使用 R 中的人口比率和 min/max 标准将价值分配给区域

Distribute value to zones using population ratio and min/max criteria in R

我有以下数据:

require("data.table")
dt1 <- data.table(ZONE = c("A34","G345","H62","D563","T63","P983","S24","J54","W953","L97","V56","R99"), POPULATION = c(40,110,80,70,90,90,130,140,80,30,80,50), MIN = c(1,0,0,1,0,1,0,1,1,0,1,1), MAX = c(10,9,2,11,12,8,5,3,2,0,8,8))

我想向这些按人口加​​权的区域分发 50 顶帽子。但是,其中一些区域至少需要 1 顶帽子,而其他区域只能收到很少的帽子或根本不需要帽子。

有没有一种方法可以根据人口分配 50 顶帽子(尽可能按比例分配),但要考虑最小和最大标准,并在一个区域无法分配时将帽子分配重新分配给其他区域'没有收到 any/anymore?例如如果根据精确的比例分配,一个区域应分配 20 顶帽子但只能接受 10 顶,则应将其他 10 顶分配给按其人口加权的其他区域。

此函数执行您描述的算法。

它首先检查您是否有足够的帽子来满足最低要求。如果不是,它会抛出一个错误。

然后它会查看是否有足够多的帽子进行循环,在这种情况下它会给出最多的帽子。

否则,它分配最小数量的帽子,并从剩余的帽子中减去这个总和。然后它会循环,给剩余行一顶帽子,当前帽子和最大帽子之间的最大差距乘以人口规模,直到没有帽子可以分配。

distribute_hats <- function(df, hats)
{
  if (hats <  sum(df$MIN)) stop("Not enough hats to go round!")
  if (hats >= sum(df$MAX)) {df$HATS <- df$MAX; return(df)}
  df$HATS  <- df$MIN
  hats     <- hats - sum(df$MIN)
  while(hats)
  {
    weights  <- df$HATS/df$POPULATION
    allowed  <- which(df$HATS < df$MAX)
    smallest <- which.min(weights[allowed])[1]
    df$HATS[allowed][smallest] <- df$HATS[allowed][smallest] + 1
    hats <- hats - 1
  }

  return(df)
}

现在我们用合理的数字试试:

dt1 %>% distribute_hats(50)
#>     ZONE POPULATION MIN MAX HATS
#>  1:  A34         40   1  10    3
#>  2: G345        110   0   9    8
#>  3:  H62         80   0   2    2
#>  4: D563         70   1  11    5
#>  5:  T63         90   0  12    6
#>  6: P983         90   1   8    6
#>  7:  S24        130   0   5    5
#>  8:  J54        140   1   3    3
#>  9: W953         80   1   2    2
#> 10:  L97         30   0   0    0
#> 11:  V56         80   1   8    6
#> 12:  R99         50   1   8    4

dt1 %>% distribute_hats(10)
#>     ZONE POPULATION MIN MAX HATS
#>  1:  A34         40   1  10    1
#>  2: G345        110   0   9    1
#>  3:  H62         80   0   2    1
#>  4: D563         70   1  11    1
#>  5:  T63         90   0  12    1
#>  6: P983         90   1   8    1
#>  7:  S24        130   0   5    0
#>  8:  J54        140   1   3    1
#>  9: W953         80   1   2    1
#> 10:  L97         30   0   0    0
#> 11:  V56         80   1   8    1
#> 12:  R99         50   1   8    1

和边缘情况:

dt1 %>% distribute_hats(1000)
#>     ZONE POPULATION MIN MAX HATS
#>  1:  A34         40   1  10   10
#>  2: G345        110   0   9    9
#>  3:  H62         80   0   2    2
#>  4: D563         70   1  11   11
#>  5:  T63         90   0  12   12
#>  6: P983         90   1   8    8
#>  7:  S24        130   0   5    5
#>  8:  J54        140   1   3    3
#>  9: W953         80   1   2    2
#> 10:  L97         30   0   0    0
#> 11:  V56         80   1   8    8
#> 12:  R99         50   1   8    8

reprex package (v0.3.0)

于 2020-05-09 创建

我不确定。听起来像是优化或线性规划任务

函数如下:

allocate <- function(dt, N){
  if(N>dt[,sum(MAX)])
    stop("Too many hats to go around")

  if(N<dt[,sum(MIN)])
    stop("Not enough hats to go around")

# Allocate hats initially based on proportion but use clamping
  dt[, HATS := pmax(MIN, pmin(MAX, round(N * +(MAX>0) * POPULATION / sum(POPULATION[MAX>0]))))]

  n <- N - dt[,sum(HATS)]      
  if(n==0)  # All hats accouted for
    return(dt)

  if(n>0){  # Allocate the extra hats, again proportional to pop with clamping
    dt[HATS<MAX, HATS := HATS + pmax(MIN, pmin(MAX, 
              round(n * +(MAX>0) * POPULATION / sum(POPULATION[MAX>0]))))]
  } else {  # Or subtract the superfluous hats, according to pop
    dt[HATS>MIN, HATS := HATS - pmax(MIN, pmin(MAX, 
              round(abs(n) * +(MAX>0) * POPULATION / sum(POPULATION[MAX>0]))))]
  }

  n <- N - dt[,sum(HATS)]  # Check again
  if(n==0)  # All hats accouted for
    return(dt)

  if(n>0){  # This time, just add 1 hat to those that require them
    dt[HATS<MAX, i:=.I][i<=n, HATS := HATS + 1]
  } else {  # Or reduce the number of hats by one
    dt[HATS>MIN, i:=.I][i<=abs(n), HATS := HATS - 1]
  }

  dt[, i:=NULL]  # Remove this guy
  return(dt)
}

测试 50:

dt2 <- allocate(dt1, 50)
dt2
    ZONE POPULATION MIN MAX HATS
 1:  A34         40   1  10    2
 2: G345        110   0   9    8
 3:  H62         80   0   2    2
 4: D563         70   1  11    5
 5:  T63         90   0  12    7
 6: P983         90   1   8    7
 7:  S24        130   0   5    5
 8:  J54        140   1   3    3
 9: W953         80   1   2    2
10:  L97         30   0   0    0
11:  V56         80   1   8    5
12:  R99         50   1   8    4

分配了 50 顶帽子。

它可能不优雅或数学上不合理,但 that 是我对 what 的尝试,它是值得的。希望能有点用。

将此公式化为整数规划,其中 objective 函数根据最小和最大分配约束最小化分配和目标分配之间的平方和:

dt1[, TARGET := POPULATION / sum(POPULATION) * TOTAL]

system.time({
    library(CVXR)
    x <- Variable(nrow(dt1), integer=TRUE)
    mini <- dt1$MIN
    maxi <- dt1$MAX
    target <- dt1$TARGET
    obj <- Minimize(sum_squares(x - target))
    constr <- list(mini <= x, x <= maxi, sum(x) == TOTAL)
    prob <- Problem(obj, constr)
    result <- solve(prob)
})
#   user  system elapsed 
#   1.60    0.17    1.76 


dt1[, ALLOCATION := as.integer(round(result$getValue(x)))]

输出:

    ZONE POPULATION MIN MAX   TARGET ALLOCATION
 1:  A34         40   1  10 2.020202          4
 2: G345        110   0   9 5.555556          7
 3:  H62         80   0   2 4.040404          2
 4: D563         70   1  11 3.535354          5
 5:  T63         90   0  12 4.545455          6
 6: P983         90   1   8 4.545455          6
 7:  S24        130   0   5 6.565657          5
 8:  J54        140   1   3 7.070707          3
 9: W953         80   1   2 4.040404          2
10:  L97         30   0   0 1.515152          0
11:  V56         80   1   8 4.040404          6
12:  R99         50   1   8 2.525253          4

数据:

library(data.table)
dt1 <- data.table(ZONE = c("A34","G345","H62","D563","T63","P983","S24","J54","W953","L97","V56","R99"), 
  POPULATION = c(40,110,80,70,90,90,130,140,80,30,80,50), 
  MIN = c(1,0,0,1,0,1,0,1,1,0,1,1), 
  MAX = c(10,9,2,11,12,8,5,3,2,0,8,8))
TOTAL <- 50L