R语言LR逻辑回归实例

二分类实例去掉setosa类index <- which(iris$Species == 'setosa')iris <- iris[- index,]training <-iris  #抽样方法  ind<-sample(2,nrow(training),replace=TRUE,prob=c(0.7,0.3)) #对数据分成两部分，70%训练数据，30%检测数据nrow(training)行数  traindata<- training [ind==1,]  #训练集  testdata<- training [ind==2,]#二项分布族binomial--正态、指数、gamma、逆高斯、Poisson、二项fit <- glm(Species ~.,family=binomial(link='logit'),data=traindata)predict <- predict(fit,type='response',newdata=testdata)real <- testdata$Speciesres <- data.frame(real,predict =ifelse(predict>0.5,'virginca','versicorlor'))table(real,predict =ifelse(predict>0.5,'virginca','versicorlor'))