1.7 Fisher's irises: Sir Ronald Aylmer Fisher was an English statistician, evolutionary biologist, and geneticist who worked on a data set that contained sepal length and width, and petal length and width from three species of iris flowers (setosa, versicolor and virginica). There were 58 flowers from each species in the data set. a) How many cases were included in the data? b) How many numerical variables are included in the data? Indicate what they are, and if they are continuous or discrete. Four continuous variables: sepal length, sepal width, petal length, and petal width Two discrete variables: sepal and petal Two continuous variables: length and width Four discrete variables: sepal length, sepal width, petal length, and petal width c) How many categorical variables are included in the data, and what are they? List the corresponding levels (categories). Three categorical variables: setosa, versicolor, and virginica Two categorical variables: species (levels: setosa, versicolor, and virginica) and flower part (levels: sepal and petal) One categorical variable: species (levels: setosa, versicolor, and virginica)
1.7 Fisher's irises: Sir Ronald Aylmer Fisher was an English statistician, evolutionary biologist, and geneticist who worked on a data set that contained sepal length and width, and petal length and width from three species of iris flowers (setosa, versicolor and virginica). There were 58 flowers from each species in the data set.
a) How many cases were included in the data?
b) How many numerical variables are included in the data? Indicate what they are, and if they are continuous or discrete.
- Four continuous variables: sepal length, sepal width, petal length, and petal width
- Two discrete variables: sepal and petal
- Two continuous variables: length and width
- Four discrete variables: sepal length, sepal width, petal length, and petal width
c) How many categorical variables are included in the data, and what are they? List the corresponding levels (categories).
- Three categorical variables: setosa, versicolor, and virginica
- Two categorical variables: species (levels: setosa, versicolor, and virginica) and flower part (levels: sepal and petal)
- One categorical variable: species (levels: setosa, versicolor, and virginica)
The data set contained sepal length and width, and petal length and width from three species of iris flowers.
There are 58 flowers from each species.
There are types of variables.
- Numerical variable
The variable which takes the numerical value is called the numerical variable.
The numerical variable is classified into two types.
- Discrete variable
The variable can take only a finite number of values. like 12,15,48,etc. An example of a discrete variable is the number of cars on the road
- Continuous variable
The variable can take an infinite set of values. like 0.01,0.025,2.5,etc. An example of a continuous variable is the length of a square.
- Categorical variable
The categorical variable is the qualitative variable or the variable based on characteristics that can be divided into groups.
The categorical variable is classified into two types.
- A nominal variable
The categorical variable where the order is not indicated is called the nominal variable
- Ordinal variable
The categorical variable where the order is indicated is called the ordinal variable
Trending now
This is a popular solution!
Step by step
Solved in 4 steps
