These rules represents modern Taiwanese Mah Jong, where the most prominent feature is one additional set that is needed in a winning hand. Thus each player is given 16, instead of 13 tiles in the dealt hand (dealer being given naturally one additional tile to start the deal). A winning hand must contain 5 sets of Chows/Pungs/Kongs and a pair.
Other features not normally seen in other Chinese versions of Mah Jong include a replenishing Dead Wall with 16 (instead of 14) tiles.
As for the pattern selection, the Taiwanese Mah Jong is fairly classical, though some patterns have been added and some removed because of the additional set (e.g., Nine Gates of Thirteen Orphans cannot be collected in 16-tile Mah Jong; on the other hand, a limit is paid for patterns like Five concealed triplets).
Unlike most of the modern Chinese versions (Chinese Official being the major exception) included in Four Winds, the Taiwanese rules do not normally use a settling table to determine the final score. Instead, scores for patterns are simply added up. The payment scheme is unique: if the winner goes out self-drawn, all losers pay the winner directly the amount of his final score, but if the winner goes out on a discard, discarder alone pays the amount of winner's final score (not for all losers but just for himself). As in all modern versions of Asian Mah Jong, normally only the winner is paid.
16-tile version of Mah Jong is played also in Philippines, often with more classically oriented rules using a point-double scoring system, where East receives and pays double, and losers pay each other according to the difference of their final scores.
Related topics:
Tiles
Preliminaries
Playing
Miscellaneous
Scoring
Payments