A balanced survey is automatically created in real time, that is, while potential survey participants are evaluated. A survey histogram is automatically re-balanced with each new entry accepted as a respondent. An individual fills out a questionnaire providing demographic and socio-economic data. A vector representation of that person, referred to as an entry, is created. A similarity value is calculated indicating the similarity between the vector representation and a histogram vector representing the make-up of the survey. The similarity value is calculated by taking a dot product of the entry vector representation and the histogram vector. The system then determines whether the similarity value is greater than a similarity threshold value. If the similarity value exceeds the threshold value, the entry vector is integrated into the histogram vector, that is, the individual becomes part of the survey group.