auto = read.table("auto.data",header=T,na.strings="?")
auto$mpg01=rep(0,397)
auto$mpg01[auto$mpg>median(auto$mpg)]=1
library(ISLR)
library(MASS)
library(class)
train_bools <- (auto$year %% 2 == 0)
train_data = auto[train_bools,]
test_data = auto[!train_bools,]
help(knn)
help(knn)
     train <- rbind(iris3[1:25,,1], iris3[1:25,,2], iris3[1:25,,3])
     test <- rbind(iris3[26:50,,1], iris3[26:50,,2], iris3[26:50,,3])
train
test
?knn
     cl <- factor(c(rep("s",25), rep("c",25), rep("v",25)))
cl
length(cl)
length(train)
nrows(train)
nrow(train)
train.X
train.X = cbind(auto$horsepower,auto$displacement,auto$weight,auto$acceleration)[train_bools,]
train.X
test.X = cbind(auto$horsepower,auto$displacement,auto$weight,auto$acceleration)[!train_bools,]
test.X
train.X
train.mpg01 = auto$mpg01[train_bools]
train.mpg01
length(train.mpg01)
nrow(train.X)
knn(train.X,train.Y,train.mpg01,K=1)
knn(train.X,train.Y,train.mpg01,k=1)
knn(train.X,test.X,train.mpg01,k=1)
train.X
na.omit(train.X)
?na.omit
na.omit(train.X)
na.omit(train.X)
knn(na.omit(train.X),test.X,train.mpg01,k=1)
knn(na.omit(train.X),test.X,na.omit(train.mpg01),k=1)
knn(na.omit(train.X),na.omit(test.X),na.omit(train.mpg01),k=1)
train.mpg012 = na.omit(auto$mpg01)[train_bools]
train.mpg012
train.mpg01
nrow(train)
na.omit(auto)
auto
na.omit(auto)
summary(auto)
summary(na.omit(auto))
Auto = na.omit(auto)
auto = na.omit(auto)
ncol(auto)
nrow(auto)
auto <- na.omit(auto)
train_bools <- (auto$year %% 2 == 0)
train_data = auto[train_bools,]
test_data = auto[!train_bools,]
train.X = cbind(auto$horsepower,auto$displacement,auto$weight,auto$acceleration)[train_bools,]
test.X = cbind(auto$horsepower,auto$displacement,auto$weight,auto$acceleration)[!train_bools,]
train.mpg01 = auto$mpg01[train_bools]
knn.pred = knn(train.X,test.X,train.mpg01,k=1)
mean(knn.pred != auto$mpg01)
mean(knn.pred != test_data$mpg01)
knn.pred = knn(train.X,test.X,train.mpg01,k=2)
mean(knn.pred != test_data$mpg01)
knn.pred = knn(train.X,test.X,train.mpg01,k=3)
mean(knn.pred != test_data$mpg01)
knn.pred = knn(train.X,test.X,train.mpg01,k=4)
mean(knn.pred != test_data$mpg0)
knn.pred
length(knn.pred)
dim(knn.pred)
length(test_data)
ncol(test_data)
nrow(test_data)
q()