Question

我正在使用协同过滤构建产品推荐引擎（在R中）。为了使更多有利可图的项目位于建议的顶部，我们开发了一个灵活业务规则，如图1所示。业务规则应用于对推荐器输出进行排序。

+---------------+----------+-----------------+
| Sort Priority | Level 1  | Level 2         |
+---------------+----------+-----------------+
| 1             | Brand    | Versatile Foods |
+---------------+----------+-----------------+
|               |          | Agro            |
+---------------+----------+-----------------+
|               |          | Specialty Foods |
+---------------+----------+-----------------+
|               |          |                 |
+---------------+----------+-----------------+
| 2             | Category | Dairy           |
+---------------+----------+-----------------+
|               |          | Produce         |
+---------------+----------+-----------------+
|               |          | Seafood         |
+---------------+----------+-----------------+
|               |          |                 |
+---------------+----------+-----------------+
| 3             | Seasonal | Y               |
+---------------+----------+-----------------+
|               |          | N               |
+---------------+----------+-----------------+
            figure 1

业务规则： 对表格进行排序时，“品牌”列应优先于   应优先于季节性的类别。这由列排序优先级的值决定。

在品牌专栏中进行分类时，Versatile Foods优先于Agro和Agro   特色食品。   如果未显示品牌列中的值   在规则中，值必须按字母顺序排序。

  相同的排序逻辑应该应用于规则定义中的每个条目。

随着推荐算法的发展。可以更改/编辑业务规则以使其具有更少或更多级别。对于例如未来可能会添加一个额外的level1条目，比如Type（Kosher，Vegan，Halal）等。规则将如下所示：

+---------------+----------+-----------------+
| Sort Priority | Level 1  | Level 2         |
+---------------+----------+-----------------+
| 1             | Brand    | Versatile Foods |
+---------------+----------+-----------------+
|               |          | Agro            |
+---------------+----------+-----------------+
|               |          | Specialty Foods |
+---------------+----------+-----------------+
|               |          |                 |
+---------------+----------+-----------------+
| 2             | Category | Dairy           |
+---------------+----------+-----------------+
|               |          | Produce         |
+---------------+----------+-----------------+
|               |          | Seafood         |
+---------------+----------+-----------------+
|               |          |                 |
+---------------+----------+-----------------+
| 3             | Type     | Kosher          |
+---------------+----------+-----------------+
|               |          | Halal           |
+---------------+----------+-----------------+
|               |          | Vegan           |
+---------------+----------+-----------------+
|               |          |                 |
+---------------+----------+-----------------+
| 4             | Seasonal | Y               |
+---------------+----------+-----------------+
|               |          | N               |
+---------------+----------+-----------------+
            figure 2

我需要帮助在R中构建一个脚本，它将按上述业务规则对上表（加载到数据帧）进行排序。我想要解决的真正问题是，每次向规则添加新条目时，我都不想更改代码。

输入数据（由推荐引擎输出）将是这种类型（图3）。

+-----+-----------------+----------+----------+
| SKU | Brand           | Category | Seasonal |
+-----+-----------------+----------+----------+
| 1   | Versatile Foods | Dairy    | Y        |
+-----+-----------------+----------+----------+
| 2   | Agro            | Produce  | Y        |
+-----+-----------------+----------+----------+
| 3   | Specialty Foods | Seafood  | N        |
+-----+-----------------+----------+----------+
| 4   | Agro            | Produce  | N        |
+-----+-----------------+----------+----------+
| 5   | Specialty Foods | Organic  | Y        |
+-----+-----------------+----------+----------+
| 6   | Agro            | Meat     | N        |
+-----+-----------------+----------+----------+
| 7   | Versatile Foods | Seafood  | N        |
+-----+-----------------+----------+----------+
| 8   | USA Bread       | Bakery   | Y        |
+-----+-----------------+----------+----------+
| 9   | Specialty Foods | Seafood  | N        |
+-----+-----------------+----------+----------+
| 10  | Versatile Foods | Seafood  | N        |
+-----+-----------------+----------+----------+
                  figure 3

使用如图1中的规则定义，脚本的输出应该如下表所示。
请注意Brand = USA业务规则中没有出现的面包如何放在排序列表的底部。
另外，对于第4项和第6项，记录类别=＆＃39;生产＆＃39;被列在记录的上方，类别=＆＃39;肉类＆＃39;作为条目＆＃39;肉类＆＃39;没有在商业规则中找到但是“生产”＃39;是。

+-----+-----------------+----------+----------+
| SKU | Brand           | Category | Seasonal |
+-----+-----------------+----------+----------+
| 1   | Versatile Foods | Dairy    | Y        |
+-----+-----------------+----------+----------+
| 7   | Versatile Foods | Seafood  | N        |
+-----+-----------------+----------+----------+
| 10  | Versatile Foods | Seafood  | N        |
+-----+-----------------+----------+----------+
| 2   | Agro            | Produce  | Y        |
+-----+-----------------+----------+----------+
| 4   | Agro            | Produce  | N        |
+-----+-----------------+----------+----------+
| 6   | Agro            | Meat     | N        |
+-----+-----------------+----------+----------+
| 3   | Specialty Foods | Seafood  | N        |
+-----+-----------------+----------+----------+
| 9   | Specialty Foods | Seafood  | N        |
+-----+-----------------+----------+----------+
| 5   | Specialty Foods | Organic  | Y        |
+-----+-----------------+----------+----------+
| 8   | USA bread       | Bakery   | Y        |
+-----+-----------------+----------+----------+
                 figure 4

Answer 1

您可以使用因子编码来订购您想要的东西。例如：

> lvl <- c('Versatile Foods', 'Agro', 'Specialty Foods')
> lvl <- append(lvl, sort(setdiff(unique(df$Brand), lvl)))
> 
> df$Brand <- factor(df$Brand, levels=lvl)
> 
> lvl <- c("Dairy", "Produce", "Seafood")
> lvl <- append(lvl, sort(setdiff(unique(df$Category), lvl)))
> 
> df$Category <- factor(df$Category, levels=lvl)
> 
> df$Seasonal <- factor(df$Seasonal, levels=c('Y', 'N'))
> 
> 
> df[order(df$Brand, df$Category, df$Seasonal), ]
   SKU           Brand Category Seasonal
1    1 Versatile Foods    Dairy        Y
7    7 Versatile Foods  Seafood        N
10  10 Versatile Foods  Seafood        N
2    2            Agro  Produce        Y
4    4            Agro  Produce        N
6    6            Agro  Produce        N
3    3 Specialty Foods  Seafood        N
9    9 Specialty Foods  Seafood        N
5    5 Specialty Foods  Organic        Y
8    8       USA Bread   Bakery        Y

Answer 2

此方法涉及定义排序排名表，然后在与主表合并后使用新列执行排序。

library(dplyr)
rank <- data_frame(Brand = c('Versatile Foods','Agro','Specialty Foods'),
                   Brand_rank = c(1,2,3))
df <- left_join(df, rank, on="Brand") %>%
    arrange(Brand_rank, Brand, Category, Seasonal) %>%
    select(-Brand_rank)
df
# A tibble: 10 × 4
#    SKU           Brand Category Seasonal
#    <dbl>           <chr>    <chr>    <chr>
#1      1 Versatile Foods    Dairy        Y
#2      7 Versatile Foods  Seafood        N
#3     10 Versatile Foods  Seafood        N
#4      4            Agro  Produce        N
#5      6            Agro  Produce        N
#6      2            Agro  Produce        Y
#7      5 Specialty Foods  Organic        Y
#8      3 Specialty Foods  Seafood        N
#9      9 Specialty Foods  Seafood        N
#10     8       USA Bread   Bakery        Y

按灵活标准排序

2 个答案: