If you’re a business user of any of the major self-service business intelligence tools, the chances are that you’ve found yourself staring at the dashboard as the systems asks you to define what the dimension is and what the measure is. Perhaps you’ve tried to think back to high school math class: is the dimension the Y axis and the measure the X, or is it the other way around?
The truth is that you are not alone in your confusion. When Qlik, Tableau and others use the term dimension and measure, they are simplifying as much as possible the mathematics behind their solutions. How else can these companies ask you to tell the computer this critical information? The system needs to know what data to present on which part of the chart, and these terms are the best way to ask this in a non-technical way. However, this doesn’t mean that the terms aren’t confusing, because they are. So what is a dimension and a measure?
What is a Dimension?
A dimension is the lens through which you are looking at your data. It is the way you “categorize” the data. The most common dimension is, arguably, time. For example, if I am looking at sales by month in 2015, then the dimension is the months of the year 2015. However, you can categorize data in non-chronological ways as well: for example, if I am looking at GDP by country, then the dimension is country.
The dimension adds context to your measure and helps you to better understand what your data means.
What is a Measure?
The measure is the easy part. This is the numerical values that quantify the data set that you are digging into to understand better. So if you are looking at sales by employee, then “sales” is the measure and employees are the dimension.
Can you Have Multiple Dimensions?
I am not referring to the multiple dimensions from Sci-Fi or physics, but from a strictly data analysis angle. It is entirely possible to look at data through different dimensions at the same time. The best way to explain is through an example: perhaps you want to look at GDP by country over the last 30 years, then the last 30 years and the countries are both the dimensions, so in that scenario you have two dimensions and one measure.
Whether you are generating a graph with Qlik or a narrative with Savvy, you can finally be perfectly clear on what the difference is between a measure and a dimension. Interested in learning more about the evolution of business analytics? Download this infographic.