Frequently asked questions (FAQ)

General questions:

[Narde]: Opponent has blocked 6 spots, however none of my checkers are in home board. How so?
[Backgammon]: Sometimes an opponent can “hit and run” to a safe position on the board. Why?
Opponents often double not allowing to finish the game. If I accept, I risk to lose more, if I refuse, then I lose the match. Is this fair?
My opponent is extremely lucky. Has he hacked the game?
Upon launching the game I am offered to buy a HD version. Why does this happen and what is this version for?
What do player name colors indicate in online game?
How can I change game interface language?
Why do my dice roll statistics differentiate from expected values?
Why do I sometimes get thrown out of the game during the match?
I won with gammon at base bet of 100 gold, but I received only 130 gold. Why?
How win/loss sum is being calculated?
Why do I often see a message “Awaiting opponent’s response”?
I was insulted by another player. What can be done about this?
What to do if I found a bug in the game?

Dice generator:

How are dice generated?
How does generator select the values?
I think that opponent is lucky and gets better dice than me. Why?
My dice statistics indicate that the value differs from mathematical expectancy. Is the algorithm wrong?
How to check if dice are being generated fairly?
Where can I view Random Number Generator source code?

Tournaments:

What are tournaments and what is their purpose?
What does the winner and runners up get as a reward?
In what backgammon style is the Tournament held?
What variations of Tournament are there?
When are the Tournaments hosted?
How to participate in a Tournament?
I have registered. What now?
Does the Tournament still start if the member list is not full?
The Tournament has started. What now?
What if I’m late?
How many tours are in the tournament and which ladder system is used in the tournaments?
I won!
I lost…
Tour started, but I still see the “Awaiting tour start” message. Why?
What things should all Tournament participants know?

Elo rating:

What is your Elo rating and how is it calculated?
What does my rating indicate?
What affects my rating?
What does not affect my rating?
How is the rating calculated?
Can you give an example?
What are Quitters?
How to see the rating of top 100 players?

Shop:

All the items I bought have disappeared. Why did this happen and how to return them?
I made an in-app purchase in the Shop, but did not get the item, despite having my money withdrawn. What to do?
I bought in game gold in the Shop, money was withdrawn, but I did not get the gold. What to do?
I bought a set of boards. How do I change the board?
Why do I see no items in the Shop?
I purchased the “No ads” package, but the ads are still there.

General questions:

Q: [Narde]: Opponent has blocked 6 spots, however none of my checkers are in home board. How so?
A: According to the standard rules 6 spot block is allowed if before the block there is at least 1 opponent’s checker.
Note: there is a rule variation in which 6 checker block is allowed only if 1 opponent’s checker is in home board. However, in regular rules there are no such limitations.

Q: [Backgammon]: Sometimes an opponent can “hit and run” to a safe position on the board. Why?
A: Yes, it is allowed to “hit and run”. If you hit an opponent’s checker you can move it to a safe spot on your checkers.
Note: there are different backgammon rule variations which do not allow to “hit and run”. These rules are mostly used in Middle East, however in regular rules there are no such limitations. This is why you can “hit and run”.

Q: Opponents often double not allowing to finish the game. If I accept, I risk to lose more, if I refuse, then I lose the match. Is this fair?
A: Yes, it is fair. You can double at any time during the game before rolling dice. This backgammon rule is used all over the world.

Q: My opponent is extremely lucky. Has he hacked the game?
A: No, this is impossible. It is simple luck, you will soon get lucky as well. The dice are generated on the server and information is being sent in encrypted format.

Q: Upon launching the game I am offered to buy a HD version. Why does this happen and what is this version for?
A: It means that your device has a Retina display and can support the HD version of “Backgammon Masters” with better graphics. However, currently you have launched the regular version with regular graphics. This notification is purely for information. If you cancel it, nothing will happen.

Q: What do player name colors indicate in online game?
A: The color indicates player’s reputation. White color – neutral, red – negative, green – positive. Furthermore, moderators and administrators have a unique orange color.

Q: How can I change game interface language?
A: You can change language in game settings. Open the main menu, click on the round gear icon, then click on “Settings”. Scroll down to the last option and you will see the current language and ability to change it.

Q: Why do my dice roll statistics differentiate from expected values?
A: You have made too few rolls for statistics to be close to expected values. You have to make at least 2000 rolls.

Q: Why do I sometimes get thrown out of the game during the match?
A: Game stability depends on the quality of internet connection. We found out that players who play via 3G, GPRS are experiencing connectivity issues more often. We are constantly working on improving the stability of the game for devices with all types of connection.

Q: I won with gammon at base bet of 100 gold, but I received only 130 gold. Why?
A: It could mean that possible win sum (base bet * win coefficient) is higher than sum of gold your opponent holds. This means that the opponent does not have the necessary amount of coins, therefore the bet is limited by amount of coins your opponent holds. You can view the bet limit at the side panel during the match.

Q: How win/loss sum is being calculated?
A: Base bet is set at the beginning of each match. Depending on how many coins each player has, a bet limit is set. Bet limit – sum above which it is impossible to raise the bet. Usually this sum is equal to one player’s gold amount. Let’s illustrate this with an example. Base bet is 100 coins, first player has P1 = 200 coins, second player has P2 = 150 coins. The bet limit is equal to Lim = 150 coins. Second player won with gammon C = 2.
This is the calculation process:
1) Firstly, the game determines the current bet which depends only on the doubling cube. It can be equal to bet limit if players doubled several times. In our case the current bet at end of the match is equal to S = 100 gold, since the doubling cube was not used.
2) Determining the win coefficient (regular win – 1, gammon – 2, home gammon – 3, backgammon – 4).
Doubling the current bet with win coefficient. If the result is higher than bet limit, then it is lowered to bet limit. In the given example the second player had a gammon win, therefore the current bet is equal to SC = S * C = 100 * 2 = 200, however since it is above the bet limit, it is lowered to be equal to bet limit SK = Lim = 150 gold
3) Commission sum T is being deducted from the total sum of both player’s bets. In this case, T = SC * 2 * 0.05 = 15 gold
4) The winner gets W gold including commission, the losing player loses L gold. In this case, W = SC – T = 150 – 15 = 135 gold goes to the winner, the loser loses L = SK = 150 gold.

Q: Why do I often see a message “Awaiting opponent’s response”?
A: This message appears in cases where server loses connection with your opponent. It can indicate that your opponent has a bad internet connection. There are no problems on your side and the message is purely for information.

Q: I was insulted by another player. What can be done about this?
A: If a moderator is online, then refer to him for help. If not, please write to game support with name of the player, description of the incident and a screenshot. If you want to ignore this player in the game, you can add him to the black list.

Q: What to do if I found a bug in the game?
A: If you found a logical bug (game against the rules) or a graphical bug then contact support. Please indicate in your mail: when does the bug occur, what are the conditions and details about the bug itself. If you provide all this information we will be able to find and fix the bug quicker. Please indicate your e-mail as well, so we can reply to you.

Dice generator:

Q: How are dice generated?
A: For each roll “Backgammon Masters” generates two random values from 1 to 6 using a random number generator. For online game the random numbers are generated on the game server. At the beginning of the game the server creates a game room for both players with a unique ID. This unique ID acts as seed for random number generator. Since the seed is unique, the generated numbers will also be unique. This is why every match has a unique sequence of dice and it differs from match to match. During the match the server receives data from the unique sequence and in turns sends it to players. This is why no matter what happens on the board the sequence has already been created and known to server.

Note: in game against AI, hotseat, Bluetooth and GameCenter the random number generator operates on player’s device.

Q: How does generator select the values?
A: The generator selects values only based on the seed. Since the sequence is generated from seed at the beginning of each match, the sequence cannot change during the match. This is why no situation in game can affect the dice sequence.

Q: I think that opponent is lucky and gets better dice than me. Why?
A: Don’t worry, algorithm is completely random. If you are not lucky now, then you will be lucky later. In either case, you can check fairness of the algorithm by looking at the individual dice roll statistics.

Q: My dice statistics indicate that the value differs from mathematical expectancy. Is the algorithm wrong?
A: No, the algorithm is functioning correctly. You have made too few rolls. You have to make a couple of thousand of rolls for the values to be close to mathematical expectancy.

Q: How to check if dice are being generated fairly?
A: First of all, check individual statistics for your dice rolls. To see it click on the „View statistics” button in the main menu or in match results window.

You can also use .dices command in chat which will display average sum of all rolls on server since its restart.

Q: Where can I view Random Number Generator source code?
A: If you wish to view the source code of the RNG used in Backgammon Masters, you can download it here.
https://2kbgames.com/backgammon/random_source.zip

Tournaments:

Q: What are tournaments and what is their purpose?
A: A Tournament is a series of games in which a number of contestants compete and the one that prevails through to the final round and wins is declared the best for that competition. It is a good way for players to realise their potential and gain experience.

Q: What does the winner and runners up get as a reward?
A: The winner of the tournament gets respect and honor of the player community. The winners name is listed in the “Tournaments” section. Additionally, the winner gets 80% of the whole sum invested by all participants of the tournament. In future updates more rewards will be added such as cups and medals.

Prizes:
Participants: no more than 8
1st place – 60%
2nd place – 40%

Participants: 8 to 16
1st place – 50%
2nd place – 25%
3rd, 4th places – 12.5%

Participants: 16 to 32
1st place – 40%
2nd place – 20%
3rd, 4th places – 10%
5th to 8th place – 5%

Participants: 32 to 64:
1st place – 33%
2nd place – 16%
3rd, 4th place – 8.86%
5th to 8th place – 4.16%
9th to 16th place – 2.08%

Q: In what backgammon styles are the Tournaments held?
A: During the beta test phase the tournaments will be held only in two most popular game styles – backgammon and narde. It is possible that in the future tournaments will also be introduced for less popular styles such as tavla and nackgammon.

Q: What variations of Tournament are there?
A: The tournaments are separated in daily tournaments (maximum participant count of 32 or 64) and weekly tournaments (128 participants).

Q: When are the Tournaments hosted?
A: Currently tournaments are in stage of beta testing, therefore we don’t yet have a strict schedule for the tournament time. Currently it has been decided to hold tournaments at both 21.00 Moscow time and 21.00 by New York time. However, we would like to remind everyone that we are listening to all recommendations of the players regarding the optimal time for holding of tournaments.

Q: How to participate in a Tournament?
A: Click on the “Tournaments” section in game lobby. You will see all the previous and upcoming tournaments. Upcoming tournaments will be seen 6 hours before the beginning of the daily tournament and 1 day before the weekly tournament. Tournaments open for registration are indicated with a green button that says “Registration”.
After clicking the “Register” button it will change to “Cancel”. This means that you can cancel the registration submission and receive the participation fee back. However, once you cancel the registration submission, you will not be able to register at the particular tournament again.

Q: I have registered. What now?
A: Now you have to wait for the tournament to start. This does not mean that you have to spend all the time in the tournament lobby. You can quit the game and go on with your daily chores and then return to the lobby just before the tournament.

Q: Does the Tournament still start if the member list is not full?
A: The Tournament starts under condition that there is more than one participant.

Q: The Tournament has started. What now?
A: Once the tournament has started, you will see its status change. There will be an indication for “Waiting for tournament to start”. This status indicates that the tournament has begun and opponents are being assigned for the participants. This won’t take long and soon you will see a “Play” button. Click the button and confirm that you are ready. If the opponent isn’t late, the match will begin.

Q: What if I’m late?
A: If you are late, then the opponent gets a technical victory and you get a technical loss. This means that the tournament is over for you.

Q: How many tours are in the tournament and which ladder system is used in the tournaments?
A: The tour count depends on how many participants have applied. The tournaments follow this system: you win – you proceed to the next tour, you lose – the tournament ends for you.

Q: I won!
A: If it was not the final match, then after you have won you have to return to “Tournaments” section of the lobby. You will see text “Awaiting for tour to start”. After all players finish their matches, the new tour will begin. If you won the final match, then you will hear sound of coins being deposited and a notice will appear congratulating you.

Q: I lost…
A: Unfortunately, the tournament ends for you. Don’t worry, you will be able to try again the next day!

Q: Tour started, but I still see the “Awaiting tour start” message. Why?
A: Not all players get an opponent. An odd number of players can register for the tournament. If this happens, then one participant does not get an opponent. This is why he gets a technical victory and proceeds to the next tour. This can also happen in the following tours if the number of participants is an odd number.

This means that you proceed to the next stage without playing a match.

Q: What things should all Tournament participants know?
A: First and foremost – you have to be in the lobby’s “Tournament” section from the beginning until the end of the tournament. You will have to click the “Play” button and always confirm that you are ready. We will later add more notifications for the players during the tournament.

Elo rating:

Q: What is your Elo rating and how is it calculated?
A: The Elo rating system is a method for calculating the relative skill levels of players in competitor-versus-competitor games such as Chess and Backgammon.
More information about Elo on Wikipedia.

Q: What does my rating indicate?
A: The rating compares your skill level with that of other players. You can determine your skill level using the following illustration.

Q: What affects my rating?
A: – Wins and losses. When you win, your Elo increases. When you lose, it decreases.
– Rounds in the Match. Winning a long match earns you more points than a short one. This is because in a long match, skill plays a bigger part than lucky dice rolls.
– Difference in ratings. Beating a player with a higher rating yields more points than beating a player with a lower rating.
– Amount of matches played. “Warm up” mode is enabled for new players with less than 500 experience points.

Q: What does not affect my rating?
A: – Number of wins and losses during one match. It does not matter how many rounds you won or lost. If you ended the winning match with score 13-12, then your rating will increase. It does not matter with what score you won the match, a win is a win.

Q: How is the rating calculated?
A: Rating is calculated by the following formula:
W = (1 – P) * M * S
L = P * M * S , where:
W – number by which the players rating changed as a result of a win
L – number by which players rating changed as a result of a loss
P – probability of the player winning the match. Probability is calculated by the following formula:
P = 1 / (1 + pow(10,(-D * sqrt(n) / 2000))) , where:
pow – 10 to the power of …
D – rating difference between two players. This is calculated for every player seperately. One player will have a positive D (indicating that the player has a higher rating than the opponent), the other player – a negative. For example, D for first player is calculated in the following manner:
D1 = R1 – R2 , where R1 – first players Elo rating, R2 – second players Elo rating
N – match length, i.e. up to how many points the game lasts in the match.
M – “boost” modifier for rating change. This is required for new players to quickly acquire rating which corresponds to their skill level. “Boost” modifier formula is the following:
M = (500 – E)/100 , if E is less than 400
M = 1 , if E is more than 400 , where E – players experience.
Experience (e) is the sum of length of all previous matches. For example, if the player has played 5 matches with 3 points in each, then the experience is 15.
This way experience is used when calculating the “boost” modifier. The less experience, the bigger the “boost” modifier and the quicker Elo score will change. Once experience goes over 400 the “boost” modifier is set to 1 and Elo rating changes normally.
S – number of rating points at stake during the match. This is a basic parameter, indicating how many points a player will gain upon winning or losing.
S = 4 * sqrt(n) , where N – the length of the match, sqrt – square root
This parameter directly affects the amount of points gained upon a win or loss.

Q: Can you give an example?
A: Imagine a game between “Player A” and “Player B”. “Player A” has Elo of 1100, “Player B” has an Elo rating of 1500. “Player A” has 675 experience points and “Player B” has 950. “Player B” is more experienced, however “Player A” won the match. Match was until 3 points. Let’s calculate what “Player A” gets as the result of a win and how many points “Player B” loses.
The Elo difference is the following: D1 = 1100 – 1500 = -400, D2 = 400
Let’s calculate probability of win for first and second players accordingly:
P1 = 0.31 P2 = 0.69
Let’s calculate number of rating points at stake:
S = 4 * sqrt(3) = 6.92
“Boost” modifier for both players is equal to M = 1, since both players have more than 400 experience points.
Now you have all parameters required to calculate the final result.
Points gained by “Player A” are equal to:
W = (1 – P) * M * S = (1 – 0.31) * 1 * 6.92 = 4.77
Points lost by “Player B” are equal to:
L = P * M * S = 0.69 * 6.92 = 4.77. If “Player B” won, he would get W = 2.14, since he is a more experienced player comparing to “Player A” and his Elo rating is much higher.
This way, to get more Elo points, a player has to beat players of equal or higher Elo rating. Playing against players of a lower rating will not add many points to your Elo.

Q: What are Quitters?
A: “Quitters” are players who leave the game before an obvious loss or upon a high chance of getting a gammon loss. In order to timely escape a gammon, the player leaves the match. To avoid similar cases we have created a special algorithm which calculates the chance of gammon upon quitting. Naturally, gammon cannot be guaranteed, however if such a chance persists, then the player who stays will get two points instead of one.

Q: How to see the rating of top 100 players?
A: Click on “Online” Game, then log in to your Account. Click on the green “Statistics View” button, then click on the “Ratings” button. The header will indicate your place in the overall Elo rating and your Elo score.

Shop:

Q: All the items I bought have disappeared. Why did this happen and how to return them?
A: If you entered the game and noticed that your bought items have disappeared (boards, “no ads package”, “online package”) then you can restore them. Open “Shop” in game and click the “Restore” button. All bought items will be restored under condition that you used the same online game account to purchase them.

Q: I made an in-app purchase in the Shop, but did not get the item, despite having my money withdrawn. What to do?
A: Click on the “Restore” button in the Shop and all bought items will be restored. This works only when the purchase was completed.

Q: I bought in game gold in the Shop, money was withdrawn, but I did not get the gold. What to do?
A: In this case you have to refer to tech support and indicate the following information: your nick name, time when you made the purchase and which gold pack did you want to buy. This information is required to quickly find the transaction.
Contact tech support

Q: I bought a set of boards. How do I change the board?
A: Game boards can be changed during the game. Enter the in-game menu by clicking the pop up button at the top of the screen. You will be able to change boards at the bottom of the menu. Afterwards, click “Continue” to continue playing.

Q: Why do I see no items in the Shop?
A: If you open the Shop and see text “No loaded items”, then this might indicate that there is a problem connecting to server. Check your internet connection. If your internet connection is ok, then it means server is undergoing technical maintenance and you will need to wait for a little.

Q: I purchased the “No ads” package, but the ads are still there.
A: If you had money withdrawn for this service, then it means that purchase was successful. First of all, check the button for “No ads” package in the Shop. If the button says “Buy”, then click the “Restore” button. If the button has not changed to “Installed”, click the “Buy” button again. Important: if the purchase on server was successful, then you will not have to pay twice. But this is only in the case if you use the same account that you used when buying the package the first time.