Which of the following best describes the difference between $univariate$ data and $bivariate$ data?

• A. $Univariate$ data is used only for probability distributions, while $bivariate$ data is used only for hypothesis testing.
• B. $Univariate$ data consists of observations on a single variable, while $bivariate$ data consists of observations on two variables for each subject or case.
• C. $Univariate$ data always involves categorical variables, while $bivariate$ data always involves numerical variables.
• D. $Univariate$ data refers to data collected from two groups, while $bivariate$ data refers to data collected from one group.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the definition of univariate data. Univariate data consists of observations on a single variable. This means each data point represents one characteristic or measurement for each subject or case.
2. Step 2: Understand the definition of bivariate data. Bivariate data consists of observations on two variables for each subject or case. This means each data point includes two related measurements or characteristics.
3. Step 3: Compare the options given in the problem to these definitions. Identify which option correctly states that univariate data involves one variable and bivariate data involves two variables.
4. Step 4: Recognize that univariate data is not limited to probability distributions, nor is bivariate data limited to hypothesis testing. Also, univariate data can be numerical or categorical, and bivariate data can involve any types of variables.
5. Step 5: Conclude that the best description is the one stating that univariate data consists of observations on a single variable, while bivariate data consists of observations on two variables for each subject or case.