Repeating random choice












0












$begingroup$


Let's say I have 10 shirts (A to J) and I'd like to randomly wear a different one each day.



So, the one I wore yesterday (let's say shirt J) has 0% chance of being chosen today; The one I wore the day before (shirt I) has a little chance of being chosen today; ... the one I wore the farthest away in time has the greatest chance of being chosen today.



Also let's say that for the last 10 days I used all 10 different shirts in alphabetical order, so my choices, ordered from most desired to least desired are "A-B-C-D-E-F-G-H-I-J".



So, what is the best distribution of probabilities for each shirt?



Using an idea I had with the golden ratio (fibonacci numbers), I came up with this (that hopefully scales well for larger number of items)




id f s/f
A 34 39% (34/88)
B 21 24% (24/88)
C 13 15%
D 8 9%
E 5 6%
F 3 3%
G 2 2%
H 1 1%
I 1 1% ( 1/88)
J 0 0%
-----------
sum 88 100%


Assuming I selected shirt B today, tomorrow's order would be "A-C-D-E-F-G-H-I-J-B"





My crazy old method involved repeated interval shuffles from least desired to most desired group:




  1. Shuffle last 4: ABCDEF(ghij) let's say shuffling didn't reorder

  2. Shuffle next 4: ABCDE(fghi)J

  3. Shuffle next 4: ABCD(efgh)IJ

  4. Shuffle next 4: ABC(defg)HIJ

  5. Shuffle next 4: AB(cdef)GHIJ

  6. Shuffle next 4: A(bcde)FGHIJ

  7. Shuffle next 4: (abcd)EFGHIJ


The next day, make the shirt I used today the last one.



but I feel it's not adequate enough.










share|cite|improve this question











$endgroup$












  • $begingroup$
    For $k=1,ldots, N$, pick the shirt of "age" $k$ with porbability $k/H_N$, where $H_N=sum_{k=1}^Nfrac 1k$ is the $N$the harmonic number. Note that this (i.e., the demand for the probability being inversely proportional to the age) makes it more likely to repeat yesterday's shirt
    $endgroup$
    – Hagen von Eitzen
    Dec 5 '18 at 20:52
















0












$begingroup$


Let's say I have 10 shirts (A to J) and I'd like to randomly wear a different one each day.



So, the one I wore yesterday (let's say shirt J) has 0% chance of being chosen today; The one I wore the day before (shirt I) has a little chance of being chosen today; ... the one I wore the farthest away in time has the greatest chance of being chosen today.



Also let's say that for the last 10 days I used all 10 different shirts in alphabetical order, so my choices, ordered from most desired to least desired are "A-B-C-D-E-F-G-H-I-J".



So, what is the best distribution of probabilities for each shirt?



Using an idea I had with the golden ratio (fibonacci numbers), I came up with this (that hopefully scales well for larger number of items)




id f s/f
A 34 39% (34/88)
B 21 24% (24/88)
C 13 15%
D 8 9%
E 5 6%
F 3 3%
G 2 2%
H 1 1%
I 1 1% ( 1/88)
J 0 0%
-----------
sum 88 100%


Assuming I selected shirt B today, tomorrow's order would be "A-C-D-E-F-G-H-I-J-B"





My crazy old method involved repeated interval shuffles from least desired to most desired group:




  1. Shuffle last 4: ABCDEF(ghij) let's say shuffling didn't reorder

  2. Shuffle next 4: ABCDE(fghi)J

  3. Shuffle next 4: ABCD(efgh)IJ

  4. Shuffle next 4: ABC(defg)HIJ

  5. Shuffle next 4: AB(cdef)GHIJ

  6. Shuffle next 4: A(bcde)FGHIJ

  7. Shuffle next 4: (abcd)EFGHIJ


The next day, make the shirt I used today the last one.



but I feel it's not adequate enough.










share|cite|improve this question











$endgroup$












  • $begingroup$
    For $k=1,ldots, N$, pick the shirt of "age" $k$ with porbability $k/H_N$, where $H_N=sum_{k=1}^Nfrac 1k$ is the $N$the harmonic number. Note that this (i.e., the demand for the probability being inversely proportional to the age) makes it more likely to repeat yesterday's shirt
    $endgroup$
    – Hagen von Eitzen
    Dec 5 '18 at 20:52














0












0








0





$begingroup$


Let's say I have 10 shirts (A to J) and I'd like to randomly wear a different one each day.



So, the one I wore yesterday (let's say shirt J) has 0% chance of being chosen today; The one I wore the day before (shirt I) has a little chance of being chosen today; ... the one I wore the farthest away in time has the greatest chance of being chosen today.



Also let's say that for the last 10 days I used all 10 different shirts in alphabetical order, so my choices, ordered from most desired to least desired are "A-B-C-D-E-F-G-H-I-J".



So, what is the best distribution of probabilities for each shirt?



Using an idea I had with the golden ratio (fibonacci numbers), I came up with this (that hopefully scales well for larger number of items)




id f s/f
A 34 39% (34/88)
B 21 24% (24/88)
C 13 15%
D 8 9%
E 5 6%
F 3 3%
G 2 2%
H 1 1%
I 1 1% ( 1/88)
J 0 0%
-----------
sum 88 100%


Assuming I selected shirt B today, tomorrow's order would be "A-C-D-E-F-G-H-I-J-B"





My crazy old method involved repeated interval shuffles from least desired to most desired group:




  1. Shuffle last 4: ABCDEF(ghij) let's say shuffling didn't reorder

  2. Shuffle next 4: ABCDE(fghi)J

  3. Shuffle next 4: ABCD(efgh)IJ

  4. Shuffle next 4: ABC(defg)HIJ

  5. Shuffle next 4: AB(cdef)GHIJ

  6. Shuffle next 4: A(bcde)FGHIJ

  7. Shuffle next 4: (abcd)EFGHIJ


The next day, make the shirt I used today the last one.



but I feel it's not adequate enough.










share|cite|improve this question











$endgroup$




Let's say I have 10 shirts (A to J) and I'd like to randomly wear a different one each day.



So, the one I wore yesterday (let's say shirt J) has 0% chance of being chosen today; The one I wore the day before (shirt I) has a little chance of being chosen today; ... the one I wore the farthest away in time has the greatest chance of being chosen today.



Also let's say that for the last 10 days I used all 10 different shirts in alphabetical order, so my choices, ordered from most desired to least desired are "A-B-C-D-E-F-G-H-I-J".



So, what is the best distribution of probabilities for each shirt?



Using an idea I had with the golden ratio (fibonacci numbers), I came up with this (that hopefully scales well for larger number of items)




id f s/f
A 34 39% (34/88)
B 21 24% (24/88)
C 13 15%
D 8 9%
E 5 6%
F 3 3%
G 2 2%
H 1 1%
I 1 1% ( 1/88)
J 0 0%
-----------
sum 88 100%


Assuming I selected shirt B today, tomorrow's order would be "A-C-D-E-F-G-H-I-J-B"





My crazy old method involved repeated interval shuffles from least desired to most desired group:




  1. Shuffle last 4: ABCDEF(ghij) let's say shuffling didn't reorder

  2. Shuffle next 4: ABCDE(fghi)J

  3. Shuffle next 4: ABCD(efgh)IJ

  4. Shuffle next 4: ABC(defg)HIJ

  5. Shuffle next 4: AB(cdef)GHIJ

  6. Shuffle next 4: A(bcde)FGHIJ

  7. Shuffle next 4: (abcd)EFGHIJ


The next day, make the shirt I used today the last one.



but I feel it's not adequate enough.







probability algorithms random






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Dec 6 '18 at 10:51







pmg

















asked Dec 5 '18 at 20:23









pmgpmg

1235




1235












  • $begingroup$
    For $k=1,ldots, N$, pick the shirt of "age" $k$ with porbability $k/H_N$, where $H_N=sum_{k=1}^Nfrac 1k$ is the $N$the harmonic number. Note that this (i.e., the demand for the probability being inversely proportional to the age) makes it more likely to repeat yesterday's shirt
    $endgroup$
    – Hagen von Eitzen
    Dec 5 '18 at 20:52


















  • $begingroup$
    For $k=1,ldots, N$, pick the shirt of "age" $k$ with porbability $k/H_N$, where $H_N=sum_{k=1}^Nfrac 1k$ is the $N$the harmonic number. Note that this (i.e., the demand for the probability being inversely proportional to the age) makes it more likely to repeat yesterday's shirt
    $endgroup$
    – Hagen von Eitzen
    Dec 5 '18 at 20:52
















$begingroup$
For $k=1,ldots, N$, pick the shirt of "age" $k$ with porbability $k/H_N$, where $H_N=sum_{k=1}^Nfrac 1k$ is the $N$the harmonic number. Note that this (i.e., the demand for the probability being inversely proportional to the age) makes it more likely to repeat yesterday's shirt
$endgroup$
– Hagen von Eitzen
Dec 5 '18 at 20:52




$begingroup$
For $k=1,ldots, N$, pick the shirt of "age" $k$ with porbability $k/H_N$, where $H_N=sum_{k=1}^Nfrac 1k$ is the $N$the harmonic number. Note that this (i.e., the demand for the probability being inversely proportional to the age) makes it more likely to repeat yesterday's shirt
$endgroup$
– Hagen von Eitzen
Dec 5 '18 at 20:52










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