[Mini-Guide] Mabinogi Repair % System Is a Lie?

• Cide wrote on 2010-05-11 05:50

  Quote from Andy-Buddy;33230:

  Holy Water cuts the % of loss in half.
  i. e. 90% -> 95%
  95% -> 97.5%
  98% -> 99%
  
  We were just looking at the chance of a perfect repair, at different points of time. Blessing failures, and losses are not counted in what we are looking for.

  
  
  is there any source out there to actually confirm this? i've yet to see a solid source but i've heard this a lot.
• Syrphid wrote on 2010-05-11 07:41

  Quote from Jahrakal;33139:

  [SIZE="4"]Difference Between Perfect Repairs and Point-by-Point Repairs.[/SIZE]
  
  If you do perfect repair (meaning attempting to repair all points at once), your success rate drops dramatically, resulting in almost a guaranteed failure. This is why a lot of players use point-by-point repairs.
  
  Example:
  
  Let's say you're trying to repair 0/10 dagger, blessed/non-blessed is irrelevant for this discussion.
  
  If you do point-by-point, your repair sequences and rates are like this.
  

  
  
  • 98% -> 98% -> 98% ->.... -> 98% -> 98%
    

  
  
  If you choose perfect repair, it looks more like this.
  
  

  
  
  • (98% 98% 98% ... 98% 98%)
    

  
  
  
  On perfect repairs, the system overlaps the subsequent repair rate followed by the first attempt.
  
  
  For easier understanding:
  
  [98%] -> [98% of 98%] -> [98% of 98% of 98%] -> .... -> [98% of 98% of 98% of... 98%]
  
  Each arrow representing each point in durability when you're using perfect repair.
  
  See the problem here? The chances decrease the more durability loss you have. Therefore, items with 0/5 durability have way higher success rate than the ones with 0/30 durability, using the perfect repair.
  
  Example: At 98% repair, using perfect repairs
  
  Dura : Success Rate
  0/1 : 98% chance to fully repair (This is the same as point-by-point repairs)
  
  0/5 : 90% chance to fully repair
  0/10 : 81% chance to fully repair
  0/15 : 74% chance to fully repair
  0/20 : 67% chance to fully repair
  0/25 : 60% chance to fully repair
  0/30 : 55% chance to fully repair
  
  
  Following is an analogy irrelevant to probability, but explanation of the concept of why the rates are like that:
  
  Think of 30 cars trying to park in 30 different spots all lined up side by side all at once. - Perfect Repair
  Think of 30 cars lining up in 1 line to fill up 30 spots 1-by-1. - Point by Point
  
  
  To sum it up, if you attempt perfect repairs at low durability, you are pretty much guaranteed to fail a point.
  
  I will not mention the effects of Holy Water and rainy days, as they have very little to do with my topic.
  
  Cheers.

  
  
  First, thanks for posting your guide. Always good to see new stuff.
  
  I don't understand the quoted though. Are you saying that full repair has lower dur loss rate? I don't think that's true. Full repair is just single point repair lumped together. On average you would still lose the same amount of dur.
  
  All you're doing is showing how 0.98^n drops down over time. n=30 for both 30 pts full repair and 30 pts point repair.
• Phunkie wrote on 2010-05-11 11:41
  Full repair and point-by-point repairs are the same.
  
  The reason why people use point-by-point repairs is that they can re-bless the item if the repair fails.
  
  You cannot re-bless the item when you fail in a full repair. So if you're repair 4 durability points and you fail on the second (using full repair), you have a lower chance of repairing the next points after that.
  
  Full repair example:
  
  Item is blessed
  -> (Repair 1 pt.) Blessed
  -> (Failed 1 pt.) Unblessed
  (Lower chance of success now since item is unblessed)
  -> (Lower chance of repair) Unblessed
  -> (Lower chance of repair) Unblessed
  
  
  However, in a point-by-point repair, you can stop in-between repairing points to bless, just in case you fail 1 pt.
  
  Point-by-point example:
  
  Item is blessed
  -> (Repair 1 pt.) Blessed
  -> (Failed 1 pt.) Unblessed
  (Bless the item, proceed on repairing)
  -> (Higher chance of repair due to bless, but you can still fail again)
  -> (Bless again if you fail, continue on if you don't)
  -> etc., etc.
  
  
  With that said, if you never bless your items, point-by-point repairs and full repairs are completely identical. It doesn't matter which one you do.
  
  0.98^n applies to any of them in that case because the probability is the same.
  
  
  The OP should include a section on blessings and Holy Waters.
• Raj wrote on 2010-05-11 23:09
  Did I see a double post?!~
  
  And - Erm, I don't like all the math.
  >.>
• Phunkie wrote on 2010-05-11 23:16
  It's pretty much just punching numbers in your calculator. That's not real math.
• Raj wrote on 2010-05-11 23:22
  Oh. o.o
  I don't have a calculator.
• Rime wrote on 2010-05-12 01:51

  Quote from Phunkie;33337:

  Full repair and point-by-point repairs are the same.
  ...
  ...
  ...
  0.98^n applies to any of them in that case because the probability is the same.
  
  
  The OP should include a section on blessings and Holy Waters.

  
  
  This is only true if you're looking at the situation from before any points are repaired.
  
  If you are repairing your weapons point by point your frame of reference shifts to before the repair of the next point, but after the repair of the last point, so the success rate of the next 1 point of repair is always the success rate mentioned by the black smith.
  
  For instance, let's say I'm repairing a 0/3 broadsword at Erden, un-blessed. The chance of success for the first point is 98%. I click "repair one point" and it succeeds. My frame of reference is now after the successful attempt of repairing 1 point, so the success rate of the next 1 point from my current frame of reference is also 98%. Let's say the second point also succeeds. My frame of reference is now between the second and third attempt in which the first and second attempt succeeded. It follows now that the success rate of the third point from my current frame of reference is still 98%.
  
  Full repairs are, by nature, different because the game calculates the probability of success of all points at once.
  
  Let's take the same situation from above and assume that I'm much too lazy to click three times, and have resigned to only do so once for a full repair. Below, I'll show you how the system will treat the well-being of my broadsword.
  
  Scenario 1: Loss of no points There's only one way this can happen, and that is if no points fail.
  .98 x .98 x .98 = .941192
  
  Scenario 2: Loss of one point. There are three ways in which one point can be lost. The first point can fail or the second or the third. For the sake of simplicity, I'll write it out this way:
  
  [Fail][Success][Success]
  
  [Success][Fail][Success]
  
  [Success][Success][Fail]
  
  The probability of each one of these cases occurring is:
  
  .02 x .98 x .98= .019208
  .98 x .02 x .98= .019208
  .98 x .98 x .02= .019208
  
  The probability of losing one point taking these three scenarios into consideration is, simply, the sum of the three which equals .057624
  
  Scenario 3: Loss of two points. There are three ways in which I can lose two points. I'll write them out below:
  
  [Fail][Fail][Success]
  
  [Success][Fail][Fail]
  
  [Fail][Success][Fail]
  
  .02 x .02 x .98 = .000392
  .98 x .02 x .02 = .000392
  .02 x .98 x .02 = .000392
  
  Chance of losing 2 points = 3x .000392 = .001176
  
  Scenario 4: Loss of all 3 points There's only one way this can happen. It is, obviously, if none of the points succeed.
  
  [fail][fail][fail]
  
  .02 x .02 x .02 = .000008
  
  Data check:
  .941192 + .057624 + .001176 + .000008 = 1
  No scenarios were overlooked.
  
  The big picture:
  The system calculates all the above scenarios faster than you can muster them, and treats your weapon accordingly. So, to predict the results of the full repair of my broadsword, let's restate the information above as something more understandable.
  
  As calculated from above:
  Possibility of no points lost = .941192, which is also equal to 94.1192%
  
  Possibility of 1 point lost = .057624 or 5.7624%
  
  Possibility of 2 points lost = .001176 or .1176%
  
  Possibility of all points lost = .000008 or .0008 %
  
  If I choose "full repair" for my broadsword, there will be a 94.1192% chance that no points will fail and the sword will be at 3/3 dura; a 5.7624% chance that one point will fail, leaving the sword at a paltry 2/2 dura; a .1176% chance that two will be lost, making the sword almost unusable; and finally, a .0008 % chance that three points will be lost, leaving me with a completely broken 0/0 broadsword.
  
  Compare this to point by point repair at Erden, in which the next point will always succeed at a promised 98%.
  
  Take this however you will, cause I'm too tired from typing all this data to give you my opinion. Also, side note: I haven't taken stats in like, forever, so the terminology might be a bit awkward, or even incorrect.
• Taran wrote on 2010-05-12 02:13

  Quote from Jahrakal;33139:

  
  
  This is not % system's fault, but your lack of knowledge on how probability works.
  
  

  
  
  
  *yawns at thread*
  
  So explain why i failed 3/4 times (fail-fail-success-fail in a row) at 99% making silks? Either Mabinogi % system is broken or during that minute all odds were against me.
• Mentosftw wrote on 2010-05-12 02:26
  ^ Probability. 99% does not equal 100%. That slim chance is still a prominant factor in getting a failure. You have to realize that the difference and distance between 99% and 100% is extremely great.
• Kazuni wrote on 2010-05-12 02:42
  What Phunkie said...
  
  Point by point is for blessing in between in case of failure. There's no % difference in the repair itself.
  
  eg.
  
  98^n isn't a formula for the % of success you get for an all point repair or whatever, it's for both (1 point and perfect), over time. I don't see the point of all these calculations. It's the same.
• Mentosftw wrote on 2010-05-12 02:51
  It's different because of the way the game system calculates it.
  Point by point works with odds stacked in the real word where the odds ARE stacked but counted for in real life.
  What I mean is that the game system takes each point by the specified repair rate one at a time but the odds of all your points repaired will be dependant (although each point will not affect each other's rate but when all the rates combined will be a single rate).
  Perfect is different because the system already calculates the combined probability of all the repairs internally and then applies it to the repair.
  Therefore, technically both probabiliy outcomes for point by point and perfect are the same, because they are applied differently, it's different. If you were somehow able to go back in time and replay the same repair (item must be over 1 point of damage), only to either select perfect or point by point, the result would be different.
  Sorry for the crappy explaination.
• Kazuni wrote on 2010-05-12 03:00
  No, but still. They calculate it with the correct math, which would initially be the same as if you did point by point.
  
  You may get different results should you go back in time, but if you were to pick a coloured marble out of a bag you might also get different results.
  
  In the end, unless devcat is purposely screwing, which would be hard to prove at any rate, the % should be the same for both point by point and perfect no matter how you calculate it.
• Rime wrote on 2010-05-12 03:06

  Quote from Kazuni;34006:

  No, but still. They calculate it with the correct math, which would initially be the same as if you did point by point.
  
  You may get different results should you go back in time, but if you were to pick a coloured marble out of a bag you might also get different results.
  
  In the end, unless devcat is purposely screwing, which would be hard to prove at any rate, the % should be the same for both point by point and perfect no matter how you calculate it.

  
  
  Depends on whether or not they round the percentages or the RNG that deals with the randomness, I think. RNGs are never completely random...
• Mentosftw wrote on 2010-05-12 03:27
  Well, as for the going back in time thing, I have a real life example. This deals with two games on a GBA emulator, Super Robot Wars OG 1 and 2. As all of you may know, there is a % chance for all battle encounters. The difference is that OG 1's % calculator always has a fixed outcome for every encounter even with save states that allow you togo back to the moment where you created the savestate or "go back in time". Every time that savestate is loaded, the outcome is always the same even if the percentage is 50%. However, with OG 2, every time you loaded the savestate and replayed the encounter, it would always be different. There is obviously a fixed outcome and not a completely random chance. The same goes with my first time travel example. In that time frame, that outcome will always be the same just like OG1 otherwise, we'd start talking about alternate time branches (I don't want to go there) like OG2 where I can replay the encounters to perfection leading to a game where I avoided everything and missed nothing. To get to the point, since point by point and perfect are two different options, they'd most likely lead to different results. To complement your coloured marble example, if you continiously watched yourself pick out from the same container in that same timeframe, you would find that you past self's hand will always move exactly the same way to always grab the same marble. It would be like there being TWO containers, both with fixed outcomes because of the consistancy of time but a different outcome over the other because of a different option.
• Kazuni wrote on 2010-05-12 03:33
  So what you're saying is that repair has a fixed outcome and % doesn't matter because it's fixed?
  
  And as a response to.. your response.. about the marble thing, it was just an example for the chance of going back in time, and the angle of the hand and possible influences are not considered factors, as repairing in mabinogi is purely electronic and not dependent on outside factors at all.