Random Magic Paths - is it truly random?

[Saber Cherry]

Furthermore, unless I'm just up too late and should really go to bed now (probably true), it seems that the chances of 20 random picks missing a least one path (in other words, getting 20 consecutive sages and still not having 8 paths between them) is 43.6%, which is relatively high. Math:

1-((1-.0692)^8), where the .0692 is derived from the same calculation as above.

As far as RNGs go, I found a really nice one, called the Mersenne Twister. It is a software RNG, but the software actually finds stray radioactive particles in the dust on your CPU and monitors them for randomness. If you clean your case a lot the randomness goes down, which may explain some of the problems in this thread.

On the other hand... I just disassembled dom2.exe and got this little code fragment... maybe this is the problem?

Code:

---

public int rand(){

	for(int i=0; i<100; i++){

		if(seemsRandom(i)){return i;}

	}

	return secret_very_random_number;

}



public boolean seemsRandom(int x){

	// note:  add some stuff here before Dominions 3 is released

	return true;

}



private int secret_very_random_number=42;

---

[The_Tauren13]

roflmfao

[BigDaddy]

Arallen and Bummer_Duck, if you are actually seeing long strings of alternating air and earth mages, I would suggest that it is a bug, but with the sophistication of random number tables and RNG these days, I believe the flaw would be in the windows OS. If you're using a different OS, I almost can't comprehend the problem. Depending on the actual coding of course, it could be caused by an artifact in the memory of the computer, caused by windows clunky and inefficient memory management.

Reboot, and try again! But be warned random systems do do unexpected things, and thats the beauty of them.

[BigDaddy]

Restarting the computer incessently is a dogmatic method of course, if you're not seeing a real pattern.

If the system wasn't random you could use and expert system (thats the engineers term for artificial intelligence) to predict the outcome. Of course with the turing machine's (a computer is a turing machine)inability to actually produce random numbers, with enough samples the expert system may eventually learn how predict the supposed randomness, but it would take quite a few samples and a very sophisticated expert system.

Has anyone learned anything from reading these posts?

(Corrected spelling)

[Kristoffer O]

I learned that Bone Daddy is a nerd

[BigDaddy]

Thats funny because i'm not bone daddy and Ivan's posts where nerdier. No offense intended Ivan.

[Ivan Pedroso]

BigDaddy said:
Thats funny because i'm not bone daddy and Ivan's posts where nerdier. No offense intended Ivan.

Hehehe none taken

"20 sages in a row with exactly 1 path missing":
(7/8)^20 *8 = 0.554

Explanation:
the (7/8) is the chance of getting one of the 7 "good" paths when you hire a sage.
^20 is just 20 such sages in a row.
*8 stems from the fact that you can choose your pool of 7 "good" paths from the 8 possible paths in 8 different ways.

General formula:
(chance of one good)^(number in a row) * (ways to make a good pool)

Getting 20 in a row with exactly 2 paths missing:
(6/8)^20 * 28 = 0.0888
(28=(8!)/(6!2!) is the number of ways of taking 6 from a sample of 8)

Getting 20 in a row with 1 or more paths missing:
~65%

Surprisingly high ? or ?

[Turms]

You reasoning is invalid BigDaddy. Johan Osterman already posted that Dominions II uses a pregenerated random number table. That means it's random number generator works exactly the same in any computer with any OS. If it didn't the battle replays wouldn't work.

I have still a question though:
How is the seed for a new turn generation chosen?
The normal way is to take it from the clock or something. That is the only place I could think that could somehow affect the randomness of picks (very unlikely).

Turms

[BigDaddy]

OK, I didn't notice Johan's post (I was wondering what method was used). Pre-generated number tables are very common (they are more efficient), but I think an artifact could still cause problems.

I don't think the seeding technique is likely to be the problem. I believe the seeds are used to select a starting point on the table and a "movement" pattern around the table, and it can be made even more comples. Repeats are highly unlikely in any case.

[Kristoffer O]

BigDaddy: But it was Bone Daddy that claimed that we and he and his whole family were nerds

Turms: Clock I believe.