Final answer:
A scatterplot is used to graphically represent the strength and direction of a correlation between variables. Positive, negative, and zero correlations can be identified by the correlation coefficient (r), with the sign of r indicating the direction of the relationship.
Step-by-step explanation:
A scatterplot is a graphical view of the strength and direction of a correlation. When data is plotted on a scatterplot, the result can often be interpreted as a straight line if there is a direct relationship. This type of graph has two axes: a horizontal axis (x-axis) representing the independent variable, and a vertical axis (y-axis) representing the dependent variable.
There are three main types of correlations that can be identified in scatterplots:
- Positive correlation - indicated by a correlation coefficient (r) between 0 and 1, where the variables move in the same direction.
- Negative correlation - indicated by r between -1 and 0, where the variables move in opposite directions.
- Zero correlation - indicated by r equal to 0, where there is no apparent relationship between the variables.
The sign (positive or negative) of the correlation coefficient signifies the direction of the relationship, and the closer the value of r is to -1 or 1, the stronger the correlation.