The invention relates to a computer based method and system for automatically determining in a document an object satisfaction score (44), choosing at least one of either a positive score or a negative score, comprising the steps of: subdividing the document into windows of words; selecting one of said windows when it contains at least one descriptive property corresponding to a key subject of said object and/or when it does not contain any descriptive property corresponding to an anti-key subject of said object; processing each selected window to determine a positive or negative score of said window by counting the occurrences of positive and negative concepts; and cumulating the scores of the selected windows to obtain said object satisfaction score for the document.