## The Shuffler Thread For a New Generation

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bubba0077
Joined Feb 2002
10619 Posts
I thought it was about time to create a new shuffler thread to throw out a lot of the chaff and consolidate all the 'important' information in the first post where people will hopefully see it.

First, the [O]fficial explaination of how the MTGO shuffler works, originally provided by Chris Green, president of Leaping Lizards (who developed the thing), preserved by muriban and passed on to Vitalogy1994 who posted it in the last incarnation of this thread:
ChrisG wrote:
MTGO's Shuffle Algorithm...get the technical low down... March 15, 2002 by Chris Green A technical description of Magic Online's shuffler and random number generator. The core random number generator used is "Algorithm A", from Knuth's "Art of Computer Programming", sec 3.2.2. This is a fast, easy to implement random number generator. Knuth states that it has "consistently produced reliable results, in extensive tests since its invention in 1958." I first implemented this generator in 6502 assembly code in 1981 or so, and it has never failed me. The implementation of this generator used in our libraries uses the standard constants (24,55). Because this is somewhat fewer than the number of bits required to produce all possible hands, it was augmented with another generator using the constants (33,68). This yields a total state size of 3936 bits. Both generators were combined so that the random number calls used in our library could still return the same sequence of numbers when initiated by our old programs (never know when we might have to rebuild a new version of Centipede3D for the Dreamcast :-) ). In MTGO, random numbers are initialized by the game servers. When a new game is started, the random number state is seeded via /dev/random, which uses hardware delays for a source of true random data. In addition, whenever a packet is received from a user by the game server, the lower order bits of the system CPU's clock cycle counter are added into the random state. Shuffling is performed by swapping every card in the deck with a random other card in the deck. This is algorithm "P" for shuffling from Knuth. The book contains a formal analysis of its randomness. The 32 bit random values returned by the basic random number function are mapped into the appropriate range by fixed point multiplication. One of our programmers, Sergey, was not satisfied that the random number generator wasn't mana-screwing him, and so performed the following test: The shuffler has no idea what is a land and is not a land, so if there is any unnatural clumping of lands, it must be based upon the initial ordering of the deck. So he performed the following test: Create in memory a virtual deck of 20 "1"s, representing lands, and 40 "0"s representing non-lands. Put all the "lands" first and then all the "nonlands". Apply the shuffler. Perform the same test, except with lands and nonlands interleaved before shuffling. Perform each test multiple millions of times. After each test, count the sizes of land/non-land clusters and keep a running total of each. Compare the results from the millions of runs with the deck ordered with all lands together versus the interleaved one. The results were the same to within a minuscule fraction of a percent. In addition, he wished to verify that shuffling extra times would have no effect. If it did have an effect that would mean that the shuffle was insufficiently random. He performed this test and got the same statistics from one shuffle as from many.

The primary reasons people think the shuffler isn't random:
• Most people are under the misconception that a random distribution means an even distribution. Random distributions have natural clustering.

• Experience doesn't match what they are used to in paper; there are many poor (human) shufflers out there. When confronted with *actual* randomness of the computer shuffler, they blame the computer instead of their own faulty shuffling practices. In reality these people have been unknowingly cheating for a long time.

• People tend to remember significant events more vividly then normal occurrences. They remember the times when they were horrifically flooded but forget all the normal games in between.

Now, some required reading before you post if you want any hope of people caring what you say:
• Stats 101: Am I Shuffling Enough - Or Correctly, For That Matter? - A very good explaination of what a randomized deck *should* look like; it's far different than many think. [Provided by Vitalogy]

• The Wikipedia Entry on Knuth Shuffling. Here's a code snipet using the method [adapted from code posted by many]:
deck = new Card[n] ; an array of Card objects n long (syntax: first element is element zero)
do i=0,n-1
swap = Random(i,n-1) ; random integer between i and n-1 (inclusive) generated as described by ChrisG
temp = deck[swap] ; store the card to swap into current position for a moment
deck[swap] = deck[i] ; move the current card where the swapped card was
deck[i] = temp ; move the swapped card where the current card was delete(temp) ; cleanup
delete(swap) ; cleanup
end do

• Actual OpenBSD code for a strong random number generator using hardware noise. Includes underlying theory [pointed out by slpalmer]

• Article describing similar complaints in bridge since they switched to computer-generated deals 30+ years ago. Turns out (suprise!) people weren't shuffling correctly so their expectations were wildly different than should occur with truely random deals. Also discusses how many shuffles are necessary to randomize a deck. [Provided by me]

• Math Magic Made Easy - Excel™ spreadsheet I created that computes various Magic math situations. One of the pages produces the probability of drawing so many cards of a certain type (listed as lands) out of N cards drawn from a deck of your choice. This should be useful if you want to try and disprove the shuffler by drawing a set number of cards from your deck instead of comparing the number of land clumps in the full deck as SCG does. [Shameless self-plug]

If you want to try and disprove the randomness of the shuffler, here are some things you MUST do:
• Use EVERY trial you do, don't pick-and-choose 'bad' ones and note them.

• Run a BARE MINIMUM of 1000 trials.

• Read up on statistical confidence intervals and learn how to conduct a T-Test, Z-Test or similar.

Xtofyr recorded data for several thousand hands. The initial results appeared skewed and prompted more thorough testing by elf. These later tests show the shuffler to behave as expected. Full results are here.

The probability for common MTG cases:

Seven Cards (opening hand):

 # land drawn 16/40 17/40 18/40 23/60 24/60 25/60 01.86% 01.31% 00.91% 02.67% 02.16% 01.74% 1 11.55% 09.20% 07.20% 13.84% 12.10% 10.51% 2 27.36% 24.55% 21.61% 28.56% 26.94% 25.22% 3 31.92% 32.30% 32.02% 30.29% 30.87% 31.18% 4 19.76% 22.61% 25.28% 17.82% 19.64% 21.44% 5 06.47% 08.40% 10.62% 05.80% 06.93% 08.19% 6 01.03% 01.53% 02.19% 00.97% 01.25% 01.60% 7 00.06% 00.10% 00.17% 00.06% 00.09% 00.12% 2-5 85.50% 87.85% 89.52% 82.46% 84.39% 86.02%

Six Cards (mulligan):

 # land drawn 16/40 17/40 18/40 23/60 24/60 25/60 03.51% 02.63% 01.97% 04.64% 03.89% 03.24% 1 17.72% 14.90% 12.35% 20.03% 18.07% 16.21% 2 33.22% 31.37% 29.16% 33.38% 32.47% 31.37% 3 29.53% 31.37% 32.74% 27.49% 28.87% 30.07% 4 13.09% 15.69% 18.42% 11.78% 13.37% 15.03% 5 02.73% 03.71% 04.91% 02.49% 03.07% 03.71% 6 00.21% 00.32% 00.48% 00.20% 00.27% 00.35% 2-4 75.84% 78.44% 80.31% 72.64% 74.71% 76.48%

Eleven Cards (5th turn play/4th turn draw):

 # land drawn 16/40 17/40 18/40 23/60 24/60 25/60 00.1080% 00.0585% 00.0305% 00.2495% 00.1753% 00.1217% 1 01.3574% 00.8413% 00.5035% 02.3378% 01.7801% 01.3392% 2 06.7869% 04.8074% 03.2920% 09.1842% 07.5820% 06.1810% 3 17.8157% 14.4222% 11.2870% 19.9518% 17.8719% 15.7958% 4 27.2476% 25.2389% 22.5739% 26.6024% 25.8834% 24.8220% 5 25.4310% 27.0205% 27.6531% 22.8266% 24.1578% 25.1644% 6 14.7232% 18.0137% 21.1465% 12.8399% 14.8064% 16.7763% 7 05.2583% 07.4493% 10.0697% 04.7247% 05.9490% 07.3445% 8 01.1268% 01.8623% 02.9149% 01.1117% 01.5323% 02.0656% 9 00.1366% 00.2660% 00.4858% 00.1588% 00.2404% 00.3547% 10 <0.0001% 00.0193% 00.0416% 00.0124% 00.0206% 00.0334% 11 <0.0001% <0.0001% <0.0001% <0.0001% <0.0001% <0.0001%

NB: booster/tournament packs are NOT random, nor are they intended to be. They are created using card listings called print runs.

If there is anything important you think I missed, let me know.

Credits: Everyone who has contributed their time to the rational discussion of the shuffler in various threads over the years.
Edit (23 Nov 05 19:05 UTC): Added 'Sweet-spot' total probabilities (at least 2 lands + 2 spells in opening hand) and probabilities for a mulliganed hand.
Edit (10 Jul 06 05:53 UTC): Added link to data provided by Xtofyr and Elf.
Edit (18 Jan 08 20:10 UTC): Updated FAQ reference
Edit (15 Mar 10 19:50 UTC): Reformatted with html tags

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Dual means two. A duel is a battle between two people. Lands that make two colors of mana are dual lands. A normal Magic battle is a duel.
Quotables

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"While a picture is worth a thousand words, each lolcat actually produces a negative wordcount." -Ith "I think "Highly Informed Sarcasm" should be our Magic Online General motto." -Ith "Sorry, but this thread seems just like spam. TT is for off-topic discussion, not no-topic discussion." -WizO_Kwai_Chang "Stop that! If you're not careful, rational thinking may catch on!" -Sax "... the only word i see that fits is incompitant." -Mr44 (sic) "You know a thread is gonna be locked when it gets to the hexadecimal stage." -Gathion "It's a good gig" - Gleemax "I tell people often, if you guys want to rant, you've certainly got the right to (provided you obey CoC/ToS stuff), and I don't even really blame you. But if you see something you think needs changing a well thought-out, constructive post does more to make that happen." - Worth Wollpert
crazyblend
Joined Dec 2003
2 Posts
No! Noooooooooo!!!
wizo_kwai_chang
Joined Nov 2004
199 Posts
Yes! Yessssssssssssss!!!

Thanks to bubba for compiling the vast knowledgebase that was present in the previous incarnation of the Shuffler thread. Hopefully it will help players understand how the shuffler works.

All we need now is Grog to chime in.
natedawg
Joined Nov 2003
5003 Posts
Credits: Everyone who has contributed their time to the rational discussion of the shuffler in various threads over the years.

I vote for giving entertainment credits to those who contributed irrationally. :D
4. Don't speak dumb, or you'll be struck dumb. Remember, the name of the game is heads I win, tails you lose.
bubba0077
Joined Feb 2002
10619 Posts
I vote for giving entertainment credits to those who contributed irrationally. :D

I usually just point and laugh.

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Unfortunately, VCLs do not currently have the tools necessary to take moderation actions directly. VCLs submit their actions to ORCs, who then actually perform the action. This processing can take between a few minutes and several hours, depending on how busy/attentive the ORCs are.

If you see something that needs VCL attention, please use this thread to make a request and a VCL will look at it as soon as possible. CoC violations should be reported to Customer Service using the "report post" button. Please do not disrupt the thread by making requests of either kind in-thread.

Dual means two. A duel is a battle between two people. Lands that make two colors of mana are dual lands. A normal Magic battle is a duel.
Quotables

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"While a picture is worth a thousand words, each lolcat actually produces a negative wordcount." -Ith "I think "Highly Informed Sarcasm" should be our Magic Online General motto." -Ith "Sorry, but this thread seems just like spam. TT is for off-topic discussion, not no-topic discussion." -WizO_Kwai_Chang "Stop that! If you're not careful, rational thinking may catch on!" -Sax "... the only word i see that fits is incompitant." -Mr44 (sic) "You know a thread is gonna be locked when it gets to the hexadecimal stage." -Gathion "It's a good gig" - Gleemax "I tell people often, if you guys want to rant, you've certainly got the right to (provided you obey CoC/ToS stuff), and I don't even really blame you. But if you see something you think needs changing a well thought-out, constructive post does more to make that happen." - Worth Wollpert
zinger314
Joined Aug 2002
1047 Posts
I break dance while I do the shuffle.

Is that a problem?
DrakeStorm
Joined Mar 2005
13 Posts
Shouldn't you mention how the Server is a sentient being and that eventhough over the course of millions of sample shuffles the results are random, but on any one game, the Server can and will mana-hose or mana-screw the non-believers as they see fit.

It's been a long time. DCI# 9325

tharion_wind
Joined Jul 2002
562 Posts
The Shuffler is broken. The shuffler is random. Human shuffling is better, more "realistic". The computer-based shuffler is truly random. Etc, ad naseum.

Grog is a pain to all of us. Either we just notice the manastarves/floods online more or it truly does impale us painfully.

I did some paper in 2002 and when we played - it was a 40% (24 land for 60 card deck) and never got manaflooded/starved as does happen in MTGO.

That being said, I played maybe 100 paper games then dove into MTGO. On average I do 100 MTGO casual games a week or more. So naturally wouldn't I get more flooded or starved with mana (by virtue of more games played)?

Inquiring minds would like to know the answer to this (and to those of you waiting to stamp 42 on this thread, I beat you to it).

Regards,
Tharionwind
Ponders if Grog ever could beat me in a PDC match.
Being challenged in life is inevitable, being defeated is purely optional. Improvise (a solution), Adapt (to current situation), Overcome (any obstacle in your way) -- been working for the USMC since 1776.
lathspel1
Joined Sep 2003
1000 Posts
Bubba, bringing back this thread should guarantee you an EPOTM. Just think of the evil you could summon when you're not being helpful. :evillaugh

Me, the more I play, the less I hate the shuffler. Either I'm getting used to it, I'm building my decks with the right land, or possibly I'm becoming a better mulliganer. Most likely it's that last one.
bubba0077
Joined Feb 2002
10619 Posts
Bubba, bringing back this thread should guarantee you an EPOTM. Just think of the evil you could summon when you're not being helpful.

Me, the more I play, the less I hate the shuffler. Either I'm getting used to it, I'm building my decks with the right land, or possibly I'm becoming a better mulliganer. Most likely it's that last one.

It's not like the former shuffler thread had vanished when I posted this (it was about the seventh non-sticky when I posted), I just thought it would be nice if a new one were started that had all the *good* technical information up front where everyone would see it. Not many people read every post in a 600+ post thread.

I'm (some would say unfortunately) firmly entrenched on the good team, and the evil team will NEVER pull me over to the dark side.

Now, if the naughty team had an opening...

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Unfortunately, VCLs do not currently have the tools necessary to take moderation actions directly. VCLs submit their actions to ORCs, who then actually perform the action. This processing can take between a few minutes and several hours, depending on how busy/attentive the ORCs are.

If you see something that needs VCL attention, please use this thread to make a request and a VCL will look at it as soon as possible. CoC violations should be reported to Customer Service using the "report post" button. Please do not disrupt the thread by making requests of either kind in-thread.

Dual means two. A duel is a battle between two people. Lands that make two colors of mana are dual lands. A normal Magic battle is a duel.
Quotables

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"While a picture is worth a thousand words, each lolcat actually produces a negative wordcount." -Ith "I think "Highly Informed Sarcasm" should be our Magic Online General motto." -Ith "Sorry, but this thread seems just like spam. TT is for off-topic discussion, not no-topic discussion." -WizO_Kwai_Chang "Stop that! If you're not careful, rational thinking may catch on!" -Sax "... the only word i see that fits is incompitant." -Mr44 (sic) "You know a thread is gonna be locked when it gets to the hexadecimal stage." -Gathion "It's a good gig" - Gleemax "I tell people often, if you guys want to rant, you've certainly got the right to (provided you obey CoC/ToS stuff), and I don't even really blame you. But if you see something you think needs changing a well thought-out, constructive post does more to make that happen." - Worth Wollpert
scaught
Joined Oct 2003
5 Posts
I just thought it would be nice if a new one were started that had all the *good* technical information up front where everyone would see it.

So why include the post from Chris Green? It's nothing but tech-speak cloaked misinformation and does more to harm LL's programming credibility and instill doubt into the legitimacy of the shuffler than it does to quash it.
zombiegleemax
Joined Aug 2009
469620 Posts
Uh oh! Zyto is going to be mad at you!!
He contacted me via pm a few days back asking me if it would be ok to make essentially this very thread. You have taken away his one chance at getting a thread started by him that would go over 100 posts.

I even fear his wrath.

/me goes into hiding.
bubba0077
Joined Feb 2002
10619 Posts
So why include the post from Chris Green? It's nothing but tech-speak cloaked misinformation and does more to harm LL's programming credibility and instill doubt into the legitimacy of the shuffler than it does to quash it.

Because it is the only original, official statement we have on the matter. Besides, I find it difficult to understand how you know there is misinformation unless you have access to the actual code.

Furthermore, I haven't been able to reconcile your complaints from the end of previous thread. Of course, it might help if I actually had a copy of Knuth to reference to see exactly what Algorithm A does. What I do know is random hardware and client packet information is commonly used in RNGs in other applications where actual randomness is important, such as virtual casinos, and I would think LL implemented a similar method.

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Unfortunately, VCLs do not currently have the tools necessary to take moderation actions directly. VCLs submit their actions to ORCs, who then actually perform the action. This processing can take between a few minutes and several hours, depending on how busy/attentive the ORCs are.

If you see something that needs VCL attention, please use this thread to make a request and a VCL will look at it as soon as possible. CoC violations should be reported to Customer Service using the "report post" button. Please do not disrupt the thread by making requests of either kind in-thread.

Dual means two. A duel is a battle between two people. Lands that make two colors of mana are dual lands. A normal Magic battle is a duel.
Quotables

Show
"While a picture is worth a thousand words, each lolcat actually produces a negative wordcount." -Ith "I think "Highly Informed Sarcasm" should be our Magic Online General motto." -Ith "Sorry, but this thread seems just like spam. TT is for off-topic discussion, not no-topic discussion." -WizO_Kwai_Chang "Stop that! If you're not careful, rational thinking may catch on!" -Sax "... the only word i see that fits is incompitant." -Mr44 (sic) "You know a thread is gonna be locked when it gets to the hexadecimal stage." -Gathion "It's a good gig" - Gleemax "I tell people often, if you guys want to rant, you've certainly got the right to (provided you obey CoC/ToS stuff), and I don't even really blame you. But if you see something you think needs changing a well thought-out, constructive post does more to make that happen." - Worth Wollpert
Xtofyr
Joined Jan 2004
2620 Posts
Uh oh! Zyto is going to be mad at you!!
He contacted me via pm a few days back asking me if it would be ok to make essentially this very thread. You have taken away his one chance at getting a thread started by him that would go over 100 posts.

I even fear his wrath.

/me goes into hiding.

It's cool. My FAQ was almost done -- I was just waiting for elf to get back to me on a few questions and I had e-mailed one of my university professors with some questions as well. But, bubba did a fine job.

Zyto
:coolcthul
I can't spare a moment for the dog faced boy I won't lend another hand to the worm girl of Hanoi Don't deplete my oxygen for the guy who's turning blue But ask me, and I'll do anything for you
scaught
Joined Oct 2003
5 Posts
Because it is the only original, official statement we have on the matter. Besides, I find it difficult to understand how you know there is misinformation unless you have access to the actual code.

If someone told you your car wasn't running properly because it's wiper fluid was low, would you need to know the inner workings of your engine to know that something was fishy with the assessment? What if it came from a mechanic? And what if you were a mechanic as well? Yes, my car needs wiper fluid, and I'm pretty sure it's important for things, but.....

Oh, there are words there that make sense. Whole concepts, too. But there are a bunch more words inbetween that boggle my mind. Sentences like:
The 32 bit random values returned by the basic random number function are mapped into the appropriate range by fixed point multiplication.

This is exactly what it sounds like when one of the producers here picks up a little programming lingo and tries to sound smart. "Fixed point multiplication"? For what? He wants to access fractional cards? (in other words, he's not dealing with whole numbers)? Or maybe he meant "fixed point with 0 precision"? And even if by "the appropriate range" he didn't mean the set of cards to choose from, why use fixed point math at all? On modern processors, you get none of the benefits (speed, memory) and all the drawbacks (severe loss of precision). Crazy moon talk.

Furthermore, I haven't been able to reconcile your complaints from the end of previous thread. Of course, it might help if I actually had a copy of Knuth to reference to see exactly what Algorithm A does. What I do know is random hardware and client packet information is commonly used in RNGs in other applications where actual randomness is important, such as virtual casinos, and I would think LL implemented a similar method.

My complaints might not even be valid because the "information" in that post doesn't make sense. That was my point. It's all conjecture. To beat my first analogy into the ground, I'm basically complaining that the wiper fluid offered to me is thin and doesn't clean the windshield well.

Anyways, hopefully elf will have shed some light on something to Xtofyr in such a way that will make this argument, this thread and the original post from Mr. Green moot and never referred to again.
bubba0077
Joined Feb 2002
10619 Posts
Oh, there are words there that make sense. Whole concepts, too. But there are a bunch more words inbetween that boggle my mind. Sentences like: This is exactly what it sounds like when one of the producers here picks up a little programming lingo and tries to sound smart. "Fixed point multiplication"? For what? He wants to access fractional cards? (in other words, he's not dealing with whole numbers)? Or maybe he meant "fixed point with 0 precision"? And even if by "the appropriate range" he didn't mean the set of cards to choose from, why use fixed point math at all? On modern processors, you get none of the benefits (speed, memory) and all the drawbacks (severe loss of precision). Crazy moon talk.

Unless of course the random numbers from the RNG are between zero and one, in which case you *do* need to do the multiplication in fixed-point before truncating to get a natural number. I'm not saying it's all crystal-clear, and clarification *would* be nice, but I didn't see anything patently wrong in there (and I program quite a bit). Besides, like I said, it is the only source document we have right now.

My complaints might not even be valid because the "information" in that post doesn't make sense. That was my point. It's all conjecture. To beat my first analogy into the ground, I'm basically complaining that the wiper fluid offered to me is thin and doesn't clean the windshield well.

Anyways, hopefully elf will have shed some light on something to Xtofyr in such a way that will make this argument, this thread and the original post from Mr. Green moot and never referred to again.

Information is always nice, but I wouldn't count on getting any back from Elf about the shuffler. He may not have even delved into it too deeply, since it was all done by LL long before he even had to deal with it. NOW, if we ask him about the code for 3.0, maybe he'll have some insight

Z2 => Sorry about pre-empting you here. I'd been thinking about redoing the shuffler thread for a couple weeks ago (I think I even mentioned *someone* doing it over in meta), but I don't think I discused it with more than a few people (none of them Jabs) and until I actually did it, it probably sounding more like wishful thinking. It's amazing the lengths I go to to procrastinate.

Show
Unfortunately, VCLs do not currently have the tools necessary to take moderation actions directly. VCLs submit their actions to ORCs, who then actually perform the action. This processing can take between a few minutes and several hours, depending on how busy/attentive the ORCs are.

If you see something that needs VCL attention, please use this thread to make a request and a VCL will look at it as soon as possible. CoC violations should be reported to Customer Service using the "report post" button. Please do not disrupt the thread by making requests of either kind in-thread.

Dual means two. A duel is a battle between two people. Lands that make two colors of mana are dual lands. A normal Magic battle is a duel.
Quotables

Show
"While a picture is worth a thousand words, each lolcat actually produces a negative wordcount." -Ith "I think "Highly Informed Sarcasm" should be our Magic Online General motto." -Ith "Sorry, but this thread seems just like spam. TT is for off-topic discussion, not no-topic discussion." -WizO_Kwai_Chang "Stop that! If you're not careful, rational thinking may catch on!" -Sax "... the only word i see that fits is incompitant." -Mr44 (sic) "You know a thread is gonna be locked when it gets to the hexadecimal stage." -Gathion "It's a good gig" - Gleemax "I tell people often, if you guys want to rant, you've certainly got the right to (provided you obey CoC/ToS stuff), and I don't even really blame you. But if you see something you think needs changing a well thought-out, constructive post does more to make that happen." - Worth Wollpert
Xtofyr
Joined Jan 2004
2620 Posts
Z2 => Sorry about pre-empting you here. I'd been thinking about redoing the shuffler thread for a couple weeks ago (I think I even mentioned *someone* doing it over in meta), but I don't think I discused it with more than a few people (none of them Jabs) and until I actually did it, it probably sounding more like wishful thinking. It's amazing the lengths I go to to procrastinate.

It's not a problem at all. After all, I did make swearage to Grog.

If elf tells me anything useful, I'll forward it to you for inclusion -- but yeah, I'm not holding my breath on that. I also e-mailed one of my former professors to parse Chris Green's statement for me. If she answers, I'll send that along too.

Zyto
:coolcthul
I can't spare a moment for the dog faced boy I won't lend another hand to the worm girl of Hanoi Don't deplete my oxygen for the guy who's turning blue But ask me, and I'll do anything for you
Caervel
Joined Oct 2005
151 Posts
Just an observation from something last night. I was playing around with making Ravnica decks with 'real' cards (obviously, since it isn't out on MTGO yet). Each deck had 23 spells and 17 lands. One deck I put all lands at the bottom, one type on top the other type below the first type (ie, all swamps together and all forests together). The other one I shuffled my lands first, then shuffled that pile into the spell pile. All shuffles I did were riffle (that's the only way I shuffle) and I did 7 each (what's needed to truly randomize a 60 card deck, so it should do just fine on a 40). Now note, I didn't intend to run an 'experiment', I just wanted to see how the created decks looked on the opening hand. I got _one_ acceptable opening hand out of 10 attempts. By acceptable, I mean more than 1 land and less than 6. I drew 1 land multiple times. I drew 6 land once, 5 land multiple times.

Had I managed these results on MTGO I might have started to believe that the shuffler was broken. I managed these results in real life. I got more mana screw/floods in 20 minutes last night in real life than I have on MTGO so far (probably triple the number of opening hands there).

So here's a possible challenge to those folks who think the shuffler's broken and have access to physical cards. Make the 'same' deck online and RL. It doesn't have to be exactly the same, but should have the same number of each color land and spells. ie, 10 swamp, 7 forest, 13 black spells, 10 green spells.

Keep a running total of the following for each MTGO game:

Number of each color spell in opening hand.
Number of each land in opening hand.
A letter code of F, N, S (for flood, normal, and screw)

Then riffle shuffle your physical deck at some point the number of MTGO games you've played so far, and note the same. Keep doing this. Compare results.
zombiegleemax
Joined Aug 2009
469620 Posts
A deck of playing cards is randomized by a procedure called shuffling to provide an element of chance in card games. Shuffling is often followed by a cut, to ensure that the shuffler has not manipulated the outcome.

Contents:
1 Shuffling techniques
1.1 Riffle
1.2 Stripping
1.3 Pushing
1.4 Pile shuffle
1.5 Beginner shuffle
2 False Shuffles
3 Shuffling machines
4 Randomization
5 Shuffling algorithms

Shuffling techniques:
Several techniques are used to shuffle a deck of cards. While some techniques achieve a better randomization than other techniques, other techniques are easier to learn and easier to handle or better suited for special situations.

Riffle:
The riffle shuffle (sometimes called a faro shuffle) is the traditional method of shuffling. The deck is divided approximately in half, one part going into the left hand and the other part going into the right hand. Then by riffling the thumbs over the edges of the cards, the two halves of the deck are interleaved together. With practice a person can sometimes achieve a perfect shuffle, with every other card coming from alternating hands. This is not recommended, as will be shown below. Sometimes, computer programs that shuffle cards do several riffle shuffles, rather than just determine each card at random.

One riffle shuffle reorders the cards significantly. But the reordering is not random, by any means. The top card is still near the top. The bottom card is still near the bottom. Most pairs of cards are either still adjacent to each other, or not very far apart. And so, several shuffles are necessary. How many shuffles? Mathematics shows that at least seven shuffles are needed to randomize the cards. More shuffles than that do not affect the randomness. Bridge players often complain about the poor hands that result from computer dealt cards. This would seem to indicate that these people are used to inadequate shuffling.

A perfect shuffle occurs when the deck is divided exactly in half, and the cards are perfectly interlaced, with one card coming from one hand, then one card coming from the other hand, then one card coming from the first hand, etc. There are two types of perfect shuffles, the "in-shuffle" and the "out-shuffle." Let's assume that the deck is divided in two with the top cards going into the left hand and the bottom cards into the right hand. Then an in-shuffle begins with the first card coming from the left, the second from the right, the third from the left, etc. An out-shuffle begins with the first card coming from the right. If the right hand originally took the top cards, then the definitions are reversed (the in-shuffle begins with the first card coming from the right...). It has been shown that eight perfect out-shuffles returns the 52-card deck to its original order. Apparently, it takes more in-shuffles to do that. So, perfect shuffles do not randomize a deck, far from it.

Stripping:
Another procedure is called stripping, where small groups of cards are removed from the top or bottom of a deck and replaced on the opposite side (or just assembled on the table in reverse order). This is a much less effective randomizing procedure, and is thus mainly used in conjuction with riffling, or by younger players whose hands are not large enough for other methods.

Pushing:
"Pushing" is the procedure of pushing the ends of two halves of a deck against each other in such a way that they naturally intertwine. Sometimes the deck is split into equal halves of 26 cards which are then pushed together in a certain way so as to make them perfectly interweave. This is known as a Faro Shuffle and is quite difficult to master.

Pile shuffle:
The pile shuffle is not a randomization technique, but a method to dissolve clumps of sticky cards. Cards are arranged in piles by putting the top card from the deck in turn on one of several piles. Then the piles are stacked on top of each other. This ensures that cards that were next to each other are now separated.

Beginner shuffle:
This involves simply spreading the cards out face down, and sliding them around and over each other with one's inexperienced hands. Then the cards are moved into one pile so that they begin to intertwine and are then arranged back into a stack. This method is useful for beginners and small children or if one is inept at shuffling cards. However, the beginner shuffle requires a large surface for spreading out the cards and takes longer than the other methods.

This is also used periodically in casinos, where it is called a "wash" or "scramble". A typical sequence between hands of poker, for example, is a wash, two riffles, a strip, a third riffle, and a cut, which an experienced dealer can accomplish in as little as five seconds.

False Shuffles:
Magicians, sleight-of-hand artists, and card cheats employ various methods of shuffling whereby the deck appears to have been shuffled fairly, when in reality the order of the cards stays exactly the same.

Shuffling machines:
Because standard shuffling techniques are seen as weak, and in order to avoid "inside jobs" where employees collaborate with gamblers by performing inadequate shuffles, many casinos employ automatic shuffling machines which perform continuous shuffles on a pack of cards, and can produce any number of cards on demand. Note that the shuffling machines have to be carefully designed, as they can generate biased shuffles otherwise: the most recent shuffling machines are computer-controlled.

Randomization:
The mathematician and magician Persi Diaconis is an expert on the theory and practice of card shuffling, and an author of a famous paper on the number of shuffles needed to randomize a deck, concluding that it did not start to become random until five good riffle shuffles, and was truly random after seven. (You would need more shuffles if your shuffling technique is poor, of course.) Recently, the work of Trefethen et al. has questioned some of Diaconis' results, concluding that six shuffles is enough. The difference hinges on how each measured the randomness of the deck. Diaconis used a very sensitive test of randomness, and therefore needed to shuffle more. Even more sensitive measures exist and the question of what measure is best for specific card games is still open.

Here is an extremely sensitive test to experiment with. Take a standard deck without the jokers. Divide it into suits with two suits in ascending order from ace to king, and the other two suits in reverse. (Many decks already come ordered this way when new.) Shuffle to your satisfaction. Then go through the deck trying to pull out each suit in the order ace, two, three ... When you reach the top of the deck, start over. How many passes did it take to pull out each suit?

What you are seeing is how many rising sequences are left in each suit. It probably takes more shuffles than you think to both get rid of rising sequences in the suits which were assembled that way, and add them to the ones that were not!

In practice the number of shuffles that you need depends both on how good you are at shuffling, and how good the people playing are at noticing and using non-randomness. 2–4 shuffles is good enough for casual play. But in club play, good bridge players take advantage of non-randomness after 4 shuffles, and top blackjack players literally track aces through the deck.

Shuffling algorithms:
In a computer, shuffling is equivalent to generating a random permutation of the cards. There are two basic algorithms for doing this, both popularized by Donald Knuth. The first is simply to assign a random number to each card, and then to sort the cards in order of their random numbers. This will generate a random permutation, unless two of the random numbers generated are the same. This can be eliminated either by retrying these cases, or reduced to an arbitrarily low probability by choosing a sufficiently wide range of random number choices.

The second, generally known as the Knuth shuffle or Fisher-Yates shuffle[1], is a linear-time algorithm (as opposed to the previous O(n log n) algorithm if using efficient sorting such as mergesort or heapsort), which involves moving through the pack from top to bottom, swapping each card in turn with another card from a random position in the part of the pack that has not yet been passed through (including itself). Providing that the random numbers are unbiased, this will always generate a random permutation.

Notice that great care needs to be taken in implementing the Knuth shuffle; even slight deviations from the correct algorithm will produce biased shuffles. For example, working your way through the pack swapping each card in turn with a random card from any part of the pack is an algorithm with nn different possible execution paths, yet there are only n! permutations. A counting argument based on the pigeonhole principle will clearly show that this algorithm cannot produce an unbiased shuffle, unlike the true Knuth shuffle, which has n! execution paths which match up one-to-one with the possible permutations.

Whichever algorithm is chosen, it is important that a source of truly random numbers is used as the input to the shuffling algorithm. If a biased or pseudo-random source of random numbers is used, the output shuffles may be non-random in a way that is hard to detect, but easy to exploit by someone who knows the characteristics of the "random" number source.
jerryvan
Joined Jun 2005
15 Posts
I stay up here at WotC HQ 24/7 365 and there are 3 reasons why I shuffle the cards the way I do.

1. I am capricious, benevolent one minute and malevolent the next. I sometimes like to give out perfect distribution for several games in a row, only to mana screw, or flood you at the least opportune moment.

2. As you read earlier I am here 24/7, 365 so I can nod off at times. I drink copious amounts of caffeine and consume large quantities of sugar to assure alertness, but sometimes I get just too tired and put something heavy on my keyboard while I doze off.

3. Some of you are simply blessed, and others are cursed. I have no say in it, it’s a universal convergence thing, and I carry out what the fates decree.

So now you know, its not math, its Magic.
lathspel1
Joined Sep 2003
1000 Posts
stuff

You left out the best way to shuffle: a big button labeled "Shuffle!". It makes everyone happy .
Ith
Joined Feb 2003
2374 Posts
I stay up here at WotC HQ 24/7 365 and there are 3 reasons why I shuffle the cards the way I do.

1. I am capricious, benevolent one minute and malevolent the next. I sometimes like to give out perfect distribution for several games in a row, only to mana screw, or flood you at the least opportune moment.

2. As you read earlier I am here 24/7, 365 so I can nod off at times. I drink copious amounts of caffeine and consume large quantities of sugar to assure alertness, but sometimes I get just too tired and put something heavy on my keyboard while I doze off.

3. Some of you are simply blessed, and others are cursed. I have no say in it, it’s a universal convergence thing, and I carry out what the fates decree.

So now you know, its not math, its Magic.

Ha!
mr_maigo
Joined Apr 2004
5 Posts
Here's all I have to say about the shuffler.

Some decks never get mana screwed (in any for) and some always do. Too me it seems a few cards is all it takes to go back and forth.
lawintern1
Joined Mar 2004
156 Posts
Here's all I have to say about the shuffler.

Some decks never get mana screwed (in any for) and some always do. Too me it seems a few cards is all it takes to go back and forth.

The problem is that those "few cards" you are talking about are lands! Of course a "few cards" make a difference. For instance, in limited 14 lands are usually too few while 18 lands are usually too many.
mr_maigo
Joined Apr 2004
5 Posts
*cough* I ment with out changing the amout of total card count or % of lands
vitalogy1994
Joined Feb 2002
83 Posts
*cough* I ment with out changing the amout of total card count or % of lands

But but... a green BigFattiesOnly deck and a white weenies deck doesn't need the same mana base.

Also, the use of mana fixing cards will influence a lot on the perception of mana screw.
firecrest
Joined Jul 2003
420 Posts
I don't mind the shuffler. That said, I'm convinced that some part of it, in some way, is not really random.

I understand that screw happens. And I don't mind. In fact, my beef isn't even with screw at all. I've noticed time and time again that some cards, in some decks, are just not seen. I'll put together a League deck and play 20 games in a week and then go to add a booster and see a card in my deck that I'd not seen once the whole week and had even forgotten was there. Then I'll change up the deck again and play a ton of new games and have the exact same thing occur with a new card. I often notice the same thing with my constructed decks. I'll put together a deck and play it a ton without changing it and see a single particular card about 1/10 as much as any other single particular card (Singleton decks are the easiest to notice this in).

But change up the deck just a little (add a card here, take a card out there) and presto. Your MIA comes up opening hand every game and some other lost soul pulls a vanishing act. I've honestly made minor changes to my League deck -just- because my bomb rare was the card that wasn't showing up and suddenly had it seeing play almost every game.

I've never heard anyone else complain of this, so perhaps it's just me. In fact, it -probably- is just me or a matter of complete perception. So don't think that I'm challenging the randomness of the shuffler. I really don't know enough about these things to even begin to do so. I'm just sharing my experience.
mr_maigo
Joined Apr 2004
5 Posts
Arg! Same decks, just like 3 cards diffrent, basic 20/40 setup.

STOP PICKING ON ME!!!
zombiegleemax
Joined Aug 2009
469620 Posts
I used to get mad at the shuffler all the time. But lately it really hasn't been an issue. Yeah you occasionally get screwed despite everything, but that happens to everyone. I notice it in opponents more nowadays, to be honest. I think what has happened is I've become a better deckbuilder. At least, that's what I like to tell myself Maybe I've become more mellow / laid back, though I'm pretty sure that isn't it, now that I'm in my 2nd year of medschool and it's like 100x harder than last year....
thevoor
Joined Jul 2005
116 Posts
I agree with Firecrest on this issue. The scenario described by him happens to me quite often exactly as he described above.

Also another issue I have had in the past shows there is some kind of discrepancy with randomness.

In the 5th Dawn release league, I had two of the skyreach mantas in my deck. I would be very happy to draw one of them as I knew with utter certainty that my next draw was going to be my other skyreach manta.

I noticed they were right next to eachother every single game and to test the theory, I would draw my deck until I saw them after each game. There was literally not one time where they were not right next to eachother, not once. That doesn't sound truly random to me.

When playing paper cards, I get mana screwed/flooded on a regular basis averaging out to one game in five or six. I don't seed my lands (disperse them evenly throughout the deck) ever and do a combination of pile shuffle, stripping and pushing. Online, i can play 12 games and get either mana screwed or flooded in eight of those games. Then, I will change my deck around and promptly go through a stretch of normal mana screw/flood that resembles my paper based stats.

So, my completely un-scientific opinion is that something is not "truly" random.
lawintern1
Joined Mar 2004
156 Posts
Arg! Same decks, just like 3 cards diffrent, basic 20/40 setup.

STOP PICKING ON ME!!!

Sorry to have to quote you again, but anytime you use a "basic 20/40 setup" you are just begging for mana problems (presuming that you aren't playing some sligh build that curves out at 3cc).

Since the shuffler algorithym doesn't differentiate between "types" of cards (meaning that the shuffler algorithym doesn't KNOW that a given card is land/non-land or bomb/non-bomb), it would be impossible for an exchange of one non-land card for another non-land card to influence your land draws.
mr_maigo
Joined Apr 2004
5 Posts
Sorry to have to quote you again, but anytime you use a "basic 20/40 setup" you are just begging for mana problems (presuming that you aren't playing some sligh build that curves out at 3cc).

Since the shuffler algorithym doesn't differentiate between "types" of cards (meaning that the shuffler algorithym doesn't KNOW that a given card is land/non-land or bomb/non-bomb), it would be impossible for an exchange of one non-land card for another non-land card to influence your land draws.

And yet that seems to be the case :P
zombiegleemax
Joined Aug 2009
469620 Posts
Pretty much the entirety of the original post was to try to prove the randomness of the shuffler. My contention has never been with that argument. In fact lets just streamline this thread by eliminating the 90% of posts that try to argue that. This however does not solve the shuffler issue, because I contend the reason the shuffler is 'busted' and needs to be looked at is because I am willing to say for the sake of argument that the shuffler IS completely random.

Look, even in the op, they state that complete randomness is more inclined to generate clusters ......HELLO?!
If nothing else that should end the discussion right there. Anyone who has played magic knows that a playable game of magic and large clusters cannot coexist. Its as simple as that. In fact the game of magic should do everything in its power to expunge clusters anywhere near its playing field if it can. So given that playable magic should not be anywhere near large clusters, the randomness of the shuffler on mtgo has set the game back.

I've said it before and I'll surely say it again. The imperfections of the human shuffle was an unintentional yet monumental boon to the early game of magic. The hidden beauty of the human shuffle is with it not being 'truly' random it will much less likely generate these clusters, yet is random enough that you still don't know whats going to come off the top. I further contend that the early game of magic might not have taken off near as much as it did if it had to accomodate true random play that is generated by the shuffler. Yes, gaming die hards would surely marvel at the beauty of design and how the game can be played in theory (as well they should, magic is one of the best games ever designed), but it would have been much harder for people to accept the actual playability of the game.

Also let's debunk some of the assertions made in the op. The suggestion that you only remember the bad hoses, but don't remember the playble hands. Ok, first off, lets not presume what it is that I remember playing. Secondly, believe me, I DO remember the hands that play nicely--even those that just play normal, they seem to come by so infrequently that I relish and savor the experience like fine wine, and gives hope that some solution can be found. Yes I will recall the bad ones too, but they happen much too frequently, and my already beat up keyboard and monitor suffers as a result. Look, I played all weekend at the RAV prerelease, and during that time I mulliganed once. Furthermore I never once drew more than 5 lands in a row, and I was deliberately shuffling my deck at least 7 times or more.. Ok, I admit this outcome was probably defying the averages for the good, but the point is clusters just happen so much less than when compared to the shuffler on mtgo. It obvious that there's something to this, the fact that there is a sticky thread dedicated to the shuffler tells you something. Compare the threads on shuffling and the randomness of the game on the mtgo boards to the regular magic boards.....I mean its like a 50.1 ratio. Yes, every once is a while you'll get the post of how someone missed out on top 8 my getting mana flooded, but you get a daily barrage of posting on the mtgo boards, and that is simply because its a daily occurrence.

The second point that I reject utterly is the assertion that because of the imperfection of the human shuffle that all this time players have been (and are currently) unknowingly cheating. Ok this is a croc. You have to throw the dirty word of cheating and all its connotations in there just to legitimize the 'truly' random approach. One could read into what you're saying is that every person who ever played real magic is a cheater, from pro tour level to the casual gamer. Well if this is the case, we know what wizards policy is on cheating, so might as well just stop making the game. Cause Im pretty sure that 99.9999999999% of the players in real magic use a human shuffle to shuffle their deck.

g
electroclash
Joined Aug 2004
7 Posts
semi-related question : do online magic cards have unique serial numbers ?
bubba0077
Joined Feb 2002
10619 Posts
Pretty much the entirety of the original post was to try to prove the randomness of the shuffler. My contention has never been with that argument. In fact lets just streamline this thread by eliminating the 90% of posts that try to argue that. This however does not solve the shuffler issue, because I contend the reason the shuffler is 'busted' and needs to be looked at is because I am willing to say for the sake of argument that the shuffler IS completely random.

Look, even in the op, they state that complete randomness is more inclined to generate clusters ......HELLO?!
If nothing else that should end the discussion right there. Anyone who has played magic knows that a playable game of magic and large clusters cannot coexist. Its as simple as that. In fact the game of magic should do everything in its power to expunge clusters anywhere near its playing field if it can. So given that playable magic should not be anywhere near large clusters, the randomness of the shuffler on mtgo has set the game back.

I've said it before and I'll surely say it again. The imperfections of the human shuffle was an unintentional yet monumental boon to the early game of magic. The hidden beauty of the human shuffle is with it not being 'truly' random it will much less likely generate these clusters, yet is random enough that you still don't know whats going to come off the top. I further contend that the early game of magic might not have taken off near as much as it did if it had to accomodate true random play that is generated by the shuffler. Yes, gaming die hards would surely marvel at the beauty of design and how the game can be played in theory (as well they should, magic is one of the best games ever designed), but it would have been much harder for people to accept the actual playability of the game.

Also let's debunk some of the assertions made in the op. The suggestion that you only remember the bad hoses, but don't remember the playble hands. Ok, first off, lets not presume what it is that I remember playing. Secondly, believe me, I DO remember the hands that play nicely--even those that just play normal, they seem to come by so infrequently that I relish and savor the experience like fine wine, and gives hope that some solution can be found. Yes I will recall the bad ones too, but they happen much too frequently, and my already beat up keyboard and monitor suffers as a result. Look, I played all weekend at the RAV prerelease, and during that time I mulliganed once. Furthermore I never once drew more than 5 lands in a row, and I was deliberately shuffling my deck at least 7 times or more.. Ok, I admit this outcome was probably defying the averages for the good, but the point is clusters just happen so much less than when compared to the shuffler on mtgo. It obvious that there's something to this, the fact that there is a sticky thread dedicated to the shuffler tells you something. Compare the threads on shuffling and the randomness of the game on the mtgo boards to the regular magic boards.....I mean its like a 50.1 ratio. Yes, every once is a while you'll get the post of how someone missed out on top 8 my getting mana flooded, but you get a daily barrage of posting on the mtgo boards, and that is simply because its a daily occurrence.

The second point that I reject utterly is the assertion that because of the imperfection of the human shuffle that all this time players have been (and are currently) unknowingly cheating. Ok this is a croc. You have to throw the dirty word of cheating and all its connotations in there just to legitimize the 'truly' random approach. One could read into what you're saying is that every person who ever played real magic is a cheater, from pro tour level to the casual gamer. Well if this is the case, we know what wizards policy is on cheating, so might as well just stop making the game. Cause Im pretty sure that 99.9999999999% of the players in real magic use a human shuffle to shuffle their deck.

g

• Whether or not true randomization is good for the game is an opinion, and as such did not belong in the OP that includes a recap of all the *factual* information on the shuffler, which is what MOST people want to contest.
• It *is* possible to shuffle correctly to produce a sufficiently randomized deck; the point is most people do not.
• Arguing over the desirability of true randomization for the game of Magic is fine, but the rules currently state your deck should be random. If you are not correcty randomizing your deck then you are at best not playing Magic correctly, and at worst cheating.
• Congratulations on accurately remembering every hand you draw, regardless of quality. Most people do not. Do not claim the assertion is wrong just because it is not true for you.
• The previlance of complaints on the MTGO side has nothing to do with random being worse for the game; it is the result of two main factors, either seperate or combined: poor expectation of what random is and the loss of control because the computer does it. In paper, there *IS* nothing to argue besides the value of randomization vs. not.

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lawintern1
Joined Mar 2004
156 Posts
The more I have thought about the shuffler, the more I am convinced that, if there is a flaw (and I don't believe there is), it would have to be with the random number generator. Let me also say that I am, admittedly, not trained in mathematics (I finished Calculus in highschool, but haven't taken a math or mathematics based couse since). I grasp the rudiments of statistics (I think), but little beyond that.

In rereading the original statement describing the shuffler program, I have focused on this section:
The implementation of this generator used in our libraries uses the standard constants (24,55). Because this is somewhat fewer than the number of bits required to produce all possible hands, it was augmented with another generator using the constants (33,68). This yields a total state size of 3936 bits. Both generators were combined so that the random number calls used in our library could still return the same sequence of numbers when initiated by our old programs (never know when we might have to rebuild a new version of Centipede3D for the Dreamcast :-) ).

In MTGO, random numbers are initialized by the game servers. When a new game is started, the random number state is seeded via /dev/random, which uses hardware delays for a source of true random data. In addition, whenever a packet is received from a user by the game server, the lower order bits of the system CPU's clock cycle counter are added into the random state.

Would someone please explain this in plainer language, if possible, with special attention to how the game servers and the purchase of packs influence the number being generated? If there are fewer games being played or packs being purchased, will this have any impact on the random number that is being generated?

In the end, my understanding is that the random number generator doesn't have to be truly random as long as it is sufficiently random to make the shuffler algorithym operate correctly. Am I right?
zombiegleemax
Joined Aug 2009
469620 Posts
I agree with you Grungeworth, you have said exactly what I have been feeling since online. I don't and never have wanted a computer shuffler that creates the most accurately representation of a perfectly randomized deck, and if players understood this more deeply neither would they. what everyone should want is a computer program that recreates to the best of its ability a shuffle that a human would make, which while fairly good, isnt going to be a perfect randomization. the real world isnt perfect, and mtgo strives in every aspect to try and make the online game as similar to the real game, so why not have the shuffler be as close to a human shuffle as possible. i know some casinos use interleaving riffle shuffle programs that simulate a real world dealers shuffle... they probably run it 4-7 times to sufficiently randomize. why cant mtgo do this?
akawie
Joined Sep 2002
17 Posts
i know some casinos use interleaving riffle shuffle programs that simulate a real world dealers shuffle... they probably run it 4-7 times to sufficiently randomize. why cant mtgo do this?

Why do you think that the outcome would be different if MTGO shuffled in this manner? If that shuffling method sufficiently randomizes the deck then there should be no difference from the current situation.

Most of the suggestions to "fix" the shuffler call for some sort of artificial "mana weaving". That is not a good idea.
firecrest
Joined Jul 2003
420 Posts
Would someone please explain this in plainer language, if possible, with special attention to how the game servers and the purchase of packs influence the number being generated? If there are fewer games being played or packs being purchased, will this have any impact on the random number that is being generated?

Now THAT'S a lawyer for ya. As a compu-geek, reading this almost caused me to bust a gut. No offense intended. I can totally see how you thought what you did, not knowing the terminology.

The quote you referenced said 'packets', not packs. A packet is a very small amount of information passed between connected computers. If you've ever heard the term 'ping' to test the relay speed between servers, what is basically happening is it's timing the speed that the packets are being sent.

The quote isn't claming that game numbers and packs purchased have anything to do with ths shuffler. What it is basically saying is that when the game is started, it uses packet speed/size and other stuff from your computer to provide the base for its random number generating. To be very specific, I think it's saying that it takes out a certain chunck of numbers from the measured speed (this number is insanely precise and constanly fluctuating) with which your computer happens to be communicating with the server at the opening of the game as part of (maybe the start of) its random number generator. To be even MORE specific, it looks like the number that counts comes from the speed with which the server receives a packet from your computer.
lawintern1
Joined Mar 2004
156 Posts
The quote isn't claming that game numbers and packs purchased have anything to do with ths shuffler. What it is basically saying is that when the game is started, it uses packet speed/size and other stuff from your computer to provide the base for its random number generating. To be very specific, I think it's saying that it takes out a certain chunck of numbers from the measured speed (this number is insanely precise and constanly fluctuating) with which your computer happens to be communicating with the server at the opening of the game as part of (maybe the start of) its random number generator. To be even MORE specific, it looks like the number that counts comes from the speed with which the server receives a packet from your computer.

[mobster accent]What am I? A clown for your amusement?[/mobster accent] Seriously, I assumed that the programmer wasn't that familiar with game terminology, so he used the term "packet" where I would have used the term "pack." :D Glad someone knows what's going on around here.

I presume that by "insanely precise and constantly fluctuating" you are saying that the number is completely random. This makes some sense to me, but I can imagine a scenario (dramatically oversimplified for the sake of this question) where a number was constantly fluctuating between 1 and 10. Accordingly, even though this number would be random, it might not be random enough to account for the 60! permutations of a deck. I think the language:
The implementation of this generator used in our libraries uses the standard constants (24,55). Because this is somewhat fewer than the number of bits required to produce all possible hands, it was augmented with another generator using the constants (33,68). This yields a total state size of 3936 bits. Both generators were combined so that the random number calls used in our library could still return the same sequence of numbers when initiated by our old programs ...

addresses my question. I just don't understand what this means. Again, if this is really simple, I'm not trying to be intentionally dense ...
sax
Joined Jul 2002
709 Posts
I contend the reason the shuffler is 'busted' and needs to be looked at is because I am willing to say for the sake of argument that the shuffler IS completely random.

Look, even in the op, they state that complete randomness is more inclined to generate clusters ......HELLO?!
If nothing else that should end the discussion right there. Anyone who has played magic knows that a playable game of magic and large clusters cannot coexist.

Why not? The randomness of the deck and the chance of drawing "3 lands in a row" is part of the game. A non-randomized deck without clusters might as well be "pile of lands shuffled" and a "pile of non-lands" shuffled and you pick which one you draw from. That's not Magic.

Its as simple as that. In fact the game of magic should do everything in its power to expunge clusters anywhere near its playing field if it can. So given that playable magic should not be anywhere near large clusters, the randomness of the shuffler on mtgo has set the game back.

As has the requirement that people actually shuffle their decks (in paper magic). C'mon. You're just being ridiculous.

I've said it before and I'll surely say it again. The imperfections of the human shuffle was an unintentional yet monumental boon to the early game of magic. The hidden beauty of the human shuffle is with it not being 'truly' random it will much less likely generate these clusters, yet is random enough that you still don't know whats going to come off the top. I further contend that the early game of magic might not have taken off near as much as it did if it had to accomodate true random play that is generated by the shuffler. Yes, gaming die hards would surely marvel at the beauty of design and how the game can be played in theory (as well they should, magic is one of the best games ever designed), but it would have been much harder for people to accept the actual playability of the game.

The imperfections of the human shuffler are what make it random. What you're talking about is "being too lazy to shuffle properly". Your argument is that it's good for the game. It is BAD for the game. Shuffling improperly is bad because someone will "improperly shuffle" in a way to get an advantage over someone who thinks that "shuffling properly" is the right way to play.

Also let's debunk some of the assertions made in the op. The suggestion that you only remember the bad hoses, but don't remember the playble hands. Ok, first off, lets not presume what it is that I remember playing. Secondly, believe me, I DO remember the hands that play nicely--even those that just play normal, they seem to come by so infrequently that I relish and savor the experience like fine wine, and gives hope that some solution can be found. Yes I will recall the bad ones too, but they happen much too frequently, and my already beat up keyboard and monitor suffers as a result.

Attention everyone! Grungeworth behaves in a manner different from the bulk of the human race! He remembers "the usual" in detail as well as "the unusual". Please contact the writers of psychology textbooks to insert special mention of Grungeworth, so their presumptuous generallizations don't include him. Thank you!

Look, I played all weekend at the RAV prerelease, and during that time I mulliganed once. Furthermore I never once drew more than 5 lands in a row, and I was deliberately shuffling my deck at least 7 times or more.. Ok, I admit this outcome was probably defying the averages for the good, but the point is clusters just happen so much less than when compared to the shuffler on mtgo.

My guess is it means you're not shuffling properly, even though you do it "7 times". Though it is possible you just got lucky.

It obvious that there's something to this, the fact that there is a sticky thread dedicated to the shuffler tells you something.

Look at all the websites talking about UFOs. And paranormal behaviour! And every newspaper prints horoscopes! This should tell you something!

Compare the threads on shuffling and the randomness of the game on the mtgo boards to the regular magic boards.....I mean its like a 50.1 ratio.

There IS a reason for this. On Mtgo people can blame their bad luck on something other than "luck". In paper magic you'd have to resort to "Intelligent Design" to explain clumps.

The second point that I reject utterly is the assertion that because of the imperfection of the human shuffle that all this time players have been (and are currently) unknowingly cheating. Ok this is a croc. You have to throw the dirty word of cheating and all its connotations in there just to legitimize the 'truly' random approach. One could read into what you're saying is that every person who ever played real magic is a cheater, from pro tour level to the casual gamer. Well if this is the case, we know what wizards policy is on cheating, so might as well just stop making the game. Cause Im pretty sure that 99.9999999999% of the players in real magic use a human shuffle to shuffle their deck.

Cheating is only if you KNOW you're not shuffling properly and continue to do it. I'm sure most people shuffler (or try to) adequately. You don't seem to want to. Draw your own conclusions.