# 7.1߁@f[^̕
candy0 <- scale(candy, center=T, scale=F) # ϕ΍s
y <- candy0[,"sales"]    # ϐ̃xNg
X <- candy0[,2:3]        # ϐ̍spӂ
# ΉAW̐ 
b <-solve(t(X)%*%X)%*%t(X)%*%y
# Ot@Cɕۑ
attach(candy) #  f[^t[ candy ̕ϐg悤ɂ
yhat <- mean(sales)+X%*%b
error <- sales - yhat
candyresult <- data.frame(candy,yhat,error)
write.csv(candyresult, file = "output.csv" ,row.names = F)

# Rő֌W߂
r23 <- cor(temp,time)  # ϐԂ̑֌W
r <- cor(y,yhat)  # d֌W
determ <- r^2   # W coefficient of determination
