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Can you use your "free will"? Try your hand

people.ischool.berkeley.edu

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Re: Can you use your "free will"? Try your hand

#41

Post by qaq »

miika wrote: post #22

The question is never if we have free will or not. The question is if we are in a state where free will is available or not. For example, when I’m aware that there is space around myself, then I’m also aware that there are thoughts, feeling in the body, breath etc. In this state, I believe, it’s possible to choose. In this test I can choose the only press the other key and this algorithm doesn’t do so well. Then some…

Well you either do something because you are forced to or because you want to. You don't control either.

Re: Can you use your "free will"? Try your hand

#45

Post by boothby »

Examining the code, my first thought was to throw it a de Bruijn sequence[1]: a cyclic sequence of length 2^n that contains every string of length n as a subsequence. It should (and does) learn a length-32 de Bruijn sequence after only a couple of repeats, but performs miserably on a length-64 sequence.

With a little (computer-)elbow grease, one can find a sequence with perfectly free will. After a short time, it starts repeating every... that's right, 64 characters. So of course, we want to find the shortest possible prefix.

  ddddddfdddddffddddfffdddfdfdddff
  ffddfddfdffddffdfddfffffdfdfdfff
  dffdffffffffdffffffdffffddffffff
  dfdfffdffdffffddfffdfdfffdddffff
  ffdffdffffddfdffddffdfddfffdfdfd
  fffdddffdffdfddffddfdffddddfffff
  fdffffddfffdfdfdfffdddfdfdddffdf
  fdfddfddffddfdffddddfdfdfdddfddf
  dddddffffffdffffddfffdfdfffdddff
  dffdfddffddfdffddddfdfdfdddfddfd
  etc.
Note that the last two lines are a de Bruijn sequence. Repeat those until you get bored. That's how you exercise your free will.

There is a deterministic bias: when in doubt, the page guesses "f". If it flipped a coin instead, a few experiments show that the greedy algorithm I and omoikane use cannot beat 25% for long.

[1] https://en.wikipedia.org/wiki/De_Bruijn_sequence

Re: Can you use your "free will"? Try your hand

#47

Post by boothby »

omoikane wrote: post #13

The prediction algorithm is actually very straightforward[1]. It's a fun exercise to write a sequence generator specifically to defeat it. Here is a sequence that can get the prediction rate down to 13%: ddddd dfddd dffdd dfdfd ddfff ddfdd fdffd dffdf ddfff fdfdf dfffd ffdff fffff dffff ffddf fffdf dfffd ffdff ffffd ddfff Generated using this Perl script: my %table = (); my $s = "fffff"; for(my $i = 0; $i $table{$s}{…

You can improve that by around 13% if you soften the inequality (your > should be >=, I believe)

   table = {}
   s = 'ddddd'
   for i in range(100):
       if i%5 == 0:
           print(s)
       state = table.setdefault(s, {'f':0, 'd':0})
       s = s[1:] + ('f' if state['f']  0 else 'd')
       state[s[-1]] += 1

Re: Can you use your "free will"? Try your hand

#49

Post by simonh »

raincole wrote: post #19

I fail to see how it's related to free will. I can look at the digits of PI and press d and f depending it's odd or even. So what does it prove? Nothing. Being able to beat this algorithm doesn't mean that I have free will, and choose to fall into patterns (knowing the PI solution exists) doesn't mean I don't.

If the sequence is from an external source or reference, then the individual key presses are not a result of your free choices.

Re: Can you use your "free will"? Try your hand

#50

Post by erhaetherth »

simonh wrote: post #49
raincole wrote: post #19

I fail to see how it's related to free will. I can look at the digits of PI and press d and f depending it's odd or even. So what does it prove? Nothing. Being able to beat this algorithm doesn't mean that I have free will, and choose to fall into patterns (knowing the PI solution exists) doesn't mean I don't.

If the sequence is from an external source or reference, then the individual key presses are not a result of your free choices.

He's free to copy who/whatever he pleases.
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