Matagi suji: Difference between revisions

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==Theory==
==Theory==
Matagi suji relies on the power of a shape like "233" or "334". When a player has a "233", it is unlikely for them to discard a 3 early - turning "233" -> "23" - since it'd come at a loss of [[tile efficiency]]. So if a 3 is discarded early, it is less likely for them to have "23" (which waits on 1-4) or "34" (which waits on 2-5) remaining. As the 1-4 wait and 2-5 wait are less likely, an early discarded 3 makes 1-4 and 2-5 safer. Note: tiles towards the outside of a discarded tile are ''much'' safer. Tiles towards the inside are not much safer than a regular tile.
Matagi suji relies on the power of a shape like "233" or "334". When a player has a "233", it is unlikely for them to discard a 3 early - turning "233" -> "23" - since it'd come at a loss of [[tile efficiency]]. So if a 3 is discarded early, it is less likely for them to have "23" (which waits on 1-4) or "34" (which waits on 2-5) remaining. As the 1-4 wait and 2-5 wait are less likely, an early discarded 3 makes 1-4 and 2-5 safer. Note: tiles towards the outside of a discarded tile are ''much'' safer; tiles towards the inside are not much safer than a regular tile.


Conversely, it is more likely for a player to keep shapes like "233" until [[tenpai]]. So if a 3 is discarded early, it is more likely for them to have a "23" or "34" remaining. This means an early discarded 3 makes 1-4 and 2-5 more dangerous.
Conversely, it is more likely for a player to keep shapes like "233" until [[tenpai]]. So if a 3 is discarded early, it is more likely for them to have a "23" or "34" remaining. This means an early discarded 3 makes 1-4 and 2-5 more dangerous.
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==External links==
==External links==
* [https://pathofhouou.blogspot.com/2020/08/analysis-ura-suji-and-matagi-suji.html Matagi suji data analysis]] on Path of Houou
* [https://pathofhouou.blogspot.com/2020/08/analysis-ura-suji-and-matagi-suji.html Matagi suji danger analysis] on Path of Houou
* [https://www.mahjonggem.com/blog/2019/6/12/matagi-suji Matagi suji] on Mahjong Gem
* [https://www.mahjonggem.com/blog/2019/6/12/matagi-suji Matagi suji] on Mahjong Gem

Revision as of 16:13, 14 August 2024

Matagi suji, or "straddle suji", is a form of discard reading. It states that, when a number tile is discarded early, nearby tiles become safer. But, when a number tile is discarded late (especially if the riichi declaration tile), nearby tiles become more dangerous.

  • When a tile numbered 3-7 is discarded, the tiles within +/- 2 of that tile are affected by matagi suji.
  • When a tile numbered 2 or 8 is discarded, the 1-4 or 6-9 tiles are affected by matagi suji.

Table

Discard Remaining in Hand Matagi suji
2 23 1-4
3 23 or 34 1-4, 2-5
4 34 or 45 2-5, 3-6
5 45 or 56 3-6, 4-7
6 56 or 67 4-7, 5-8
7 67 or 78 5-8, 6-9
8 78 6-9

Theory

Matagi suji relies on the power of a shape like "233" or "334". When a player has a "233", it is unlikely for them to discard a 3 early - turning "233" -> "23" - since it'd come at a loss of tile efficiency. So if a 3 is discarded early, it is less likely for them to have "23" (which waits on 1-4) or "34" (which waits on 2-5) remaining. As the 1-4 wait and 2-5 wait are less likely, an early discarded 3 makes 1-4 and 2-5 safer. Note: tiles towards the outside of a discarded tile are much safer; tiles towards the inside are not much safer than a regular tile.

Conversely, it is more likely for a player to keep shapes like "233" until tenpai. So if a 3 is discarded early, it is more likely for them to have a "23" or "34" remaining. This means an early discarded 3 makes 1-4 and 2-5 more dangerous.

Effectiveness

"Tiles nearby the riichi declaration tile" are more dangerous. When folding, there usually isn't a need to consider matagi suji. A 4 discarded as a riichi declaration does make the 5 more dangerous, but a non-suji 5 is already very dangerous. However, it can make an impact when deciding whether to push or fold to begin with.

"Tiles outside of early discards" are relatively safe; about as safe as suji (but a bit less safe than suji).

External links