Probability, randomness and chance

It’s not strictly on topic, but I caught a fascinating discussion on probability, randomness and chance on Radio 4’s series The Infinite Monkey Cage.

Brian Cox

Co-presented by astrophysicist Professor Brian Cox, the discussion ranged from the ‘birthday paradox’ where the probability of two people in a random group of 23 chosen people sharing the same birthday is greater than 50%, to the idea that people are predisposed to pattern recognition because we have evolved with the survival mechanism to extract patterns from not much data ie. spotting tiger stripes in the surrounding foliage.

Mind you I’ve enjoyed what Professor Cox has to say ever since I accidentally watched Danny Boyle’s Sunshine with the scientific commentary dubbed on to the action and found that it all made sense (sort of).

But one of the questions raised by the programme was to ask why people interpret a chance event as being somehow preordained, and why we seek to interpret such results with other meanings. The thought was that because people have a memory of past events, we use that as a filter to understand present events.

It reminded me of how patterns and numbers crop up all the time in design and how designers can use this knowledge to engage their audience by having them infer content structure, through the filter of previously remembered events, from the groupings and alignments in the design.

Such relationships as the golden ratio of 1 to 1.618, the rule of grouping in threes and fives, picture composition using intersecting thirds, and all manner of gestalt relationships are used to help the viewer to process information more quickly.

A practical example of this effect can be seen in website design. Most peoples experiences of the web are made elsewhere, so your site needs to conform to the expected web page layout if you want the user to be able to quickly engage with the content.

Of course, knowing that rule means that, in the case of Johnson Banks, you can break it for good effect if you want to surprise your audience.