Figure 4.

14 suggests that we can assign each feature vector \(\boldsymbol{x}\) in the iris data set to one of two clusters, based on the value of \(\boldsymbol{u}_{1}^{\top} \boldsymbol{x}\), where \(\boldsymbol{u}_{1}\) is the first principal component. Plot the sepal lengths against petal lengths and color the points for which \(\boldsymbol{u}_{1}^{\top} \boldsymbol{x}\) differently to points for which \(\boldsymbol{u}_{1}^{\top} \boldsymbol{x} \geqslant 1.

5\). To which species of iris do these clusters correspond?