Why scatter diagram is used

Features Visual Designer. Flipbook Maker New. Chart Maker. Form Builder. Background Remover. Diagram Creator. Photo Book Maker New.

Collage Maker. Spreadsheet Editor. Data Widgets. Photos Effects. Visual Paradigm Desktop. Photo Books. Knowledge What is a Scatter Diagram? What is a Scatter Diagram? Edit this Diagram Most often a scatter diagram is used to prove or disprove cause-and-effect relationships. Scatter Diagram Correlation Patterns The degree to which the variables are related to each other depends on how the points are scattered over the chart. Complex Correlation The value of Y seems to be related to the value of X, but the relationship is not easily determined.

About Scatter Diagram. Scatter Diagram Resources. Scatter Diagram Related Topics. What is a Scatter Diagram?

Quality Glossary Definition: Scatter diagram Also called: scatter plot, X-Y graph The scatter diagram graphs pairs of numerical data, with one variable on each axis, to look for a relationship between them. When to use a scatter diagram Scatter diagram procedure Scatter diagram example Scatter diagram considerations Scatter diagram resources When to Use a Scatter Diagram When you have paired numerical data When your dependent variable may have multiple values for each value of your independent variable When trying to determine whether the two variables are related, such as: When trying to identify potential root causes of problems After brainstorming causes and effects using a fishbone diagram to determine objectively whether a particular cause and effect are related When determining whether two effects that appear to be related both occur with the same cause When testing for autocorrelation before constructing a control chart Scatter Diagram Procedure Collect pairs of data where a relationship is suspected.

Draw a graph with the independent variable on the horizontal axis and the dependent variable on the vertical axis. For each pair of data, put a dot or a symbol where the x-axis value intersects the y-axis value.

If two dots fall together, put them side by side, touching, so that you can see both. Look at the pattern of points to see if a relationship is obvious. If the data clearly form a line or a curve, you may stop because variables are correlated. You may wish to use regression or correlation analysis now. Otherwise, complete steps 4 through 7. Divide points on the graph into four quadrants. If number of points is odd, draw the line through the middle point.

Count the points in each quadrant. Do not count points on a line. Add the diagonally opposite quadrants. Find the smaller sum and the total of points in all quadrants.

No correlation on the other hand does not mean there is no cause-and-effect relationship. There might be a relationship over a wider range of data or a different portion of the range. The following is an analysis that shows the relationship between the volume and the diameter of sample trees in a forest see sample data. The scatter diagram suggests that the two variables are correlated.

The following is an analysis that was conducted for diagnosing the presence of diabetes at a workplace see sample data. The population was generally young The scatter diagram suggests that there is no obvious relationship between age and glucose levels. High glucose levels are found in all ages, and normal glucose levels are found in higher ages. A Matrix Plot is used to summarize the relationship between pairs of multiple variables in one graph. It produces a scatter diagram for every combination of variables.

Potential correlations between pairs of variables can then be identified. In the following matrix plot, it appears that there is a positive relationship between the years of experience and salaries. However, the number of publications does not appear to be correlated with the years of experience. Question: Is there a correlation between the number of publication and salaries? There are many tools that allow to draw a scatter diagram.

One of the simplest ways is to use this scatter diagram template. By the CIToolkit content team 4 minutes read. How to Construct a Scatter Diagram You must first collect the two paired sets of data. Once you have collected enough data points, create a summary table of the data.