X Winners Block-based Betting Rule

[HackFisher]

I think in the rule, maybe, ticket lucky number could be replace by ticket transaction hash, so user do not need to care about it.

[HackFisher]

TICKET_SALE: total tickets sales in this block.

TICKET_AMOUNT: amount of ticket output, users must pay that for the ticket

TICKET_ODD: the odd of the ticket, user can specify this to influence the chance of winning and correspond payouts. 2 means 50% chance of winning and 2x payout.

TICKET_LUCKY_NUMBER: User specified lucky number, betting the winning result.

RANDOM_NUMBER: random number for this block.

X: Maximum of winners block are going to payout jackpots, Expect_Winners

E: house edge, e.g. 1%, will go to prize pool for risk handle….

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Chance of winning for the ticket = (Ticket_Amount * X) / (TICKET_SALE * TICKET_ODD)

Total_Jackpot for the winning ticket = ((1 - E) * Ticket_Odd * TICKET_SALE) / X

Winning condition for the ticket:

HASH(RANDOM_NUMBER+TICKET_LUCKY_NUMBER) % (TICKET_SALE/TICKET_AMOUNT)  <  ( X / TICKET_ODD)

OR

HASH(RANDOM_NUMBER+TICKET_LUCKY_NUMBER) % {TICKET_ODD * TICKET_SALE/ (TICKET_AMOUNT * X)} < 1

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Risk analysis:

Risk means there is no enough funds to payout.
There is possibility that the ticket sale is not enough for payout jackpots, this case must be handled by using pool, or dynamically adjust the payout jackpots. Pool seems to be better but with more challenge.

The range of TICKET_LUCKY_NUMBER will influence the risk, the smaller the risk will be larger for the case of too many winner will happen, so the winner number threshold should be large.

that is,   {TICKET_ODD * TICKET_SALE/ (TICKET_AMOUNT*X)} should be close to the Range of TICKET_LUCKY_NUMBER.

Large TICKET_ODD could increase risk, because the chance to paying extreme large will increase. so there should be a range to limit.

Product analysis:
I think the disadvantage is that, it is not user-friendly, user is hard to understand what lucky number is (actually similar to betting dice? Then how about just letting user to a dice number from 1 - 6 for the user interface? in this case, we need X to be large to reduce the risk), and how will it affect the winning condition. So, no fun and meaningless for user to specify that.
Advantage is easy to implement.

Refer:
https://bitsharestalk.org/index.php?topic=4164.msg52868#msg52868