source('../../Data/get_arsenic_data.R') DF = get_arsenic_data() m1 = lm(Arsenic_in_nail_ppm ~ Arsenic_in_water_ppm, data=DF) print(summary(m1)) plot(DF$Arsenic_in_water_ppm, DF$Arsenic_in_nail_ppm, type='p', pch=19, xlab='Arsenic in water (ppm)', ylab='Arsenic in toenail (ppm)') grid() abline(m1) m2 = lm(Arsenic_in_nail_ppm ~ 0 + Arsenic_in_water_ppm, data=DF) print(summary(m2)) plot(DF$Arsenic_in_water_ppm, DF$Arsenic_in_nail_ppm, type='p', pch=19, xlab='Arsenic in water (ppm)', ylab='Arsenic in toenail (ppm)') grid() abline(m2, col='green') abline(m1, col='red')