【The Value Comparison of Two-Sided Sequences】
I. Symmetrical Two-Sided Sequences
Based on the symmetry of numbered tiles 1-9, we can divide the 6 groups of edge waits into three symmetrical pairs: 23 and 78, 34 and 67, and 45 and 56. We will compare these pairs in terms of tile acceptance opportunities, improvement potential, potential for sequential edge waits, and hand potential extension.
II. Tile Acceptance Opportunity (Efficiency Ranking: High to Low) (For gameplay accepting chows)
The efficiency of accepting tiles for a two-sided sequence is the opposite of the value of a single tile. The easier it is for others to discard a tile you need, the easier it is for you to chow it, resulting in higher acceptance efficiency. Therefore, sequences containing terminal tiles (1 or 9) are better than those containing 2 or 8, which are in turn better than sequences containing only middle tiles.
Edge Wait Acceptance Efficiency: 23=78 > 34=67=45 > 56.
III. Redundant Tile Acceptance on the Same "Tile Track"
Numbered tiles belong to three "tile tracks": 147, 258, and 369. When you have too many sequences and need to discard one, and there is redundant acceptance on the same track – for example, both the 23 sequence and the 56 sequence need the 4 tile – then discard the sequence that sacrifices only one tile acceptance opportunity.
• Following the principle that "1, 4, 7 are connected", if you have both 23 and 56, discard the 56 sequence.
• Following the principle that "3, 6, 9 are connected", if you have both 45 and 78, discard the 45 sequence.
• The efficiency of 34 and 67 is similar; either can be chosen.
Example:
When your hand is reduced to the scenario above, although the two-sided sequence 56 has a higher base value than the edge wait 46, the presence of the 23 sequence means that discarding the 5 tile only sacrifices acceptance of the 7 tile and avoids being stuck on the same track. Discarding the 56 sequence and keeping the 46 edge wait is actually the superior choice.
IV. Sequence Discard Extension (Deceptive Discarding)
Here are two examples using the same 34 sequence. How do you play it?
- If we hold 34 and 67, if we discard the 3 first and then the 4 later, will opponents guess we still hold 67?
- But if we discard the 4 first and then the 3 later, will they guess we have a pair of 1 tiles?
The difference between an expert and an amateur lies in whether you can correctly guess opponents' hands from these details, or if they can guess yours!
V. Sequence Discard Extension (Barrel Theory + Maximum Probability)
Example 1:
In this hand, the 556 set has the highest tile strength and is easiest to improve. However, after improvement, the waiting choice is between the pairs of 2/9 and the edge wait 3 – not ideal! The ideal wait is the two-sided sequence 56 waiting for 4 or 7. Therefore, discard the 5 tile to increase the improvement chances for the "weaker" sequence.
Example 2:
Both can wait on 1 or 4. However, the 3 bamboo is harder to pung, while the 2 circle is easier to pung. Therefore, discard the 3 bamboo sequence and keep the 2 circle sequence.
VI. Two-Sided Sequence Waiting (Gameplay Dependent)
You are in the waiting stage. How do you play this hand?
- Purely considering the number of winning tiles: Waiting on 1 or 4 (8 tiles) is better than waiting on the pair of 2 circles and the pair of green dragons (4 tiles). The two-sided wait is better.
- Some local rules: If chows are not allowed but pungs are, perhaps discarding the 2 circle to declare ready is not bad, especially if many 1 and 4 tiles have already been played.
- Some local rules have bonuses for "Golden Hook" (winning by a single tile after a pung): Then discarding the 2 circle allows you to potentially go for a high-value hand, even if you pung the green dragon and then try to win by a single tile.
- Honor tiles: In the late game, they might be held in hand, making winning difficult. But sometimes they are recklessly discarded. It often depends on your opponents – some keep honor tiles, others don't.
Mahjong rules vary greatly by region. Different game flows and the discard pool will influence the outcome. We invite you to consider: according to the rules you play with, what would you discard?
