Scatter plots are often used to identify any correlation or observe relationships between two variables. By looking at these plots, the reader can quickly observe any trends, if present. A scatter plot is a very useful tool in any analyst's toolbox.
For this recipe, let's use the sample file Sample – Superstore Sales (Excel)
. Open a new worksheet and select Sample – Superstore Sales (Excel) as the data source.
Once the data is loaded, perform the following steps to create a scatter plot of two measures:
By default, Tableau will aggregate measures to show only the aggregated values. In traditional statistics, however, to observe any trends or correlation between two variables, individual data points are plotted across both axes. Therefore, we removed the aggregation for this recipe, but please note that some applications of scatter plots may warrant aggregation.
Scatter plots are one of the most common techniques to observe the relationship between two variables. It is important to note, however, that a plot may suggest a correlation between two variables but cannot conclusively prove a causal relationship. You can read more about scatter plots on the National Institute of Standards and Technology (NIST) exploratory data analysis handbook at http://www.itl.nist.gov/div898/handbook/eda/section3/scatterp.htm.