How can we measure the quality of a pseudo-random number generator?
Let's say I came up with a method of generating random numbers. I do so in such a way that the sequence of random numbers does not repeat and that statistically in the long run all numbers will appear with equal frequency. Does that make my randomness generator truly random? I think not, because there might still be more complicated patterns allowing a being of higher IQ to predict the next numbers deterministically. After all the algorithm itself remains deterministic. So how can I know how close to actual randomness I am?
>with equal frequency only if the underlying distribution being modeled is uniform
Caleb Bailey
Uniform distribution is the only distribution we need to generate. Every other distribution can be simulated from there.
Tyler Rivera
Regardless of how good your algorithm is all I have to do is guess your input, which will always be ctime. Then what I actually have to guess is what operations you do on the input and like that, we are done.
Lets say that X is the output of ctime at the current time and that your algorithm is
N = (X*3)%10
Which will obviously return a random number from 0 to 9.
Then if I know that multiplying X by 3 is your only computation then all I need to do is get my calculator and calculate
N = ((X+60000)*3) % 10
And now I can predict the result of your RNG 1 minute into the future with 100% accuracy, every single time.
It is a sad reality we live in, randomness does not exist.
Charles Garcia
define random
the sequence 1111111111111 is random
it contains information but it's random
Caleb Murphy
F*ck you're racist photo in the op
Caleb Richardson
It is not racist. It is not mocking muslims, it is mocking regressive liberals.
The point it is trying to make is that regressives nowadays think that muslims, who have been raised in a society under Sharia law for all their life (so it isn't really entirely their fault), can simply unlearn their inherent sexism (for example) by simply telling them "Hey, don't rape those girls there, pretty please."
It is because of this foolish belief that european women are getting raped by the hundreds and Sweden, the most regressive country, is now the rape capital of the first world.
Evan Rogers
It's not racist. The terrorist's race isn't shown, and anyway he turns out to be a nice guy.
Ethan Murphy
it's racist because it doesn't show the beggining of the story where devilish white men came and raped his sisters, bombed his children, and burned his country to the ground
notice how there is no white male in that pic, only "stupid white women" and "evil muslims"
Nolan Jones
It's an ideal utopia world, like 50 years in the future, where white men don't exist anymore.
Kayden Lewis
Countries have been at war since the beginning of time, and there were long periods were the "muslim world" was winning by a long shot.
Hate the game, not the player.
Gabriel Morales
What if the input is drawn from the neutron flux of a nuclear reactor? Or some form of unpredictable input
Joseph Watson
Through some mathematical model you could predict the conditions and then you could predict the output of the algorithm.
Here even 1% accuracy would be amazing and I'm sure it would be possible to predict it to much higher accuracy.
James Peterson
If you came up with a brand new method for generating pseudo-random numbers, one way to test if your RNG respects the uniform distribution is making a statistical hypothesis test. Assume that the distribution of your random variable is uniform and take a sample of at least one million of random numbers and check if you have enough evidence to reject you hypothesis. If not, simulate more and more numbers until you see at which point your RNG begins to be predictable or does not corresponds to a uniform distribution. Chi-squared test is one method that you can use. I don't know any other method right now.
William Allen
random implys no cause nothing is random things dont happen bc they want to
Isaac Jenkins
>It is a sad reality we live in, randomness does not exist. Wat. Clearly you are a computer scientist. Randomness is integral to reality via quantum mechanics. You could have hardware that samples some stochastic phenomenon, like thermal noise, if you want random.
Still, PRNGs are super useful because they let you reuse the same (pseudo) random number string, which can be important in simulation and debugging.
Isaiah Anderson
You can be racist against Muslims anyways
Angel Davis
>Let's say I came up with a method of generating random numbers. >the algorithm itself remains deterministic Why are you introducing the "algorithm" aspect so late in the question? If you're talking abut a computer program, then no, of course the sequence isn't truly random. That's a leading question, OP.
I'm just a code monkey, but even I know you'd need and actual random phenomenon for your random numbers. Are you one of those "no free will" fagots? I swear you're worse than the /x/ and /pol/ folk who come here. At least they're wrong in a blatant, obvious way.
Nathaniel Anderson
>There exists a mathematical model of an arbitrary random system Wat
Camden Lopez
>Random implies no cause Could you flesh out this argument? Genuinely curious
Wyatt Edwards
>It is not racist. It is not mocking muslims, it is mocking regressive liberals. >implying radical ak-47-and-black-hood style terrorists aren't typically politically conservative religious fundamentalists
>not racist. It is not mocking muslims, >implying "muslim" is a race
Jordan Hall
>Still, PRNGs are super useful because they let you reuse the same (pseudo) random number string, which can be important in simulation and debugging. As long as a PRNG is unpredictable in a practical sense, is there really a difference between it an a genuinely random series?
Cooper Jackson
Most Muslims are Arabs and most Arabs are Muslim. Because of this, the term is often used interchangeably, and you knew what he meant.
Landon Price
>, and you knew what he meant. Nope. I'm very doubtful about "most muslims are abars", and besides, I don't recognize arabs as a race either. Aren't they Caucasians?
Cameron Bailey
The comic is mocking the naivete of the people who want to bring Muslims over, not the Muslims themselves.
Oh, you're just being intentionally obtuse. Nevermind.
Tyler Gutierrez
There is nothing racist about hating a religion. I honestly believe Islam is not a religion of peace, for the majority of its believers.
That does not make me (or the guy you were replying to) racist.
Every single one could be the same race, and I still wouldn't be racist.
I hate their beliefs, and think they are fundamentally at odds with the western world.
James Diaz
The image is clearly mocking gun-free zones. I'll spell it out for you:
1. Man wants to kill people with a gun 2. Woman shows man that he is not allowed to use guns where he currently wants to, by pointing to a sign that says "no guns allowed" 3. Man obeys woman and becomes peace-loving apple picker
It is funny because obviously, people who are breaking the law don't abide by it, thus rendering "gun-free zones" ineffective against criminals. Criminals don't follow the law. Telling a criminal to not break the law doesn't make the criminal stop breaking the law. It's like everyone mysteriously forgot what a criminal was over the past 50 years. No one can possibly imagine someone NOT following the law!
Jaxson Anderson
Half of those posts weren't even discussing the picture, dipshit
Dylan Sullivan
>The image is clearly mocking gun-free zones. I'll spell it out for you: It can't be that clear, if you have to explain it.
>Most Muslims are Arabs Nope. You have no idea how widespread islam actually is.
Xavier Reed
>The image is clearly mocking gun-free zones. I'll spell it out for you:
What an amazingly insightful post. It even explains why the man with the rifle is clad in common MT garb and shouting "Allahu Akbar." It is to mock gun free zones, of course!
