Reading discards?

[Referee]

Hi there. My level at Reach Mahjong is as follows: I know how to build a hand (sometimes I make ill choices to go for big hands, but that's another question). I know the yaku and stuff. I don't have much practice at counting score because the computer always does that by itself, and I don't have fellow face-to-face players. I know to avoid furiten, although ocasionally I still get hit by that. I don't usually open my hand, except for yakuhai, or if going for quick toitoi or hon itsu. I like to go for quick renchan as oya if possible.

Anyway, my big problem is I don't know well how to decide to break my hand, and if so, how to guess what the opponents are waiting for. I've been directed to the usual links about that, but the info is a bit overwhelming. So I'm thinking this might work.

I'm putting an example discards an opponent made at Saki-anime. I don't know if the example will be any good, but I'm trying to get a "real" example so I can look for pointers. Situation is East-2 0 tonba (Saki-anime does east only games). I'm sitting at West. South at my left had these discards.





Opponent called Riichi with the 4 wan. How would one go about, is opponent dangerous or not, and what tiles are to be avoided? I don't know what she was waiting for, since she ended up paying me for riichi pinfu haitei (I had riichi'd with pinfu only one turn earlier).

I hope people can learn something from this example (I have no clue if it is any good, as I said). Thanks for the insight of more acknowledgeable people.

PS: Dora, if it matters for anything, was 5 pin. Saki-anime has no red fives.

[Shirluban]

Her first row of discard shows a classic mentanpin hand (concealed, tanyao, pinfu). From this we can suppose she have a ryanmen wait and don't wait for an honor. Ones and Nines are more or less safe but can be tricky (_23_ is a good wait). If you need more explanations, please ask.

Knowing which comes from the hand and which are draw-discarded is an interesting information and may change the reading.
I suppose the second and the are draw-discarded.

You should focus on (it's the first "middle-tile" discard). Normally any tile between 3-7 is useful, why did she not need it?
You said the dora was 5 pin, so this 4 pin should be even more useful. She would never discard it without a very good reason (assuming she is not a total beginner).
Knowing if comes from the hand or not is a very valuable info. The interpretation of the would be completely different.

Same thing for the first , why he don't need it?
I suppose and at the second are draw-discarded. If it's the case, they are meaningless. If not, she may be not going for mentanpin, or maybe there is a "special" table situation (see other players' discards).


"what the opponents are waiting for"
You have to sort out which tiles are discarded for being useless in his hand (like 9 from 129), and which ones was useful but he find a better one (like from 223, 245, ...).
(I'm not sure this sentence is in valid English.)
Generally, useless tiles are discarded first and the more useful ones are discarded at the very end.
The last tile discarded from the hand, I suppose the here, is likely to be very close to the waiting pattern (ex: 344, 445). But it can be otherwise too (ex: 4567).

In fact, it's easier to find what the opponents are NOT waiting for.
He is not waiting for a tile he had discarded (furiten).
Assuming he will have a ryanmen wait, if he is not waiting for a 4, he is probably not waiting for a 1 and 7. Same with 5 and 2/8, and with 6 and 3/9.
Beware! If he is not waiting for a 1, you should NOT consider 4 to be safe. He can have 56 and wait for 4-7.

"how to decide to break my hand"
Are you waiting?
How much worth your hand?
How much seems to worth your opponents hands?
Did you have save tiles?
...

For the given situation, South hand seems to worth 4-5 han (I let you count ) and it's pretty much late in the game.
If you are not tenpai, you should break your hand.
If your hand worth more than a mangan and don't have any safe tile, you will continue your hand.
There is more to say, but I will stay here for tonight.


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Edit1: Oh! If my reading is right, I'm not quite sure why he riichi: it's late in the game and a 3-4 han hand is already good.
Maybe it really improves his hand value (3->4 han), or maybe he hope for ura-dora (5 han + ??? dora).
Maybe the exact situation can explain it (opponent's discards, score, rank, ...).


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Edit2: "she ended up paying me for riichi pinfu haitei (I had riichi'd with pinfu only one turn earlier)"
Hum?! That doesn't sound right!
1) You are West, riichi.
2) North plays.
3) East plays.
4) South plays, riichi.
5) You win by drawing the last tile of the wall (haitei).
Normally, it's not allowed to riichi if less that 4 tiles remain in the wall, so South make a fault.
Let's assume Saki rules allow that, their is no point in South's riichi: he bet 1000 points and his only way to win is calling the last tile (houtei).
Second problem: it's the 14th discard. If we are one tile before the end, it should be the 18th discard or so.

[b4k4ni04]

Also playing the mini game on Saki's website, I came across these discards:

The situation is East 2, dora is the 8 of dots. I am East, but we'll look at South's discards first:


* * (Reach)

The Green Dragon was stolen by west.

Now, what can we assume from these discards?
For south, we're not told much until we see the 6 and 4 of bamboo.
Everything else is standard edge(ish) discards. Going by 1-4-7 theory, the 2-5-8 of Bamboo might be dangerous, but I discarded a pair of 5's, and south's own discard of a 2 shows that bamboo is 90% safe to discard. Unless he's got a sneaky shanpon/twin-pair wait, you're safe with discarding a bamboo.

Mnn, that's all I can say for certain, In the end, All south had was Yakuhai, reach, dora with this hand:

So looking at 3+ han depending on tsumo, and ura-dora.

~~~~~~~~~~~~~Intermission~~~~~~~~~~~~~

Sadly for South, he didnt win the hand, I did >). My Discards:


(3, 2, or 1 char.)
(I forget and it's covered on the screen)

What do my discards say about my hand?
The 5's in dots and bamboo say a lot. First, the early 2 and the 5 in bamboo can say that I'm not looking for low numbered bamboo tiles. The 2nd 5 of bamboo doesn't say much more than the first 5. The 5 of dots is a glaring flag saying I must be close to tempai, or need absolutely nothing in dots. The 1 of bamboo adds to the bamboo picture saying all low bamboo are safe against me, the 3 of bamboo reinforcing that theory. For my hand I'd beware discarding any value above 5 in any suit, except maybe the 8's of dots and bamboo.

When north discarded the I won with Dealer Pinfu on this hand:


~~~~~~~~~~~~~Intermission the Second~~~~~~~~~~~~~

Ooh, Another tempai hand, lets look at West!
Discards:




Visible:
(Stolen on South's 3rd discard)

What is safe to throw?
Bamboo. The 7, 5, and 2, in the first 6 tosses. This guy has NO use for bamboo. The 3, then 5, character tiles are curious as well. We can't immediately conclude that it's a half-flush hand, but there is fairly strong evidence for it. Note that, West's call for the Green dragon on South's 3rd discard support this theory, but it's only a theory. Both of his east discards feel late, and leaves me wondering if he was holding that first one hoping for a pair, and Murphy decided to visit 6 tiles later.
Viewing the whole board, honors are a safe throw as well. East and all the dragons are nigh exhausted. The 1 and 3 of dots can say that low dots are a safe discard to west, but really, with two players showing bamboo as a safe discard, do that. (Muwahaha they fell right into my trap >D.)

In the end West had: Dragons open.
;;
Didn't know he had a hell wait on the 7 of dots for an open half flush, green dragon, dora 2; 5 han mangan.

Hmn, That's all I've got, If anyone has anything better to critique from these three hands, please add ^_^;.

[Rosti]

Also playing the mini game on Saki's website

I wouldn't try and infer anything strategically from that thing. In my experience it's biased up to give ridiculous hands, and the AI is pretty weird.

I'll add properly to discussion later, but just a point for now that what you can infer from discards is, and will always be, based on probability and therefore won't be perfect every time. A tile is almost never completely safe from ron unless it's already been discarded by them.
I just throw this out because I know a lot of people contest certain trains of thought when they learn strategy because they don't work all the time. For example, that tiles around the riichi discard are usually more dangerous, though it's far from 100% sure that they'll be waiting for a tile near the one they riichi'd on. This just being a point because quite often people will deal in and say "ah, I was wrong to discard that tile" when actually they weren't wrong, they were just unlucky that they happened to be waiting on it, when seven or eight times out of ten it would have been fairly safe. The game is all about statistics, and you will always get those people who don't discard a single sou tile all game, and end up waiting in tenpai on pin tiles and ron from you. It doesn't stop the fact that discarding a pin tile to avoid discarding a sou is the superior choice in that situation, if for no other reason that it's better to deal into a (most likely) small hand than the big single-suit one it otherwise could have been.

Basically I'm saying that if there are things you should be inferring from the discards, then don't draw conclusions from whether they were actually right or not. Just because they weren't waiting on what you thought they were doesn't mean your logic was necessarily wrong. It was just unlucky.

[Referee]

It's Saki's website, not Saki Portable. I don't know about the strategy level of the opponents, but I don't remember many big hands there (Haneman at most, except if I built them, I got a Koku Shimusou there, but not the opponents.

I understand that this reading discards thing is based on probabilities, I guess I would need to get it in small steps. For instance, I can't see if a hidden hand is going to be big or small. Sometimes, an opponent reaches, then I discard one of the tiles in his pool, and another opponent calls ron for a Mangan, while dealing into the first opponent would have been less painful.