向 arulesViz 输入外部规则

Question

我有一个规则的 excel 文件：一列用于前因，另一列用于后果，其他用于支持等

我正在尝试创建一个“规则”对象以使用 arulesViz 绘制它们。

http://www.inside-r.org/packages/cran/arules/docs/rhs

new("rules", ...)

我正在尝试创建插槽

lhs:Object of class itemMatrix; the left-hand-sides of the rules (antecedents)
rhs:Object of class itemMatrix; the right-hand-sides of the rules (consequents)
quality:a data.frame

要创建 itemMatrix 我需要回到稀疏矩阵，但我认为这行不通，有没有办法将规则“导入”到 arulesViz？

Excel 文件：

Antec   Conseq      Supp      Conf
MMMMAAA MMAAAA  0.061945    0.5
MMM,MA  MMAAAA  0.071944    0.6
MMMMAAA MMAAA   0.053948    0.5
MMM,MA  MMAAA   0.054948    0.7
AAAAAA  AAAA    0.090909    0.5

Answer 1

一种方法是为规则创建一个 PMML 文件并使用read.PMML。从头开始创建规则对象有点棘手。这是一个例子：

library("arules")
l <- list(c("MMMMAAA"), c("MMM", "MA"), "MMMMAAA", c("MMM","MA"), "AAAAA")
r <- list("MMAAAA", "MMAAAA", "MMAAA", "MMAAA", "AAAA")
q <- data.frame(
     support = c(0.061945, 0.071944, 0.053948, 0.054948,0.090909), 
     confidence = c(.5, .6, .5, .7, .5),
     lift = c(1,1,1,1,1)
)
### Note that I also added lift since arulesViz uses 
### lift in some visualizations.


### find unique item labels
items <- unique(c(unlist(l), unlist(r)))

### encode data as a rules object
r <- new("rules", lhs = encode(l, items), 
   rhs = encode(r, items), quality = q)

inspect(r)

### use a visualization as a scatter plot.
library("arulesViz")
plot(r)

希望这会有所帮助！