The Nonlinear Library LW - D&D.Sci: The Mad Tyrant's Pet Turtles [Evaluation and Ruleset] by abstractapplic
Apr 10, 2024
07:22
Welcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: D&D.Sci: The Mad Tyrant's Pet Turtles [Evaluation and Ruleset], published by abstractapplic on April 10, 2024 on LessWrong.
This is a followup to the D&D.Sci post I made ten days ago; if you haven't already read it, you should do so now before spoiling yourself.
Here is the web interactive I built to let you evaluate your solution; below is an explanation of the rules used to generate the dataset (my full generation code is available here, in case you're curious about details I omitted). You'll probably want to test your answer before reading any further.
Ruleset
Turtle Types
There are three types of turtle present in the swamp: normal turtles, clone turtles, and vampire turtles.
Clone turtles are magically-constructed beasts who are mostly identical. They always have six shell segments, bizarrely consistent physiology, and a weight of exactly 20.4lb. Harold is a clone turtle.
Vampire turtles can be identified by their gray skin and fangs. They're mostly like regular turtles, but their flesh no longer obeys gravity, which has some important implications for your modelling exercise. Flint is a vampire turtle.
Turtle characteristics
Age
Most of the other factors are based on the hidden variable Age. The Age distribution is based on turtles having an Age/200 chance of dying every year. Additionally, turtles under the age of 20 are prevented from leaving their homes until maturity, meaning they will be absent from both your records and the Tyrant's menagerie.
Wrinkles
Every non-clone turtle has an [Age]% chance of getting a new wrinkle each year.
Scars
Every non-clone turtle has a 10% chance of getting a new scar each year.
Shell Segments
A non-clone turtle is born with 7 shell segments; each year, they have a 1 in [current number of shell segments] chance of getting a new one.
Color
Turtles are born green; they turn grayish-green at some point between the ages of 23 and 34, then turn greenish-gray at some point between the ages of 35 and 46.
Miscellaneous Abnormalities
About half of turtles sneak into the high-magic parts of the swamp at least once during their adolescence. This mutates them, producing min(1d8, 1d10, 1d10, 1d12) Miscellanous Abnormalities.
This factor is uncorrelated with Age in the dataset, since turtles in your sample have done all the sneaking out they're going to. (Whoever heard of a sneaky mutated turtle not being a teenager?)
Nostril Size
Nostril Size has nothing to do with anything (. . . aside from providing a weak and redundant piece of evidence about clone turtles).
Turtle Weight
The weight of a regular turtle is given by the sum of their flesh weight, shell weight, and mutation weight. (A vampire turtle only has shell weight; a clone turtle is always exactly 20.4lb)
Flesh Weight
The unmutated flesh weight of a turtle is given by (20+[Age]+[Age]d6)/10 lb.
Shell Weight
The shell weight of a turtle is given by (5+2*[Shell Segments]+[Shell Segments]d4)/10 lb. (This means that shell weight is the only variable you should use when calculating the weight of a vampire turtle.)
Mutation Weight
A mutated turtle has 1d(20*[# of Abnormalities])/10 lb of extra weight. (This means each abnormality increases expected weight by about 1lb, and greatly increases expected variance).
Strategy
The optimal[1] predictions and decisions are as follows:
Turtle
Average Weight (lb)
Optimal Prediction (lb)
Abigail
20.1
22.5
Bertrand
17.3
18.9
Chartreuse
22.7
25.9
Dontanien
19.3
21.0
Espera
16.6
18.0
Flint
6.8
7.3
Gunther
25.7
30.6
Harold
20.4
20.4
Irene
21.5
23.9
Jacqueline
18.5
20.2
Leaderboard
Player
EV(gp)
Perfect Play (to within 0.1lb)
1723.17
gjm
1718.54
Malentropic Gizmo
1718.39
aphyer
1716.57
simon
1683.60
qwertyasdef
1674.54
Yonge[2]
1420.00
Just predicting 20lb for everything
809.65
Reflections
The intended theme of this game was modelling in the presence of as...
This is a followup to the D&D.Sci post I made ten days ago; if you haven't already read it, you should do so now before spoiling yourself.
Here is the web interactive I built to let you evaluate your solution; below is an explanation of the rules used to generate the dataset (my full generation code is available here, in case you're curious about details I omitted). You'll probably want to test your answer before reading any further.
Ruleset
Turtle Types
There are three types of turtle present in the swamp: normal turtles, clone turtles, and vampire turtles.
Clone turtles are magically-constructed beasts who are mostly identical. They always have six shell segments, bizarrely consistent physiology, and a weight of exactly 20.4lb. Harold is a clone turtle.
Vampire turtles can be identified by their gray skin and fangs. They're mostly like regular turtles, but their flesh no longer obeys gravity, which has some important implications for your modelling exercise. Flint is a vampire turtle.
Turtle characteristics
Age
Most of the other factors are based on the hidden variable Age. The Age distribution is based on turtles having an Age/200 chance of dying every year. Additionally, turtles under the age of 20 are prevented from leaving their homes until maturity, meaning they will be absent from both your records and the Tyrant's menagerie.
Wrinkles
Every non-clone turtle has an [Age]% chance of getting a new wrinkle each year.
Scars
Every non-clone turtle has a 10% chance of getting a new scar each year.
Shell Segments
A non-clone turtle is born with 7 shell segments; each year, they have a 1 in [current number of shell segments] chance of getting a new one.
Color
Turtles are born green; they turn grayish-green at some point between the ages of 23 and 34, then turn greenish-gray at some point between the ages of 35 and 46.
Miscellaneous Abnormalities
About half of turtles sneak into the high-magic parts of the swamp at least once during their adolescence. This mutates them, producing min(1d8, 1d10, 1d10, 1d12) Miscellanous Abnormalities.
This factor is uncorrelated with Age in the dataset, since turtles in your sample have done all the sneaking out they're going to. (Whoever heard of a sneaky mutated turtle not being a teenager?)
Nostril Size
Nostril Size has nothing to do with anything (. . . aside from providing a weak and redundant piece of evidence about clone turtles).
Turtle Weight
The weight of a regular turtle is given by the sum of their flesh weight, shell weight, and mutation weight. (A vampire turtle only has shell weight; a clone turtle is always exactly 20.4lb)
Flesh Weight
The unmutated flesh weight of a turtle is given by (20+[Age]+[Age]d6)/10 lb.
Shell Weight
The shell weight of a turtle is given by (5+2*[Shell Segments]+[Shell Segments]d4)/10 lb. (This means that shell weight is the only variable you should use when calculating the weight of a vampire turtle.)
Mutation Weight
A mutated turtle has 1d(20*[# of Abnormalities])/10 lb of extra weight. (This means each abnormality increases expected weight by about 1lb, and greatly increases expected variance).
Strategy
The optimal[1] predictions and decisions are as follows:
Turtle
Average Weight (lb)
Optimal Prediction (lb)
Abigail
20.1
22.5
Bertrand
17.3
18.9
Chartreuse
22.7
25.9
Dontanien
19.3
21.0
Espera
16.6
18.0
Flint
6.8
7.3
Gunther
25.7
30.6
Harold
20.4
20.4
Irene
21.5
23.9
Jacqueline
18.5
20.2
Leaderboard
Player
EV(gp)
Perfect Play (to within 0.1lb)
1723.17
gjm
1718.54
Malentropic Gizmo
1718.39
aphyer
1716.57
simon
1683.60
qwertyasdef
1674.54
Yonge[2]
1420.00
Just predicting 20lb for everything
809.65
Reflections
The intended theme of this game was modelling in the presence of as...