Big Data, sound maps, and debate: The EVOTION project at People’s Democratic Festival

Eriksholm Research Centre and the EU project EVOTION were present at this year’s People’s Democratic Festival (Folkemødet) to demonstrate to the public what we can do with data.


One moment, you are sitting by the harbour, peacefully enjoying a cup of coffee while talking quietly with a friend. The next moment you are in a big crowd of people all talking simultaneously. And later, you listen to a speech held by a politician while people are mumbling next to you.

The sound environments of the People’s Democratic Festival (Folkemødet) are diverse and change in both volume and quality according to location, time of the day, and what happens around you. This can be displayed to people via data, which is what Eriksholm Research Centre and the EVOTION project did at this year’s festival.

EVOTION: A concrete example of Big Data research

The People’s Democratic Festival is a yearly event in Denmark packed with debates, talks, and a nice atmosphere, and it attracts both politicians, organizations, and the public.
This year, Eriksholm was present with the big EU funded project EVOTION in which we collaborate with several European research institutions to collect data from 1000+ test subjects to learn about user behavior. Read more about EVOTION here.

Data collection and how we can use sound data in research was the topics in our festival booth.

“I think a lot of citizens hear about Big Data in the media, but they don’t know what it is, how it looks, and what they can use it for. So we are bringing in EVOTION as a concrete example of what we can use data for,” Research Engineer on the EVOTION project Jeppe Høy Christensen explains.

Creating the sound map of the People’s Democratic Festival

We did this by getting volunteer citizens to collect data at the festival using EVOTION hearing aids connected to smartphones via Bluetooth – and then later show them their own ‘sound map’ of the festival.

In total, 19 citizens volunteered to collect sound data. You can see our sound maps of the festival below. Figure 1 shows the average sound that the citizens were exposed to, separated by time and sound 'characteristic'. Figure 2 shows the geographical distribution of the recorded sound data pooled from all participants.

We furthermore had three events discussing the use of data in health research, presenting the data from People's Democratic Festival, and talking about how research changes when data is collected in the test subjects’ everyday life rather than in the lab.

“From demonstrating EVOTION at this very large festival we hope to expose the challenges people with hearing loss have and what can be done in the future to make better hearing solutions,” says EVOTION project manager Niels Henrik Meedom.

According to Niels Henrik Meedom, the festival gave EVOTION a lot of important feedback on what people see as challenges and advantages of health data.

“It has been a very great experience,” he concludes.

  • folkemde2019-(002)
    Figure 2: The sound of Allinge during People's Democratic Festival 2019
    The sound level (dot color) is plotted at each GPS location in the data collected during a whole day (9am – 8pm) of People's Democratic Festival. The size of each dot represents the noise level: large dots indicates less noise – that is, a more clear sound. 
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    Figure 1: The sound of People's Democratic Festival 2019

    The sound level (x-axis) and noise level (y-axis) are derived from a factor analysis of a sound environment vector (five acoustical parameters) sampled every minute from the EVOTION hearing aids. The mean of the data recorded during People's Dmeocratic Festival (dots) are color-coded according to the time-of-day. The contour plots represent the sound of known environments. Prior to plotting, all data was scaled and centered with a common mean and SD.