Mahjong

Infodump on Riichi Mahjong strategy as I learn.

• Riichi Book One, a strategy guide by Daina Chiba.
• Tile efficiency trainer
• Yaku infographic
• Calling for yakuhai is often not worth it. A very common beginner (and even intermediate) mistake is to overvalue yakuhai. Many hands actually decrease in expected value if you call a yakuhai (since it is an exchange of one han for all of the potential han from a closed hand plus tanyao).
• The value of pairs is maximized when there are exactly 2 pairs in a hand.
• Calling Kan is generally a bad idea in most situations.
  • It opens your hand, and the dora revealed often will benefit other players more. Especially think twice if another player is in Riichi.
  • If you call a meld, you can’t use the tiles elsewhere in your hand. e.g. if you have 444456, that’s two melds if you don’t call Kan but only 1 if you do.
• When not to call Riichi.
  • You have a bad wait
  • You have a (significant) lead
  • You already have a high-scoring hand
  • You have many possibilities to improve your hand
• When defending, use the suji technique to evaluate which tiles are safer to discard.