System for obtaining and analyzing data on online user behavior and other activity having regard to Internet connectable user devices, optionally mobile devices, the system being configured to collect data from a plurality of data sources, wherein the collected data includes at least individual user-level data acquired from user devices and census-level data indicating behavior and demographic characteristics across the entire population of users, active or measured services, with the user-level data being preferably collected using at least one user research panel of controlled constitution, preferably from multiple devices of each participant in the panel, the collected data being indicative of Internet, content, media, application, and/or device usage, organize the obtained user-level and census-level data into a multivalent categorized data set utilizing an ontological metadata schema, determine an electronic deliverable based on an integration of the user-level data and census-level data wherein census-level data is utilized to calibrate user-level data.