A large passenger transport organization in Britain issued a poster rejoicing over the reliability of its services The poster compared the number of occasions when passengers reached their destinations in accordance with the timetable with the number of delayed arrivals. “The red dots ran late,” said the headline. “The black dots ran on time.” And the message seemed clear enough. Black dots so greatly outnumbered the red ones that they appeared to occupy almost the whole of the advertisement space. The counts of black and red dots were indeed proportional to the numbers of journeys completed on and off schedule. But the designer had squeezed the red dots closer together, down one side of the poster, so that they covered a disproportionately small area compared with the black dots. The actual record of unpunctuality was far worse than the impression gained at a glance.
This is just one example of ...
