Random Number Generator | Follow the Rules!

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Make sure it is really random. No cheating!
 
on Phys.org
You can't cheat, but you also can't "choose"; lose, lose situation
 
Before I vote, I would like to clear up one thing. Is 18 a random number?
 
jimmysnyder said:
Before I vote, I would like to clear up one thing. Is 18 a random number?

18 is as random as 7
 
I am going to bet that you will find a non-random distribution. There will be a statistically significant lack of hits at the ends as well as at the middle, resulting in a double-humped graph.

When asked to choose a number between 1 and 10, a more-than-average number of people will choose 3 or 7 because, psychologically, those numbers are more "hidden".
 
DaveC426913 said:
I am going to bet that you will find a non-random distribution. There will be a statistically significant lack of hits at the ends as well as at the middle, resulting in a double-humped graph.

When asked to choose a number between 1 and 10, a more-than-average number of people will choose 3 or 7 because, psychologically, those numbers are more "hidden".
I remember hearing that you can tell the difference between a sequence of 1's and 0's generated by a pseudo-random generator, and one generated by a person. Apparently, when people generate a sequence, they avoid long runs.
 
DaveC426913 said:
I am going to bet that you will find a non-random distribution. There will be a statistically significant lack of hits at the ends as well as at the middle, resulting in a double-humped graph.

When asked to choose a number between 1 and 10, a more-than-average number of people will choose 3 or 7 because, psychologically, those numbers are more "hidden".

I would have guessed the same thing -- but it seems that we have just the opposite in the distribution so far.

Of course, not so much as to make it fail a chi-square: 14.67 vs. the 19.68 needed to reject at 0.05 level with 11 degrees of freedom.
 
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I closed my eyes moved the cursor around in the vicinity of the numbers and then clicked. It took a couple tries.
 
Moonbear said:
Can you really "choose" a random number?

I closed my eyes and moved my cursor to one of the numbers (it was 7). Initially, I wanted to choose 4.I thought people wouldn't pick numbers near boundary because they appear less random but I guess I am wrong. (I went towards to middle to make it look like random)
 
TheStatutoryApe said:
I closed my eyes moved the cursor around in the vicinity of the numbers and then clicked. It took a couple tries.

I also did the same thing :)
 
DaveC426913 said:
I am going to bet that you will find a non-random distribution. There will be a statistically significant lack of hits at the ends as well as at the middle, resulting in a double-humped graph.

When asked to choose a number between 1 and 10, a more-than-average number of people will choose 3 or 7 because, psychologically, those numbers are more "hidden".

I would predict that if you put this poll up on any other forum aside from PF, that is precisely what you would see. I think that the folks here at PF are too aware of these patterns and will actually try to break them. I'm curious to see what pattern might instead emerge...maybe the mirror image of what you were predicting.
 
Moonbear said:
I would predict that if you put this poll up on any other forum aside from PF, that is precisely what you would see. I think that the folks here at PF are too aware of these patterns and will actually try to break them.
Guilty. :biggrin: I chose 1.
 
I used the random number scale on my Schmendrolog slide rule. This is a great military slide rule, as it's resistant to EMP.

The Amazing Schmendrolog...

This Polish slide rule (manufactured circa 1973) featured such groundbreaking slide rule innovations as the 'RND' scale (random number generator) and the famous blank area on the back for writing intermediate values and phone numbers.

In fact, this rule was the first to feature reverse polish notation, an important step in modern computing technology.

195-scales2.jpg


194-schmend.jpg
 
TheStatutoryApe said:
I closed my eyes moved the cursor around in the vicinity of the numbers and then clicked. It took a couple tries.
I did the same thing and ended up clicking on the advertisements. :shy:
 
I'm the first to pick 10. I'm awesome!
 
I want to choose 7 could I:biggrin:, now randomly picking I get 6 [apparently the first to pick it]


can I ask, what's the point of this thread?
 
drizzle said:
can I ask, what's the point of this thread?

Well I don't know what the OP's intent was, but for me, it's just pure, pointless, geeky entertainment :smile:.
 
No point IMHO.

No idea what should I vote for. I like 7 as well, but - as I like it - it is not random.
 
Borek said:
No point IMHO.

No idea what should I vote for. I like 7 as well, but - as I like it - it is not random.



just took the words out of my mouth...







hey I've just say so even before you do:-p.
 
lisab said:
Well I don't know what the OP's intent was, but for me, it's just pure, pointless, geeky entertainment :smile:.


really...




I don't know why the hell I feel stupid now!
:smile:
 
Moonbear said:
I would predict that if you put this poll up on any other forum aside from PF, that is precisely what you would see. I think that the folks here at PF are too aware of these patterns and will actually try to break them. I'm curious to see what pattern might instead emerge...maybe the mirror image of what you were predicting.

Haha exactly! I made sure to not choose 3 or 7.
 
The computer time is (was) 5:40 = 1740 hours. Added digits until they fall into the 1-20 range: 1+7+4 = 12. I'm amazed to see a (more or less) uniform distribution.
 
I was expecting 7 and 13 to pop out. Lucky and unlucky.
 
Also, were just over n=30, so now we're stastically significant.
 
Let's compare to a pseudorandom number generator...
Code:
 1 : 4   0
 2 : 1   1
 3 : 0   2
 4 : 3   1
 5 : 2   3
 6 : 3   3
 7 : 7   5
 8 : 1   3
 9 : 1   5
10 : 2   0
11 : 1   2
12 : 1   2
13 : 2   2
14 : 1   4
15 : 1   2
16 : 2   1
17 : 3   1
18 : 4   2
19 : 1   1
20 : 2   2

Here's the code I used...

Code:
#include <iostream>
#include <cstdlib>

   using namespace std;

    int main()
   {
      const int N = 42;
   
      int freq[20] = {0};
      
      srand(time(0));
   	
      for(int i = 0; i < N; i++)
      {
         freq[ rand() % 20 ] ++;
      }
   
      for(int i = 0; i < 20; i++)
      {
         cout << (i+1) << " : " << freq[i] << endl;
      }
   
      return 0;
   }

Ironically, the human one seems to be more "random" than the pseudorandom one.
This leads me to think that people are cheating.
 
According to your program, 7 is lucky!