> Question 2a)
> I am also working with arules package and I have the following problem
> let suppose the matrix b like:
> b<-matrix(c(1,1,1,1,1,1,0,0,1,1,1,1,0,0,1,1,0,1,1,1,1,1,1,1),nrow=6)
> rownames(b)=c("T1", "T2", "T3",
"T4", "T5", "T6")
> colnames(b)=c("It1", "It2", "It3",
"It4")
> bt<-as(b, "transactions")
> rules<-apriori(bt, parameter = list(maxlen=2))
> k<-inspect(rules)
> k
> ##we obtain
> lhs rhs support confidence lift
> 1 {} => {It4} 1.0000000 1 1.0
> 2 {} => {It1} 1.0000000 1 1.0
> 3 {It3} => {It2} 0.5000000 1 1.5
> 4 {It3} => {It4} 0.5000000 1 1.0
> 5 {It3} => {It1} 0.5000000 1 1.0
> 6 {It2} => {It4} 0.6666667 1 1.0
> 7 {It2} => {It1} 0.6666667 1 1.0
> 8 {It4} => {It1} 1.0000000 1 1.0
> 9 {It1} => {It4} 1.0000000 1 1.0
>
> WRITE(rules)
> ##we obtain
> "rules" "support" "confidence"
"lift"
> "1" "{} => {It4}" 1 1 1
> "2" "{} => {It1}" 1 1 1
> "3" "{It3} => {It2}" 0.5 1 1.5
> "4" "{It3} => {It4}" 0.5 1 1
> "5" "{It3} => {It1}" 0.5 1 1
> "6" "{It2} => {It4}" 0.666666666666667 1 1
> "7" "{It2} => {It1}" 0.666666666666667 1 1
> "8" "{It4} => {It1}" 1 1 1
> "9" "{It1} => {It4}" 1 1 1
> I want to convert this in a matrix or data frame and the result should be
> something like this
> ##we obtain
> rules support confidence lift
> 1 {}=>{It4} 1.0000000 1 1.0
> 2 {}=>{It1} 1.0000000 1 1.0
> 3 {It3}=>{It2} 0.5000000 1 1.5
> 4 {It3}=>{It4} 0.5000000 1 1.0
> 5 {It3}=>{It1} 0.5000000 1 1.0
> 6 {It2}=>{It4} 0.6666667 1 1.0
> 7 {It2}=>{It1} 0.6666667 1 1.0
> 8 {It4}=>{It1} 1.0000000 1 1.0
> 9 {It1}=>{It4} 1.0000000 1 1.0
R> data.frame(rules = labels(rules), quality(rules))
rules support confidence lift
1 {} => {It4} 1.0000000 1 1.0
2 {} => {It1} 1.0000000 1 1.0
3 {It3} => {It2} 0.5000000 1 1.5
4 {It3} => {It4} 0.5000000 1 1.0
5 {It3} => {It1} 0.5000000 1 1.0
6 {It2} => {It4} 0.6666667 1 1.0
7 {It2} => {It1} 0.6666667 1 1.0
8 {It4} => {It1} 1.0000000 1 1.0
9 {It1} => {It4} 1.0000000 1 1.0
> In another hand is it possible to obtain all the rules where
lHS<=>rhs?. In
> our last example that means to obtain
> lhs rhs support confidence lift
> 8 {It4} => {It1} 1.0000000 1 1.0
> 9 {It1} => {It4} 1.0000000 1 1.0
This is a little more tricky.
We can create a new set of rules with rhs and lhs reversed and then see
if these reversed rules match some of the original rules.
> rulesRev <- new("rules", rhs=lhs(rules), lhs=rhs(rules))
> m <- match(rules, rulesRev, nomatch=0)
> inspect(rules[m,])
lhs rhs support confidence lift
1 {It1} => {It4} 1 1 1
2 {It4} => {It1} 1 1 1
Maybe there is an easier way. I have to think about it.
-Michael
> Thanks again Alberto
>
--
Michael Hahsler
email: michael at hahsler.net
web: http://michael.hahsler.net