating a plurality of electronic devices with a plurality of viewers;

enriching electronic content device data for the plurality of electronic devices with consumer enrichment data, the electronic content device data identifying a plurality of purchasers;

setting a time window associated with a portion of each electronic content instance among a plurality of electronic content instances on which a message was presented based on a predetermined time window size, the time window size being greater than a duration of the message;

determining whether an individual viewer of the plurality of viewers viewed the electronic content instance for at least a threshold percentage of the time window;

upon determining that the individual viewer viewed the electronic content instance for at least the threshold percentage of the time window, identifying a single message exposure event for the individual viewer, wherein the message exposure event comprises a truncated time stamp for a time period that the message was presented and viewed by the individual viewer;

calculating, for each viewer of the plurality of viewers, message weight as a function of a number of exposures of the message as applied to the viewer based on the message exposure event;

calculating, for each viewer, a score representing a degree-of-targetedness between a target for the message and the viewer;

generating a multi-dimensional model of message effectiveness that models combined effects of the message weight and a degree of targetedness based on a combination of message weights and degrees of targetedness for the plurality of viewers; and

applying the multi-dimensional model to the electronic content device data and viewer activity data to track viewer activity attributable to the message.