Heat Maps is a simple yet powerful technique that leverages the human’s superior visual cognitive capacity to gain deeper and faster insights into data and information.
Cormac Kinney coined the term in 1991 to describe a 2D-display depicting real-time financial market information.
A heat map is any data visualization that uses color to represent data values in a two-dimensional image. A simple heat map provides an immediate visual summary of information. More elaborate heat maps allow the viewer to understand complex data sets.
There are many different types of heat maps used in different disciplines, each referred to by the term “heat map”, even though they use different visualization techniques.
The reason heat maps work so well is because of our ‘Pre-attentive Processing’ ability. The term refers to the ability of the low-level human visual system to rapidly identify properties, such as color and size, in less than 250 milliseconds.
According to Van der Heijden, we unconsciously accumulate information from the environment ,which is pre-attentively processed. The brain filters and processes what is important based on what stands out the most. Once the individual’s attention is captured (based on what is of relevance to what the individual is thinking), at that point the information is selected for further and more complete analysis by conscious (attentive) processing.
It is a two-stage process, which happens in seconds, and this is why heat maps are so powerful.
Heat maps are being used in many sectors and that is great. The best way to demonstrate these is to show you examples. I use some examples as shown by John Brandon in a slide presentation.
Marketing people created the map above. By using eye-tracking devices, a heat map is created showing where attention of the user is focused on display pages. The map above is a sample heat map of a Google search result.
A dominant pattern for search engine results is the “F” pattern showing the eye being drawn to the upper left (hot colors) and then moving down and across from there (shown as the blue colors). There are, however, factors (such as the inclusion of images, graphics, and additional columns) that can significantly alter this pattern.
This heat map displays risk by location. It was created by RMS (risk management company) to show risks related to catastrophic events: Earthquakes, hurricanes, severe storms (including tornados and hail), wind storms, wildfires and volcanoes. An insurance company might use it to determine the “probability of loss” related to such an event.
This heat map shows the reality of fraud attempts in real-time using live data. A red dot pops up to show a fraud attempt. ThreatMatrix culls the data from 1,950 customers, which includes about 9,000 websites, and tracks about 360,000 cyberattacks per day.
This heat map from MarketProphit shows buzz and sentiment around specific stocks. The larger blocks indicate the most buzz (or discussion) around a stock as culled from Twitter. The colors show sentiment; the red blocks denote negative comments and the green denotes positive comments. In an instant, financial planners can see general trends with stocks based on social media posts.
This heat map shows the movements of customers in a retail store aisle. Red areas represent the spots where most customers shop. Retailers can use the heat map for product placements and to see whether a sales campaign was successful.
This heat map shows the age of buildings in the Portland, Ore. area. About 544,000 structures are represented, including about 4,500 erected in the 1800s and 10,265 buildings constructed in 1978 alone.
Justin Palmer created this heat maps based on public data released by the City of Portland. It shows the age of buildings. This can help municipalities see which neighborhoods hold the greatest concentration of structures that may need repairs.
Click on the link (http://citysdk.waag.org/buildings/) to see the map in large scale, iit s beautiful. It shows the nearly 10 million buildings in the Netherlands; some in central Amsterdam are more than 1,000 years old.
Some would argue that heat maps are very specific – “the heat map is a treemap-like graphical technique used to represent a two-dimensional array of data” as shown in the example below.
Many techniques illustrated in this post, as argued by the purists, are not heat maps. I agree and I disagree. The principle of using color to very quickly highlight the issues of concern, attention or importance is extremely valuable and it is a perfect example of how we work better with visuals than with coded jargon. The fact that it is called a heat map – well, does it matter? Notionally, it is a perfect description even though it might not be as it was originally labeled – I think this is a good and natural evolution of the principles. I will call these techniques ‘heat maps’ – it works and it is powerful.