Measuring Engagement of Spectators of Social Digital Games

The purpose of this protocol is to enable the measurement of engagement of participants of a social digital game. This method combines physiological and self-reported data. As this game is social and therefore involves a group of people that move, the experiment is filmed in order to synchronize physiological data with events in the game.

This is the material needed to perform the protocol. We will refer to the boxes as EDA Box, the box used to record the EDA of the participant. Light box, the box with digital numbers.

And sync box, the box that sends signals to the EDA box and the light boxes to synchronize data. We also need two armbands, EDA electrodes, EDA sensors, medical tape, and antiseptic wipes. Plug the EDA boxes, the three light boxes, and the sync box into the charging station.

Place the consent forms, the pre-experimental questionnaire, and the jerseys on a table in the greeting area. Then, test the Bluetooth connection on the light boxes. Set the sync box to manual.

Turn on the three light boxes. Turn on the two EDA boxes. Turn on the Bluetooth on the EDA boxes.

Turn on the sync box and then push the pulse button on the sync box. The light box should flash the number one. Then, set the sync box and light boxes in place for the collection.

Place the light boxes in view of each camera. Put the sync box on the tripod at a height of six feet and set it to auto. Place the camera in order for the framing to include all four extremities of the game's playing field and the light box.

Greet the participants at the front door. Tell them to go sit at the table. Once all the participants have arrived and are seated, describe the tools which will be used to collect data for the present study.

This description should be written in the consent form. Then, tell the two randomly chosen participants to follow you to install the EDA equipment. During that time, the other participants can start to fill the pre-experiment questionnaire.

On the non-dominant hand, ask the participant to remove any jewelry. Use an antiseptic wipe to clean the area where the electrodes will be placed. Remove the electrode from the plastic and place them on the hand of the participant.

Then, snap the two sensors on the two electrodes. The red wire must be placed on the thumb side. The black wire must be placed on the other side, under the pinky finger.

Plug the sensor wire to the A3 port of the EDA box. Ask the participant if they tend to have sweaty palms. If they say that they do, wrap medical tape around the electrodes without touching the metal part.

Then add an arm band over the palm of the hand to secure the sensors and electrodes in place. Then turn on the EDA device. Check that the Bluetooth switch is still on.

Check that the four lights flash. Note the number of the participant and the number of the EDA box, then place the EDA box on their belt or in the pocket of the participant. Once all the participants have completed the pre-experimental questionnaire, walk them to the game studio, then record a base light.

To do so, tell the participants you need to calibrate your tools and ask them to breathe calmly and to fix something in front of their eyes for two minutes. Simultaneously, turn the EDA devices off and then on. Then start a timer for two minutes.

After the minutes end, turn the EDA device off and turn it on again. Start the recording of the three cameras and turn on the three light boxes. Also verify that the light boxes and the full playing field are still within the camera frame.

Verify that the sync box is on auto and turn on the sync box. Explain the game. Tell them that they game is similar to ping-pong and that they will understand while playing.

To win, one player needs to make three points. Also tell them that some members of the public will use their smartphones to influence the game by visiting the website URL that is projected on the playground. Then tell them who will take the role of player and who will be on the sidelines as spectators.

Announce which spectator will be using their smartphone for this game. While the participants are playing, visually check that the lights are flashing every 10 seconds. In between each game, ask participants to fill in the self assessment mannequin scale questionnaire on their smartphone, on an URL.

Give them the link of the questionnaire. Ask the participant to give you the box. Turn off the device.

Turn off the Bluetooth of the device, unplug the sensor from the A3 port and then remove the arm band. Unsnap the sensors from the electrodes and ask the participant to remove the medical tape and electrodes on their hand. Give the participants a tissue to remove the cream in the hand.

Then, remove the mini SD card from the EDA box and do the same with the second EDA participant. When it's over, ask the participants with EDA to fill in the end of experience questionnaire, too. Then debrief the participants.

Once they finish, thank them for their participation, tell them the goals of their research and their compensation. Then walk them out. After disassembling and putting away the data collection materials, transfer to physiological data on the computer.

Put the mini SD card from the EDA box in the adapter. Transfer the data to the computer in a folder named by the number of the participant. Verify the data is valid.

Select the data and put it in a spreadsheet. Hide the columns that are not useful. Select approximately one to 3000 and make a scatterplot.

If the data is between 240 and 550, the data is valid. Then verify if the markers generated by the sync box are present by selecting the event column and by sorting it. Sometimes there are markers that didn't appear.

This is not a problem. With only one marker, you can calculate the beginnings and ends of your events. Press control Z to put back the markers where they are.

Prepare the data for analysis. Add an event_start_end column. Watch the footage and when there is the beginning of an event, calculate the difference between the time of the event and the last marker.

When you find the seconds related to the event start, add a marker named event1_start. Do the same for the end of the event. Then repeat these steps for the baseline.

When you are finished adding the markers, export the spreadsheet in text file. You will have two per participant, one with the data and one with the baseline. Then, import these files into software.

This will generate a file ready for analysis that contains the relative time, absolute time, events, and EDA signal. Please note that the software is still in its early versions. Some of the icons may be missing.

I will guide you through the steps to get the physiological data file ready for analysis. Click on add project. Add a title.

Add a description. Enter the dates of the project and the total number of participants. Click on the name of the project.

Click on experimental design. Click on signals and choose physiological, EDA, blue box recorder, blue box, version three. Click on events and enter the events as they were previously named in the spreadsheet.

Choose blue box, version three. Click on transformations. Choose GSR, which refers to galvanic skin response or EDA.

Click unlocked to lock your project. Click on file import to import the files previously prepared. Click on the profile of the participant to give information about the participants by entering their email addresses.

Click on participant is there. Click on OK complete. Upload the data file, which needs to be zipped in order for the software to recognize it.

Click on the arrow. Click on the pies to upload the file. Go to analysis and choose data exportation.

Select the participant and their data. Click on export data to have a file ready for analysis. This can take hours, if you have many participants.

The file will appear under file name at the end of the exportation. Use the file generated for physiological data analysis. Here's an example of the file extracted from the software.

It is organized according to the starts and ends of events. It is all ready to be analyzed. The results found that perceived arousal, measured with the self assessment mannequin scale, and the physiological arousal, measured with EDA, were higher when the spectators had access to their smartphone to influence the game, which in turn, increased their engagement.

These results showed that this method provides the necessary data to evaluate engagement when mediated by physiological, as well as self-reported arousal. To conclude, in the context of digital games that do not take place within a screen, this method is adequate. We can video capture the action that takes place during the game while also being able to associate these actions to EDA variations.

Due to its portable equipment, this method could be used outside of the laboratory setting. It could be recreated in the real context of the game, which is a public space, in our case. Future development of the EDA device could also support other measurements, such as electrocardiogram, which will require another sensor and two other electrodes, accelerometer, and geolocalization.

These developments could allow the more precise assessment of the bodily reactions as well as movements in the context of games.