central facility 16 determines at a block 40 whether the central facility 16 has received information in response to the application downloaded at the block 38 if the server of the central facility 16 has not received the information the server determines at a block 42 whether it should again send the application down to the user 39 s computer if the application can be resent the processing at the blocks 38 and 40 is repeated in this manner a predetermined number of attempts may be made to retrieve history data from each panelist if the application should not be resent program flow returns to the block 32 to await another message if the server at the central facility 16 has received the history information as determined at the block 40 the server at a block 44 suitably processes the history information and then logs the history information in a database along with history information received from other panelists the history information can be assembled into reports as directed by the customers of the central facility 16 in processing the history information the server at the central facility 16 preferably arranges the history information from different browsers into a common format for example because some browsers may contain duplicate data and some may not it may be preferable to eliminate duplicate data it should be noted that some or all of the processing required to transform the data to a common format may be effected on the panelist 39 s computer also the data from all weeks and days should be merged and any entry that is a duplicate may be discarded in favor of the most recent entry the parameter that controls the length of time that the history information is maintained is an integral part.