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September 2016

Date: 2013-07-25 12:43
Security: Public
Mood:curious curious
Subject: An experiment about PINs

I want to try an experiment.

Imagine you're calling an automated phone system to set up an account. The phone system asks you to make up your own PIN code to control access to the account, and to press the # key when done.

Did you think of a number? Good. Hold that in your head. I'm not going to ask you for it, but I do want to ask you a few questions about the number you chose under the cut, as an anonymous poll. (Meaning that even I can't see who answered what, for security.) If you haven't thought of the PIN code you would use in this hypothetical situation, do so now.

I explain why I'm doing this in another cut inside the cut below!

And here are the questions:

Poll #13945 PIN questions
This poll is anonymous.
Open to: Registered Users, detailed results viewable to: Just the Poll Creator, participants: 43

How many digits did your chosen PIN have? (Choose 10 if your number has more than 10 digits.)

Mean: 4.47 Median: 4 Std. Dev 1.25
10 (0.0%)
20 (0.0%)
30 (0.0%)
435 (81.4%)
54 (9.3%)
61 (2.3%)
70 (0.0%)
82 (4.7%)
90 (0.0%)
101 (2.3%)

Discard the last 2 digits of your chosen PIN (for example, 384 -> 3, and 48932 -> 489). What number are you left with? (Remember, nobody, not even me, can see your answer.)

Mean: 25.72 Median: 29 Std. Dev 6.00
or below 91 (2.3%)
101 (2.3%)
110 (0.0%)
121 (2.3%)
131 (2.3%)
140 (0.0%)
151 (2.3%)
160 (0.0%)
171 (2.3%)
180 (0.0%)
192 (4.7%)
201 (2.3%)
211 (2.3%)
220 (0.0%)
230 (0.0%)
240 (0.0%)
250 (0.0%)
262 (4.7%)
270 (0.0%)
280 (0.0%)
or above 2931 (72.1%)

The reason I'm asking this is because I strongly suspect that almost everybody, when they think of a PIN code, will think of one which is 4 digits long - because most things will ask for a 4-digit PIN. Notice that I never stipulated above that it had to be 4 digits! In fact, I explicitly made clear that the phone system would ask you to use the # key to finish your number, meaning that it's not assuming anything.

Further, I also suspect that a lot of people will think of a year, that the majority of those people will pick a year above 1000, and that the majority of *those* will pick a year within their lifetime, which would put their answer to the second question as 19 or 20. I'm curious to see if the data supports my thoughts, and to what extent!

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