df <- read.delim('ais.txt')
sapply(df,class)
summary(df)
cor(df[-c(1,2)])
plot(df[-c(1,2)], col = df$Sex)
x_v = df$Wt
y_v = df$Ht
B1 = sum((y_v-mean(y_v))*(x_v-mean(x_v)))/sum((x_v-mean(x_v))^2)
B0 = mean(y_v)-B1*mean(x_v)
plot(df$Wt, df$Ht)
abline(B0,B1)

y_pred <- B0 + B1x
points(x_v, y_pred, col = "red")