mj_Help Features

B.1 Offensive Help

Offensive help includes hand hints and the tile status display.

The “Hint” or “H” button shows a recommended “goal” hand in the bottom row (Figure B1).  These 14 “goal” tiles should not be confused with the 13 or 14 tiles in the player’s hand.  Table Type “Table 1” does not have the extra row to show the goal hand, but can show the goal hand and actual hand together.  This is done by white (open), yellow (need a joker), or red (closed) shading over missing goal tiles to distinguish them from your current tiles (Figure B2).  On the other Table Type, when sorted by a specific hand, tiles matching a goal hand are shown above it and any remaining unmatched tiles are shown at the top right.  In Table Type “Table 2”, the top two rows show the player’s tiles and the bottom row shows the recommended goal hand.

It is recommended to resist using the “Hint,” “Best Hands,” “Best Groups,” “Ranks,” and “Auto Hold” features and decide yourself what hand to make and which tiles to pass or call.  This develops the skills needed to play without help.  However, the game can be played much faster when using the automated aids.  These aids can also help you learn by comparing what you would do with what the computer would do.

Figure B1.  Sorting by Recommended Hand – Tiles are sorted against a Recommended “Goal” Hand shown in the bottom row when “Hint” or “H” is pressed, Table Type “Table 2”

The same recommended hand and sorted tiles are shown for Table Type “Table 1” in Figure B2.  This shows the same information in a more compact form.  The recommended-hand tiles you have are shown unshaded at the bottom.  Tiles you don’t have and need are shaded in white for an open hand if the tile is still available and in yellow if it needs to be a joker.  Closed hand tiles are shaded in red.  In all Table Types, top row tiles to the right are those not used in the recommended hand.  Shown (or eXposed) tiles are on the left of the top row on a black background (none in Figure B2).

Figure B2.  Sorting by Recommended Hand – Same hand as Figure B1, Table Type “Table 1”

Up to 8 computer-recommended hands (goal hands or “Best Hands),” can be shown in a popup display, Figure B3.  These goal hands are shown below the top row of the player’s current tiles.  Text below each hand shows the group name, card line number, open(X) or closed(C), hand value, number of matching tiles you have, and current hand completion odds.  Hands are ordered from highest to lowest winning odds from top to bottom.  The option with the highest odds is shown on the rack bottom row when the “Hint” button is pressed.  There may be additional hands that have the same odds, but only one is shown as the hint.  The “Best Hands” popup display is selected by pressing the “B” key, pressing the “B” display button, or by selecting the “Best Hands” option from the Menu.  The popup is cleared by pressing the space key, clear button, or by pressing “B” again.  Only hands with odds greater than zero are shown.  Beginner players are shown up to 3 possible hands.  Intermediate, up to 5 hands, and Pro players are shown up to 8 possible hands. 

Any hands shown can be chosen as the sorting hand by clicking on the first tile on the left in the desired row.  A small F will be shown at the lower right.  This means the sorting/recommended hand is Fixed until you clear or select hint again.  You don’t need to select any of the computer-recommended hands and can choose your own hand to make at any time.

Figure B3.  “Best Hands” Popup Display

Figure B4 shows another popup display like “Best Hands” called “Best Groups.”  This display shows the current “best” hand of up to nine groups.  The groups are ordered by winning odds with highest odds at the top.  As in the “Best Hands” display, best is determined by the calculated odds of getting Mah Jongg before the tiles run out.  The odds usually start out low and increase (hopefully for you) as the game continues. Odds are shown in percent (%) chance from zero to 100.  “Best Groups” is accessed by the “G” key or by selecting it from the Menu.  It is unselected by pressing outside the popup, pressing “G” again or selecting “Clear.”  If a group has no hands with >0 odds, the group is not shown.

Figure B4.  “Best Groups” Popup Display Example

The Tile Status display is shown in Figure B5.

Figure B5. Tile Status Display

Tile Status Display: The tile status display shows statistics in columns for each tile type. A code for each tile type is listed in the far-left column.  The columns from left to right indicate, for each tile type, how many are:

Hand:           in your hand not shown/exposed

Shown:        shown by anyone

Discard:       discarded by anyone

Left:              left in the wall or in someone else’s hand

The columns labeled P# or P#C are the probability that you will have at least that number (#) of the tile before the tiles run out.  The probability shown is 1.0 if you have at least that number in your hand now.  The columns with “C” in them are closed-hand probabilities.

If you only need one tile, an asterisk will be shown next to any tiles you can call for Mah Jongg.

B.2 Defensive Help

  An example Defense Data display is shown in Figure B6 below.

Figure B6Defense Data Display

Defense is about knowing what tiles you should not discard (are most risky) and when you should not (and should) discard them.  Figure B6 above shows the raw defense data for each tile and player opponent.  This example is for East’s opponents and for the 2022 card at the beginning of a game.  The top left corner lists two tile types that are tagged with “LR:”, Least Risk, and “LRUn:”, Least Risk Unused.  The tiles in this example are “JO” or joker and “4C” or 4 crak.  The LR (Least Risk) is the overall (all your tiles) least risk tile to discard.  A joker is always low risk to discard because it cannot be called.  Jokers are often discarded near the end of a game after you decide there is more chance of losing than winning.  LRUn (Least Risk Unused) is the least risk tile that is currently unused in the hand you are making.

There are 3 pairs of columns labeled at the top with player position, “South”, “West”, and “North” in this example.  Each column shows the odds of a particular opponent needing the tile listed in the furthest left column.  Since this example is for the beginning of the game when no tiles have been called and exposed, the odds are the same for each player.

The numbers in parentheses after the opponent’s position name are the number of possible hands, card group(G=#), and card line number (L=#), if known based on tiles showing and discarded.  Because at the beginning of the game all hands are possible, the 932 number is the number of unique hands defined by the 2022 card.  The card group number will be zero unless there is only one group possible.  The card line number will be zero unless there is only one hand possible.  The groups (also called categories) for the 2022 card are:

  1. 2022
  2. 2468
  3. Any Like Numbers
  4. Quints
  5. Consecutive Run
  6. 13579
  7. Winds-Dragons
  8. 369
  9. Singles and Pairs

There are two columns shown for each opponent.  The first is the odds that the opponent has a particular tile in a hand they can make (not already exposed).  Odds of 100% means that they will use that tile type in a hand they can make and they might be able to call the tile.  Jokers always have zero call odds because they can never be called.  The other tile’s odds depend on tiles discarded so far and tiles exposed by each opponent.  Beginning odds when no tiles are yet called give the approximate odds of each tile type being used.  For the 2022 card, this is the percentage of the 932 unique hands that use each type tile in at least one set.  In the 2022 card, the flower tile has the highest starting use percentage of 32.3%.

The second column is the how many of each tile has been discarded so far by the listed opponent. 

This raw data display is not the only form of defensive help available.  There are two other types of defense help:

  1. Defensive Status Display – shows current level of defensive risk, both overall and, optionally, in 5 different areas
  2. Discard Selection Warning – indicates when a selected discard tile has significant known risk of being used by an opponent

An example of the Defensive Status Display is shown at the bottom of Figure B7 (above the “Done” button).

Figure B7. Example Display showing Defense Status (Table Type “Table 2”)

Figure B8Zoomed in on the Defensive Status Display Section

The status is shown based on the following 5 risk areas, each with three risk levels calculated (Green = Low, Yellow = Medium, Red = High):

  1. T = Time to get tiles needed for Mah Jongg is limited
  2. W= Probability of Winning is relatively low
  3. F = Few possible hands are left for opponent(s) (you may know what not to discard)
  4. D = Dangerous Discard tiles are in your hand (likely tiles to be used by an opponent)
  5. C = Close to Mah Jongg – opponent(s) showing many tiles are likely close to Mah Jongg.

The last numeric indicator (5.0 in this example) is an overall risk level quantified between 0 and 5 with 0 as lowest risk and 5 as highest risk.  In this example, T=Time needed is medium risk (yellow) because the number of tiles needed for Mah Jongg is getting too close to the expected number of turns left.  The Dangerous Discard area is high risk (red) because one of the tiles is likely to be needed by an opponent (West).  The overall risk is the scaled average of the individual risks with the scale factor depending on the defense help level setting.  The Defense help level also sets what defense status data is displayed.  A Defense help level of “Min” only shows a warning if a tile selected for discard is risky (described in the next paragraph).  This data is also only shown when the overall risk level is medium or high (yellow or red).  You should be more willing to break up your hand and try to force a wall game if the risk level is high (red).  Before you reach the medium risk level, a tile may still be risky to discard and it is up to you to decide.  The Defense Data display will show the odds that the tile can be used by your opponents.

Figures B7 and B8 above show an example with a tile selected for discard (7 bam) indicating a high risk of being used by an opponent (West in this case).  The high risk is indicated by a selection highlighted in red, rather than the normal blue.  If the risk level was medium, the selection highlight color would be yellow.  The 7 bam tile has a 60% chance of being needed by West.  This can be seen by the corresponding Defense Data display, Figure B9. This display also shows that West has 10 possible unique hands left that can be made.  Note that in this case, the odds of calling the 8 bam tile by West are shown and are zero because West has already exposed a set of three 8 bams and you can’t add to an exposed hand.  If the Flower tile were not being used and selected, it would also show a high risk due to a 61.9% chance of being needed by South.  When a goal hand is shown and used to sort your tiles, the discard warning is based only on the “Extra” tiles that are not being used (upper right of green rack).  In this case, it would let you select and discard the Flower without warning you, even though South probably needs it.  To get warnings for all the tiles, you need to stop showing the hint.

If the Dangerous Discard (D) status indicator/button is shown, the tiles that are least and most risky can be shown by pressing the “D” button/indicator.  Any medium or high-risk tiles will be highlighted in yellow or red.  The lowest risk tiles will be highlighted in green.  There are 2 shades of green, one is for the overall lowest risk tile and the other is for the lowest risk tile you are not using in a current goal hand.  Note that the lowest risk tiles can also be high risk, but will still be shown as green unless you select them.  If risky and selected, the green color will change to yellow or red.  If Auto Done is set and a risky tile is selected, the tile is not automatically discarded and Auto Done will be suspended until the Done button is selected.  Flowers are almost always risky for the 2022 and 2023 cards.

Notes on Defense Discard warnings:  Please note that even if there is a 100% chance that the discarded tile type is used by an opponent, this does not mean that they are able to call the tile or don’t already have all of that type tile they need.  The logic only uses information the real player has available:  what tiles have been discarded, exposed, and are in the primary player’s hand, along with knowledge of all the possible hands.  The actual tiles in the opponent’s hand are not used by the logic.  In many cases, the tile will be needed for a single or pair, but will only be able to be called if it is the last tile needed.  The defense logic does not know if it is the last tile needed (unless the player has 13 tiles exposed, which is highly unlikely and not possible on the 2022 card).  It is up to you to decide how much risk to take and which tiles to discard.

It is difficult to decide to break up your hand and give up on winning.  If possible, switch to a different hand that uses the tiles that are too risky to discard.  However, if the odds are high enough that you are going to lose, it is better to play defense and force a wall game to maximize your long-term score.  Beginning players need to learn offense first and focus on learning the rules and how to win.  Practicing defense comes later.  That is why the default Defense Help is “None” for skill type Beginner.  The default setting for Intermediate and Pro is “Avg.”  The default Defense Help level can be changed at the beginning of the game and stored, if desired.

Playing defense is particularly important if playing for money or playing in a tournament.  Tournaments may decrease your score if you give Mah Jongg to a player by discarding a tile you could have known they needed.  Others playing along with you will not be happy if you unnecessarily give Mah Jongg to a common opponent, causing them to also lose.

Figure B9. Defense Data Display Example for Discard Risk Warning