Subject-verb agreement is an example of signifier redundancy in natural language. Additionally, the human senses are highly tuned to noticing exceptions to the simple and expected, such as a shooting star in the night sky or the odd noise in the engine. TowerView takes advantage of this tendency in order to let users instantly notice critical ranges in a few variables out of thousands. This feature has been used to rapidly pull patients in danger during large clinical trials and by NASA to instantly find a failing satellite component among the thousands in orbit. Colors differentiate education ranges, with violet the highest and yellow the lowest.
Men are on the left half, women on the right, with seven age ranges for each sex.
The center of the bars indicates salary levels with the distance between the top and bottom of a bar the standard deviation. Of course people can perceive many dimensions of information instantly in even the slightest variations of, say, facial expression and body form. Considering how sensitive our visual sense is, the best products now available tap only a small fraction of the power of visual presentation. But there I go, thinking in pictures again. Further Studies in the Psychology of Pictorial Representation , Cornell University Press, 1982.