Density Plot

It's like a Histogram, but smoothed out

With Histogram

hist(pData$AGEP, breaks=12, col="red", prob=T)
dens = density(pData$AGEP, adjust=2) 
lines(dens, col="blue", lwd=2)

Without Histogram

dens = density(pData$AGEP)
plot(dens, lwd=3, col="blue")
  • density-plots.png

Bivariate Analysis

  • this plot can also be used with two variables
  • density-2vars.png
  • it is more convenient than Histograms for doing that
  • since it uses plot, not bars
densM = density(pData$AGEP[which(pData$SEX==1)])
densF = density(pData$AGEP[which(pData$SEX==2)])
plot(densM, lwd=3, col="blue")
lines(densF, lwd=3, col="orange")