Yesterday Tania wrote about some of the methods we use to ensure the accuracy of our data, including extensive training for interviewers, auditing a sample of questionnaires by going back to households and re-surveying them, and moving towards the use of electronic devices.

Another method is the use of visual aids. However these are also not without their problems, as this helpful example from Hyperbole and a Half demonstrates; 

You've probably seen some version of that chart before.  You may also have noticed how inadequate it is at helping you. Based on the faces, this is my interpretation of the chart:

0:  Haha!  I'm not wearing any pants!

2:  Awesome!  Someone just offered me a free hot dog!

4:  Huh.  I never knew that about giraffes.

6:  I'm sorry about your cat, but can we talk about something else now?  I'm bored. 

8:  The ice cream I bought barely has any cookie dough chunks in it.  This is not what I expected and I am disappointed.

10:  You hurt my feelings and now I'm crying!