THE VALUE OF NOT FOLLOWING INSTRUCTIONS

As Shane Frederick has noted, if you say “A bat and a ball cost $1.10. The bat costs $1 more than the ball. How much is the ball?”, you will notice that the vast majority of your friends will say “10 cents” instead of the correct “5 cents”, because they don’t pay attention to the “more than the ball” bit. They assume you mean that the bat costs a buck.

But Decision Science News would like to pause and say a few words in defense of not listening to exactly what is said. What if we took instructions literally? If we did, when we got emails from British Airways saying “Your British Airways flight is moving to Heathrow Terminal 3″ as their subject, we would actually believe that our recently booked British Airways flight (to Geneva) was moving to Heathrow Terminal 3. And we’d be wrong.

If we then went on to read that the change only affects flights to Barcelona, Nice, and three other cities where we are NOT going, we would be completely perplexed, thinking “How can my flight be moving and not moving at once? It’s impossible!” We’d panic. We’d call BA. But we don’t do any of that. We just shake our heads and think “Worst … subject line … ever”.

As Decision Science News reflects and tries to find cases in which it pays to be perfectly literal, it can’t. Even when dealing with computers, even when reading the output of statistical routines, one needs regularly to think “Ok, SAS (or R or STATA or SPSS) you say that, but we both know you don’t mean that.”