Bivariate data consist of paired observations (x_i,y_i), for i=1,2,,n, recorded on two numerical variables for the same individuals or items. **Role** | **Meaning** Explanatory variable | The variable used to explain or predict variation in the other variable. Response variable | The variable whose value is modelled or predicted. Independent/dependent variables | Use these causal terms only when the design or context justifies a controlled input and resulting output. A scatter diagram plots each ordered pair on axes whose ranges and quantity labels cover the observed data. A visible pattern indicates association, not necessarily causation. An outlier is an observation unusually far from the overall pattern. It may be genuine, or it may result from measurement, recording or data-entry error; investigate before excluding it.

Bivariate data consist of paired observations \((x_i,y_i)\), for \(i=1,2,\ldots,n\), recorded on two numerical variables for the same individuals or items.

A scatter diagram plots each ordered pair on axes whose ranges and quantity labels cover the observed data. A visible pattern indicates association, not necessarily causation.

An outlier is an observation unusually far from the overall pattern. It may be genuine, or it may result from measurement, recording or data-entry error; investigate before excluding it.

Bivariate Data, Variables and Scatter Diagrams

Bivariate Data, Variables and Scatter Diagrams

Role	Meaning
Explanatory variable	The variable used to explain or predict variation in the other variable.
Response variable	The variable whose value is modelled or predicted.
Independent/dependent variables	Use these causal terms only when the design or context justifies a controlled input and resulting output.