March 26, 2017

The iris dataset

Fisher's iris data set gives the measurements in centimeters of the variables sepal length and width and petal length and width, respectively, for 50 flowers from each of 3 species of iris. The species are Iris setosa, versicolor, and virginica so a total of 150 measurements each with 5 observations.

The structure of the iris dataset is as follows:

## 'data.frame':    150 obs. of  5 variables:
##  $ Sepal.Length: num  5.1 4.9 4.7 4.6 5 5.4 4.6 5 4.4 4.9 ...
##  $ Sepal.Width : num  3.5 3 3.2 3.1 3.6 3.9 3.4 3.4 2.9 3.1 ...
##  $ Petal.Length: num  1.4 1.4 1.3 1.5 1.4 1.7 1.4 1.5 1.4 1.5 ...
##  $ Petal.Width : num  0.2 0.2 0.2 0.2 0.2 0.4 0.3 0.2 0.2 0.1 ...
##  $ Species     : Factor w/ 3 levels "setosa","versicolor",..: 1 1 1 1 1 1 1 1 1 1 ...

Irises…

Plot of comparison of petal length with petal width

Plot of comparison of sepal length with sepal width

Comments

  • The relationsip for petal length and and petal width seem to be tightly clustered with both lengths and widths for each species: virginica > versicolor > setosa.
  • Sepal length and width has considerable overlap for virginica and setosa, with virginica being larger in both dimensions.
  • For setosa, the sepal length is smaller but the sepal width tends to be larger than the other two species.

Thankyou.