A scatter diagram shows the relationship between two variables and is an excellent data visualization tool. Keep reading to learn about scatter diagrams, what they are, how they work, and how to make one of your own.
What is a scatter diagram?
Scatter diagrams or scatter plots are graphing tools that allow you to visualize the relationship between two variables. The data is displayed as points on a graph, with the x-axis representing one variable and the y-axis representing the other.
How do you create a scatter diagram?
To create a scatter diagram, you first need to gather data for both variables. Then, in Excel or another graphing software, create a new chart and select “Scatter” as the type. Next, input your data into the appropriate places on the graph. Below, we’ll describe the process in more detail.
Select the data to be plotted.
When selecting the data to be plotted on a scatter diagram, it is important to keep in mind that the axes on the graph will reflect the scale of the data. For example, if you are plotting the average yearly income for a group of people against their age, you would want to use an axis that reflects income (such as $0-$100,000) and another axis that reflects age (such as 0-20, 21-40, etc). It is also important to make sure that there is a linear relationship between the two variables being plotted; otherwise, your graph will be meaningless.
Plot the points representing the data.
To make a scatter diagram, you will need to plot the points representing the data. The x-axis should represent the independent variable (the one you are changing) and the y-axis should represent the dependent variable (the one you are measuring). You can use a ruler or a calculator to help you plot the points accurately. Once you have plotted all of the points, connect them with lines to create a visual representation of how the data is related.
Draw a line of best fit if desired.
Points are plotted on the graph based on the values of both variables for each data point. A line of best fit can be drawn if desired, which is a line that minimizes the sum of the squared distances from each point to the line. This line will not always be statistically significant, but it can provide a general idea of how the two variables are related.
What types of relationships can be observed in a scatter plot?
Four different types of relationships can be observed in a scatter diagram:
1. Linear Relationship
A linear relationship is a straight line pattern that indicates a strong correlation between the two variables. The points will be clustered near a line that runs through the middle of the points.
2. Quadratic Relationship
A quadratic relationship is a curved line pattern that indicates a moderate correlation between the two variables. The points will be clustered near a curved line that runs through the middle of the points.
3. No Relationship
A scatter diagram with no relationship will have points that are scattered randomly throughout the plane.
4. Positive Relationship
A positive relationship is a pattern where the points increase as you move along the x-axis. This indicates that the value of the first variable is increasing as the value of the second variable increases.
Overall, scatter diagrams are an important tool for data analysis because they help visualize relationships between variables. By creating a scatter diagram, you can quickly see if there is a correlation between the two variables and identify any outliers. This information can then be used to make better decisions about how to proceed with your data.