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Strange Creatures I


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10 replies to this topic

#1 araver

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Posted 19 January 2013 - 02:40 PM

During a cloudy night, on a far away distant barren planet in a far way galaxy, five creatures of five different species meet in a clearing near a lake. The planet is barren and hostile enough for all of them to survive better as a group. Four of them are herbivores, one of them is carnivorous (however it is not obvious which is which). A certain gas in the composition of the atmosphere makes all creatures develop only short-term memories and carnivorous creatures have developed to mimic their herbivore counterparts, so no herbivore species is able to recognize a carnivorous creature as being carnivorous until something (a scent, a sound, a series of movements) triggers an ancenstral memory. They are however sufficiently developed as species to follow (some form) of logical reasoning.
 
Each night, the carnivore may strike deadly to eat one of the herbivores. Each night, the herbivore's instinct makes them investigate (exactly one) element in their surroundings to discover a threat. Unfortunately they don't know what type they are, as they posess no long-term memory (more than 5 days).
 
* One of the species is notorious for being fearful of everything. We'll call them PARANOIDS because after they investigate another animal (even one of the same species) their brains marks the target as a carnivore threat (even if it is herbivore).
* The second species is notorious for being too trustful. We'll call them NAIVE because all their investigations lead to them trusting the targeted creature
* The third species is confused, to say the least, INSANE to be more precise. They always trust carnivores upon inspection and distrust herbivores (for no apparent reason).
* The fourth species is SANE. Their advanced senses make their results spot on. Always.
 
Each day, they can all share their results and discuss. Each day, all alive creatures must cast a vote for one of them to be sacrificed as a possible threat to the group. Votes can be changed once they are cast. If one of them reaches plurality (largest number of votes from total number of possible votes, not necessarily a majority of votes) at the end of the day he is sacrificed by the others and all will learn if they've sacrificed a herbivore or a carnivore before a new night begins.
 
1) Prove (or disprove) that there is a strategy that can be agreed beforehand (during first night) so that the herbivores win (win = no carnivore is alive in the group). 
2) Prove (or disprove) that there is a strategy that can be agreed beforehand (during first night) so that the herbivores win if abstaining is allowed. 
3) Prove (or disprove) that there is a strategy that can be agreed beforehand (during first night) so that the herbivores win if changing of votes is NOT allowed. 
 
Or in a simpler setting:
Spoiler for ...

Edited by araver, 19 January 2013 - 02:46 PM.

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Summer of 2013:
Show the Mafia world you're back in action ... signup for The Coup of Rhotus Mafia.You know you want it, we know you still have it in you so .... Come join the madness!  :thumbsup: 
 
Puzzles open: Strange Creatures I Past puzzles: Mystery Operation Series: I, II, III, IV; Contamination Scenario;
Past games: Crack the Code Series: III, VII, IXPast mafia games: UN Mafia, UN Mafia II, Star Trek Mafia, TMM IV

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>> Not only is the universe stranger than we imagine, it is stranger than we can imagine.


#2 Molly Mae

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Posted 19 January 2013 - 07:14 PM

Nice to see you back in these parts, Araver.  I have some observations from playing the game, but certainly no proof (or disproof) as to a perfect strategy.  I think it largely depends on when the carnivore shares information.

 

EDIT: Prematurely hit submit.  I'll wait to see what comes up.  


Edited by Molly Mae, 19 January 2013 - 07:15 PM.

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A recipe for honey-pickled apples


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Spoiler for Molly's Rules to Live By

#3 k-man

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Posted 23 January 2013 - 03:55 PM

Hi Araver! Nice to see you again.

 

Can you clarify the sequence of events? I assume they agree on the strategy first, then they inspect each other, then a carnivore strikes and kills one herbivore. Then, when the day comes, with only 3 herbivores left they have only one chance of identifying a carnivore or they lose. Is this right?


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#4 CaptainEd

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Posted 23 January 2013 - 04:11 PM

For that matter, does the carnivore get to take part in the deliberations--the decision on the proper strategy?


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#5 araver

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Posted 25 January 2013 - 10:21 PM

Hi Araver! Nice to see you again.
 
Can you clarify the sequence of events? I assume they agree on the strategy first, then they inspect each other, then a carnivore strikes and kills one herbivore. Then, when the day comes, with only 3 herbivores left they have only one chance of identifying a carnivore or they lose. Is this right?


Hi! Indeed LTNS.

To clarify the sequence of events, abbreviating Day/Night, the following timeline is assumed strict:
during N1 - They can discuss / agree on strategy
end of N1 - Each herbivore can inspect one other and receive 1 result (according to it's species type)
end of N1 - carnivore strikes a chosen secret target, 1 herbivore dies
beginning of D1 - 3 herbivores and 1 carnivore left
during D1 - They can discuss and each of them (including the carnivore) get a vote which they MUST (or in case of (2) CAN) use on the other alive creatures.
end of D1 - If a plurality is reached, that creature is "sacrificed"

The rest of the timeline repeats itself, N2 follows, then D2, etc.with the same night/day events.

However I cannot answer your question other than using spoilers:

Spoiler for

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Summer of 2013:
Show the Mafia world you're back in action ... signup for The Coup of Rhotus Mafia.You know you want it, we know you still have it in you so .... Come join the madness!  :thumbsup: 
 
Puzzles open: Strange Creatures I Past puzzles: Mystery Operation Series: I, II, III, IV; Contamination Scenario;
Past games: Crack the Code Series: III, VII, IXPast mafia games: UN Mafia, UN Mafia II, Star Trek Mafia, TMM IV

Almost random quotes:
>> Not only is the universe stranger than we imagine, it is stranger than we can imagine.


#6 araver

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Posted 25 January 2013 - 10:24 PM

For that matter, does the carnivore get to take part in the deliberations--the decision on the proper strategy?

 

Indeed it does.

 

For all they know, all the other creatures look like herbivores so there is no point in trusting or not trusting any input in the deliberations.  

 

P.S. Don't ask me how they know there is exactly one carnivore around. The backstory doesn't explain it. so take it as a more abstract MacGuffin ;)


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Summer of 2013:
Show the Mafia world you're back in action ... signup for The Coup of Rhotus Mafia.You know you want it, we know you still have it in you so .... Come join the madness!  :thumbsup: 
 
Puzzles open: Strange Creatures I Past puzzles: Mystery Operation Series: I, II, III, IV; Contamination Scenario;
Past games: Crack the Code Series: III, VII, IXPast mafia games: UN Mafia, UN Mafia II, Star Trek Mafia, TMM IV

Almost random quotes:
>> Not only is the universe stranger than we imagine, it is stranger than we can imagine.


#7 araver

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Posted 25 January 2013 - 10:30 PM

Nice to see you back in these parts, Araver.  I have some observations from playing the game, but certainly no proof (or disproof) as to a perfect strategy.  I think it largely depends on when the carnivore shares information.

 

EDIT: Prematurely hit submit.  I'll wait to see what comes up.  

 

Nice to see you too :)

 

This 3-part puzzle is unlike the game in at least 3 ways (one of which may or may not be a red-herring).

But for the purposes of this puzzle (optimal adaptive strategy), one may assume the worst-case, in which the carnivore has ample time to prepare and share any kind of information. So if the strategy has a weak point, assume the adversary (carnivore) always finds it (and has time to find it).


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Summer of 2013:
Show the Mafia world you're back in action ... signup for The Coup of Rhotus Mafia.You know you want it, we know you still have it in you so .... Come join the madness!  :thumbsup: 
 
Puzzles open: Strange Creatures I Past puzzles: Mystery Operation Series: I, II, III, IV; Contamination Scenario;
Past games: Crack the Code Series: III, VII, IXPast mafia games: UN Mafia, UN Mafia II, Star Trek Mafia, TMM IV

Almost random quotes:
>> Not only is the universe stranger than we imagine, it is stranger than we can imagine.


#8 k-man

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Posted 25 January 2013 - 10:45 PM

However I cannot answer your question other than using spoilers:

Spoiler for

 

Not sure why you had to use a spoiler, as I find it very obvious (unless I'm missing something obvious :huh:), but out of respect to you I will use spoiler too

Spoiler for

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#9 araver

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Posted 25 January 2013 - 11:41 PM

However I cannot answer your question other than using spoilers:

Spoiler for

 

Not sure why you had to use a spoiler, as I find it very obvious (unless I'm missing something obvious :huh:), but out of respect to you I will use spoiler too

Spoiler for

Let me rephrase it:

Spoiler for

  • 0

Summer of 2013:
Show the Mafia world you're back in action ... signup for The Coup of Rhotus Mafia.You know you want it, we know you still have it in you so .... Come join the madness!  :thumbsup: 
 
Puzzles open: Strange Creatures I Past puzzles: Mystery Operation Series: I, II, III, IV; Contamination Scenario;
Past games: Crack the Code Series: III, VII, IXPast mafia games: UN Mafia, UN Mafia II, Star Trek Mafia, TMM IV

Almost random quotes:
>> Not only is the universe stranger than we imagine, it is stranger than we can imagine.


#10 Molly Mae

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Posted 28 January 2013 - 10:47 PM

Spoiler for Observations

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A recipe for honey-pickled apples


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Spoiler for Molly's Rules to Live By




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