Guide for Attendees

General information

GECCO’21 will be hosted in two virtual platforms, Whova and Gather. All talks (sessions, keynotes, workshops and other events involving oral presentations) will be streamed in Whova. Gather will be used for coffee breaks, poster sessions and other interactive events. Both platforms run in-browser and will be cross-linked to facilitate moving between them. Each registered participant will receive email with credentials shortly before the conference.

While Whova provides a convenient static view of the event and structured access to schedule and content (days, sessions, tracks, talks, etc.), Gather is a game-like environment where each participant controls a mobile customizable avatar that can interact with other participants face-to-face via video chats and in other ways. Our Gather map will emulate a virtual conference center and its surroundings, featuring spacious foyer, lecture rooms, info desks, exhibitions, drawing tables for technical discussions, and other facilities, including renderings of the landmarks of the beautiful city of Lille, France, the host of the conference.

To connect better with other participants and so improve the experience, we strongly encourage all attendees to spend most of their time between sessions in Gather, interacting with other participants, visiting exhibitions and exploring the environment. Sessions and other talks will be accessible from Gather too, i.e. interacting with a ‘session object’ will open the corresponding page in Whova. The platform will be running 24/7 for the entire conference period, so it can be enjoyed also from the less conveniently located time zones. See our promotional video, Gather demos and instructions for more details. If you have no prior experience with Gather, consider familiarizing yourself with the platform prior to the event.

To sum up, as a general rule, we ask the participants to spend most of their time during oral sessions in Whova, and most of the remaining time in Gather.

Our video streaming platform behind Whova is Zoom. Neither Zoom, Gather, nor Whova require dedicated software on your device. Whova offers a mature mobile app that has been praised by many users. Gather offers also a standalone application, though it’s still in beta.

Please note: While most of the guidelines provided below are universal, there are slight differences (marked in the text) in how they apply to conference talks and workshop talks.

Guidelines for all attendees

  • Always use headphones to avoid echos and parasitic feedback.
  • Pick a quiet space for giving your presentation or asking questions, to avoid disturbing background noise.
  • Chats are actually great for asking questions without interrupting the speaker, let’s make use of the chat provided in Whova.
  • You can ask questions in the chat during the talk; however, the speakers are free to choose to either answer them on the spot, or wait until the end of the talk.
  • Please keep the following in mind that, in online events, the attention span of the audience tends to be shorter than in onsite events — this was one of the motivations for shortening the talks in this edition of GECCO — we kindly ask you to make an extra effort to stimulate interactions.
  • Coffee breaks will be longer than usual, allowing for a lot of one-to-one interaction in Gather.
  • Adhere to the ACM's Policy Against Harassment, as requested during registration.

Guidelines for preparing your oral presentations

  • For conference presentations only: Please note that at this year’s oral presentation slots are only 20 minutes long, of which at least 4 minutes should be left for discussion. It is thus recommended to rehearse your talk to fit into 16 minutes.
  • For Hot Off the Press presentations: The oral presentation slots will be 10 minutes long, with 7 minutes for the presentation and 3 minutes for questions.
  • For Student Workshop presentations: The oral presentation slots will be 20 minutes long, with 16 minutes for the presentation and 4 minutes for questions.
  • For workshop talks, presentation length may vary; you will receive instructions from the workshop organizers.
  • Make an extra effort to engage the audience and sustain its attention.
  • Focus on conveying the essence of your contribution, leaving out the inessential details. Saying less, but clearly is preferable to rushing through a lot of content.
  • Avoid verbosity on your visual material: prefer short phrases to full sentences, and use no more than 5-6 of them on each slide. Remember that most people are bad at multitasking, which implies they tend to either listen to you or read your slides, but rarely both.
  • Try not to read directly from the slides or notes that you write for yourself, notes are great for practice, but a natural live presentation is so much better, even if not as smooth.
  • If you have equations or result graphs on slides, ensure that you explain them and do not rush through.
  • Do not assume that everyone in the audience knows all the concepts, make a judgement on what needs to be introduced based on the track and session that you are in — a 30 seconds introduction often saves a lot of frustration for someone less familiar with the topic of your work.
  • Ensure that the font size is readable (without zooming in) even at the HD resolution (1280×720 pixels).

Guidelines for speakers

  • All talks should be given live — pre-recorded videos are meant only as a backup, to be used sparingly in case of serious technical difficulties.
  • Enter your Whova session at least 15 minutes before the scheduled presentation/poster session time to check the equipment and screen sharing.
  • Enable your camera whenever possible, to connect better to your audience and improve listeners’ experience. As much as possible, have your camera at eye level and look into the camera when talking. Try and have an uncluttered background or use built-in functionality to blur your natural background or apply a professional looking background.
  • Avoid quick flipping of slides – viewers with slower connections may experience significant lags. If you plan to play a video clip, consider slowing it down, for the same reason.
  • Once the session is over, presenters are strongly encouraged to join their session room in Gather for additional questions and (informal) discussions about their talk.
  • Be ready to reply to (offline) questions that may arise in Whova after your talk.

Guidelines for poster presenters

  • The list of posters and maps for poster room 1 and poster room 2 are downloadable.
  • Be prepared that some participants will spend 1 minute looking at your poster, others 5 mins and some others 15+ minutes.
  • Instead of trying to include every single detail of the work on the poster, think about the three groups above, and how you can create a poster from which everyone takes home something useful. Spend time on deciding what to exclude from the full paper rather than meticulously including every detail.
  • Ensure that the poster clearly presents the key take-home message.
  • Think of what is the best visual way of illustrating this.
  • Use colours that are contrasting.
  • If your paper contains very large tables or result graphs, consider just showing parts of these, or the key information instead of the full detail.
  • You can include a QR code that links to your paper online, so any interested visitor can take a picture and go directly to the paper.
  • Decide on a logical and simple structure for the poster, so that a viewer can figure out how to read it even if you are not there to explain.
  • Remember that the poster is expected to attract attention and spark a discussion, and not to be a replica of the paper.

Technical instructions for posters

  • Prepare your poster in landscape orientation (16:9) with a minimum width of 1000 pixels, in PNG or JPG file format and a maximum size of 3MB.
  • Provide a thumbnail version of your poster in PNG or JPG with a minimum width of 600 pixels and a maximum size of 1.5 MB.
  • The main poster and the thumbnail shall be uploaded, together with the 5-minute video summary using the GECCO submission system.

Technical instructions for pre-recorded video presentations

  • Recall that pre-recorded videos are meant only as a backup, to be used sparingly in case of serious technical difficulties — all talks should be given live.
  • For conference presentations only: Video presentations for full papers should not be longer than 16 minutes.
  • For Hot Off the Press presentations only: Video presentations for Hot Off the Press contributions should not be longer than 7 minutes.
  • Video summaries for posters (including Late Breaking Abstracts) should not be longer than 5 minutes.
  • Prepare your video in MP4 file format.
  • Video presentations shall be uploaded using the GECCO submission system.

Video Recording & Editing Software

There exist several options to record and edit your presentation and you may choose the one you are most familiar with. If this is your first time, we suggest the following options:

  • If you already use Zoom for video conferencing, you can launch a Zoom meeting just for yourself and use the Share screen and Record features to easily record your presentation.
  • If you are looking for recording software, we suggest OBS Studio, a multi-platform open source solution, for which you will find many tutorials online.
  • Once recorded, you may wish to edit your video. MacOS users may want to try iMovie. For a multi-platform open source solution, we suggest OpenShot.

Guidelines for session chairs

  • Arrive at your session early, at least 15 minutes before the scheduled start, to ensure speakers have checked in, and have everything they need for their presentation. If time permits, check if they can share their screens.
  • A volunteer will be connected to the session and available to assist you.
  • During the session, make sure that attendees are muted, and that only speakers can share their screen and use annotations.
  • In the unlikely event that a speaker faces technical issues, play the pre-recorded video of his/her presentation. The speaker should attend the session in order to answer questions. In the unlikely event that a speaker is absent in the Q&A part of the talk, announce a break until the next presentation is due to start.
  • Do not start early, as participants may be moving between sessions/presentations.
  • Introduce each speaker.
  • For conference presentations only: Speakers are allocated 20 minutes for a presentation: 16 minutes for set up and presentation, and 4 minutes for questions. Make sure the speakers adhere to the maximum time allotted.
  • During the talk, the audience is allowed to ask questions in the chat; however, the speakers are free to choose to either answer them on the spot, or wait until the end of the talk. In the latter case, you may allow the speaker to answer the questions in the chat alone, or help him/her at that by reading the questions out loud. However, if there are other (oral) questions from the audience during discussion, we recommend to intertwine them with those from the chat, in order to engage the audience.
  • Moderate the Q&A session and manage the Q&A chat. If there are no questions, ask one yourself (time permitting). Do not start the next presentation early (or late).
  • Let the conference organizers know of any problems or if adjustments are needed. Prevent accidental unmuting, disruptive screen sharing, or offensive behavior from the audience. Report serious cases of any such behavior to the organizers.
  • Ensure that the schedule is respected by the speakers and that the session ends timely. Follow the scheduled order of talks, as well as presentation times.
  • Once the session is over, announce the time available before for the next slot, and invite the audience to convene in the session room in Gather for additional questions and informal discussion.