Question

Load the built-in "iris" dataset in RStudio and write code to perform the following:

(a) Obtain the summary statistics for the "Sepal.Length" variable (including mean, median, and standard deviation).
(b) Create a histogram of the "Sepal.Length" variable.
(c) Create a scatterplot of the "Sepal.Length" variable against the "Species" variable.
(d) Create a boxplot of the the "Sepal.Length" variable against the "Species" variable, setting x= Species, y= Sepal.Length, and group = Species. What do you observe about the different species of iris according to this plot? HINT: data(iris) will load the data when entered in your Console pane.

Answer 1

To analyze the "iris" dataset in RStudio, you can use R code to load the data, obtain summary statistics, and create various plots such as histograms and scatterplots. The resulting boxplot reveals differences among the species in terms of sepal length.

Step-by-step explanation:

To work with the built-in "iris" dataset in RStudio and perform the specified tasks, you can use the following R code:

1. Load the iris dataset:
   data(iris)
2. To obtain the summary statistics for the "Sepal.Length" variable (mean, median, and standard deviation):
   summary(iris$Sepal.Length)
   mean(iris$Sepal.Length)
   median(iris$Sepal.Length)
   sd(iris$Sepal.Length)
3. Create a histogram of the "Sepal.Length" variable:
   hist(iris$Sepal.Length)
4. Create a scatterplot of the "Sepal.Length" variable against the "Species" variable:
   plot(iris$Species, iris$Sepal.Length)
5. Create a boxplot of the "Sepal.Length" variable against the "Species" variable, with specific groupings:
   boxplot(Sepal.Length ~ Species, data = iris, main = "Sepal Length by Species", xlab = "Species", ylab = "Sepal Length")

From the resulting boxplot, we can observe that there are differences in the median sepal length across different species of iris. This visual representation allows us to easily compare the central tendency and dispersion of sepal length among the species.