Location section in the dashboard allows you to investigate the location data provided by participants during your study. Note that Location section is only available if you have chosen GPS stream during your study design.
There are two types of visualizations available for GPS data: you can either plot the trajectory or the heatmap of the visits for a given participant during a specific time window. Each of these plots are described below.
Note that the plots presented here is only to provide a quick way to investigate the uploaded data, and it does not utilize all data uploaded for GPS stream. You can check all data available on GPS stream section. Also the plots in this section filter data with accuracy of less than 100 meters.
As of now there is no automated method to download GPS data. If you need to access raw GPS data, you can contact us and we will provide you with the raw GPS data in the format you need.
Temporal GPS Plot
You can plot the GPS data uploaded by a particular participant over time, to visualize the trajectory of the given participant in that specified time window. For this purpose, you can select Participant and Duration, and set the Overlay to Temporal. In the following screenshot we are requesting the GPS trajectory for participant #231 during May 21st 2016:
Pressing Go will plot the GPS data uploaded by participant #231 during May 21st. Here we assume there has been data uploaded by the participant at the specified time window. You can validate this through Compliance section.
Pressing Go will plot the full trajectory during this time window, as shown in the image below. Notice that there is a slider now added below the control overlay which its bar is moved to the right end. Below this slider you can see the last time any data was uploaded by the participant during this time window.
You can move the slider to change the time. The screen capture below shows moving the slider to the left side follows the trajectory backwards, while moving it to the right side follows it forward.
You can plot the heatmap for the GPS data uploaded by a participant at a specific time window. This is similar to Temporal GPS Plot, and you only need to select Heatmap as Overlay. For example, the following plot shows the heatmap of places visited during the month of December 2015 by user #231:
The heatmap plot is calculated by first drawing a grid on the map where each is is 11.12 meters in latitude and 6.821 meters in longitude. Then the algorithm counts the number of GPS readings which indicated the participant to be in any of these cells. For example, if the participant has been in a given cell for 5 hours, and during this 5 hours Ethica recorded total of 600 GPS records (10 GPS records for each 5-minute interval), the intensity in the heatmap for that cell will be equal to 600.