Alexander20
Alexander20
  • Threads: 2
  • Posts: 11
Joined: Oct 2, 2020
December 13th, 2020 at 3:44:25 PM permalink
Hi all.
I have a null 3x3 matrix (9 squares). The probability for a symbol x to be shown on each square is 0.2 and it is the same for all squares.The game plays one round at a time. If a symbol x appears on a square stays on it and the game runs one more round.

Is there a formula to calculate the probability of symbol x at round n (1<=n<=9)?
Wizard
Administrator
Wizard
  • Threads: 1518
  • Posts: 27044
Joined: Oct 14, 2009
December 13th, 2020 at 5:18:59 PM permalink
Are you asking, "What is the probability of at least one X on the board after n rounds?"
"For with much wisdom comes much sorrow." -- Ecclesiastes 1:18 (NIV)
ThatDonGuy
ThatDonGuy
  • Threads: 122
  • Posts: 6680
Joined: Jun 22, 2011
December 13th, 2020 at 7:00:37 PM permalink
Questions:

1. In each round, does each square without an x have a 0.2 probability of showing an x in that round?

2. Does the game end if there is a round where no new x's are created?
USpapergames
USpapergames
  • Threads: 18
  • Posts: 807
Joined: Jun 23, 2020
December 13th, 2020 at 8:26:09 PM permalink
Quote: Alexander20

Hi all.
I have a null 3x3 matrix (9 squares). The probability for a symbol x to be shown on each square is 0.2 and it is the same for all squares.The game plays one round at a time. If a symbol x appears on a square stays on it and the game runs one more round.

Is there a formula to calculate the probability of symbol x at round n (1<=n<=9)?



Omg, 😱 you're trying to solve the probabilities for Royal Slots :/

P.S. The payouts on the demo in no way reflect the probabilities of the payouts! I purposefully choose figures so far from the actual probabilities just to through of the mathematicians here, so I could see I you confused as the payout values I chose ;)
Math is the only true form of knowledge
CrystalMath
CrystalMath
  • Threads: 8
  • Posts: 1911
Joined: May 10, 2011
December 13th, 2020 at 8:31:50 PM permalink
Quote: USpapergames

Omg, 😱 you're trying to solve the probabilities for Royal Slots :/

P.S. The payouts on the demo in no way reflect the probabilities of the payouts! I purposefully choose figures so far from the actual probabilities just to through of the mathematicians here, so I could see I you confused as the payout values I chose ;)



Trolling much?
I heart Crystal Math.
USpapergames
USpapergames
  • Threads: 18
  • Posts: 807
Joined: Jun 23, 2020
December 13th, 2020 at 8:33:38 PM permalink
Quote: CrystalMath

Trolling much?



How is a skin a legitimate question trolling? If he's talking about my game I want to know about it! Honestly Crystal Math, I'm starting to think you're trolling me!
Math is the only true form of knowledge
Alexander20
Alexander20
  • Threads: 2
  • Posts: 11
Joined: Oct 2, 2020
December 14th, 2020 at 1:16:22 AM permalink
I am looking for the probability of a symbol X to be shown in any square at n round.

At round 1 probability is 0.2

At round 2 probability is (1-0.8^8) * (0.8 * 0.2) = 0.8322 * 0.16 = 0.1331

I can' t find a formula for the rest rounds.
Alexander20
Alexander20
  • Threads: 2
  • Posts: 11
Joined: Oct 2, 2020
December 14th, 2020 at 1:24:57 AM permalink
Quote: ThatDonGuy

Questions:

1. In each round, does each square without an x have a 0.2 probability of showing an x in that round?

2. Does the game end if there is a round where no new x's are created?



Yes
Alexander20
Alexander20
  • Threads: 2
  • Posts: 11
Joined: Oct 2, 2020
December 14th, 2020 at 1:52:11 AM permalink
Quote: USpapergames

Omg, 😱 you're trying to solve the probabilities for Royal Slots :/

P.S. The payouts on the demo in no way reflect the probabilities of the payouts! I purposefully choose figures so far from the actual probabilities just to through of the mathematicians here, so I could see I you confused as the payout values I chose ;)



I do not know your Slots. This mini game could be considered as a simplified version of Hold n Spin feature which is well known for several years in gaming industry. I am trying to figure out the math behind this feature and it is all about personal amusement and not commercial use.
rsactuary
rsactuary
  • Threads: 29
  • Posts: 2315
Joined: Sep 6, 2014
Thanked by
CrystalMath
December 14th, 2020 at 6:19:34 AM permalink
Quote: Alexander20

I do not know your Slots. This mini game could be considered as a simplified version of Hold n Spin feature which is well known for several years in gaming industry. I am trying to figure out the math behind this feature and it is all about personal amusement and not commercial use.



I have figured out the math behind the hold and spin feature. It's extremely complicated. Not sure I'm willing to just post openly about my results.

You don't specify, but if the intent is that you get three spins to hit an x before the game is over (and if you do hit an x, you reset to three spins), then the probability under your scenario of filling the screen is 0.3519481466.
Last edited by: rsactuary on Dec 14, 2020
Alexander20
Alexander20
  • Threads: 2
  • Posts: 11
Joined: Oct 2, 2020
December 14th, 2020 at 9:16:01 AM permalink
Quote: rsactuary

I have figured out the math behind the hold and spin feature. It's extremely complicated. Not sure I'm willing to just post openly about my results.

You don't specify, but if the intent is that you get three spins to hit an x before the game is over (and if you do hit an x, you reset to three spins), then the probability under your scenario of filling the screen is 0.3519481466.



Thanks for your response. I am trying to figure out this feature for quite long time. I can understand why you are not willing to share your knowledge openly. If you would like to give some hints/help via private message it would be great.
Ace2
Ace2
  • Threads: 32
  • Posts: 2706
Joined: Oct 2, 2017
December 14th, 2020 at 2:20:56 PM permalink
Quote: Alexander20

I am looking for the probability of a symbol X to be shown in any square at n round.

At round 1 probability is 0.2

At round 2 probability is (1-0.8^8) * (0.8 * 0.2) = 0.8322 * 0.16 = 0.1331

I can' t find a formula for the rest rounds.

I still can’t figure out what you’re asking. How can the probability of at least one X be LESS after 2 rounds (0.1331)than after 1 round (0.2) ?
It’s all about making that GTA
Alexander20
Alexander20
  • Threads: 2
  • Posts: 11
Joined: Oct 2, 2020
December 14th, 2020 at 2:43:01 PM permalink
Quote: Ace2

I still can’t figure out what you’re asking. How can the probability of at least one X be LESS after 2 rounds (0.1331)than after 1 round (0.2) ?



If symbol X appears in a square at the first round then and only then I proceed to the second round. At the second round, I already have one symbol X and I am looking for another symbol X to run the third round. This probability of the second symbol X is 0.1331 according to my calculations. At the third round, I have two symbols X and I want to calculate the probability to win another symbol X in order to proceed to the fourth round, etc.
Mental
Mental
  • Threads: 16
  • Posts: 1549
Joined: Dec 10, 2018
December 24th, 2020 at 2:35:45 PM permalink
Quote: Alexander20

If symbol X appears in a square at the first round then and only then I proceed to the second round. At the second round, I already have one symbol X and I am looking for another symbol X to run the third round. This probability of the second symbol X is 0.1331 according to my calculations. At the third round, I have two symbols X and I want to calculate the probability to win another symbol X in order to proceed to the fourth round, etc.



If I understand the rules, the game terminates on the first round where you do not get an X in an empty square. Therefore, the game could end on round 1 by filling all squares, but must end by round 9. Is that right?

The binomial distribution function of any spreadsheet will solve the problem. I don't want to do the work for you. I think you will learn more by attacking it yourself.

https://wiki.openoffice.org/wiki/Documentation/How_Tos/Calc:_BINOMDIST_function

Hint: If you get two Xs on the first round, you have to solve the same original problem with seven squares.
Gambling is a math contest where the score is tracked in dollars. Try not to get a negative score.
p13man
p13man
  • Threads: 4
  • Posts: 32
Joined: Jul 14, 2019
February 11th, 2021 at 10:18:14 PM permalink
The odds of being awarded a hold & spin feature in a base game is about 130/1. This is actually a quite useful thing to know because a lot of players 'play' for the feature. At $10 a spin, you're going to be spending $1,300 (on average over the long term) to get a single feature. So you're going to be disappointed when the feature only pays 3x or even 10x of wager, which it often does.
  • Jump to: