The Data Visualization Competition is an important part of the China Visualization and Visual Analytics Conference. The competition invites researchers, developers, and enthusiasts to use their most effective visualization and visual analytics techniques/tools to accomplish data analysis as well as visualization tasks. The competition aims to help researchers, developers, and enthusiasts evaluate the effectiveness, novelty, and artistry of their techniques and tools in solving complex problems, and to promote the development and advancement of research and applications related to visualization and visual analytics in China.

At present, China's air pollution prevention and control are effective, thanks to the country's gradually increasing air quality monitoring network. In recent years, air quality monitoring stations have collected a large amount of air quality data with high-dimensional and time-series characteristics. It is very challenging to use such data to understand air pollution transmission patterns and provide effective suggestions for decision-makers. The use of big data analysis techniques and visualization methods can analyze air pollution problems and causes, monitor air pollution development trends, analyze the geographical relevance of air pollution, quickly perceive the time-varying patterns of air pollution, and assist staff to develop prevention and control strategies according to local conditions. Big data visual analysis and visualization combine data intelligent processing, visual representation, and interactive analysis organically so that machine intelligence and human wisdom can deeply integrate and complement each other, providing effective means and decision basis for analysis, command, and decision of air pollution prevention and control. The 8th China Visualization and Visual Analytics Conference Data Visualization Competition solicits relevant data visualization analysis and artistic visualization works from relevant researchers, university teachers, and students, enterprises, and data visualization analysis enthusiasts, and artists.

Entries are required to use the 2013-2018 China High-Resolution Air Pollution Reanalysis Open Data Set (http://naq.cicidata.top:10443/chinavis/opendata) provided by the competition to explore and discover the hidden patterns and laws behind the air quality big data using visual analysis techniques and visualization methods. The data is a nationwide database based on the data of the air quality. The data is a nationwide geospatial grid-based air quality reanalysis data and corresponding meteorological data covering 13 attributes including six conventional pollutants, wind speed, temperature, barometric pressure, relative humidity, and latitude and longitude (for detailed data descriptions, please visit the Open Data Set website). The data visualization competition is divided into two tracks.

（1）Data Visual Analysis Challenge track, in which participants can choose, but are not limited to, the following topics.

（2）Visualization Art track, the theme is "The Air We Breathe". Please move to Topic 2 of the Art Competition Call for Entries(http://chinavisap.net/comp-call-for-entries-en.html) for specific requirements.

The visualization competition is divided into two tracks under the same data framework: the Visual Analytics Challenge track and the Art track. The requirements and entry instructions for the Art Track are based on the Art Competition Call for Entries, which will be judged by the Art Program. The following are the instructions for the Visual Analytics Challenge track.

Teachers, students, and researchers from general higher education institutions (including higher education) and research institutes, developers and designers from enterprises and institutions, as well as visualization and visual analytics enthusiasts and artists are welcome to participate in the competition. Each team can consist of up to 5 participants, and the student team can have 1-2 instructors.

The first ranked participant of each team is the team leader and is responsible for communication. The team naming rule is: "Captain's first legal entity name - Captain's name", non-research institutes, enterprises, and institutions, etc. Please fill in the name of "enthusiast team" (enthusiast team means that the participant is a team formed as an individual). For example: "Tianjin University - Zhang San", "enthusiast team - Li Si".

The competition is open for online registration, the registration portal:https://s99x45wjic.jiandaoyun.com/f/604dcd76f95af00007f82707

The content of the work submission includes (1) work description document; (2) video; (3) representative pictures of the work. Please click on the submission portal to submit your works, and try to avoid submitting works during the peak period of the deadline.

Submission portal (will open on May 6):https://s99x45wjic.jiandaoyun.com/f/604dcd85c81ed0000726b572

Requirements for submission items:

All entries will be submitted to both visual analysis experts, domain experts, and visualization-related artists for comprehensive evaluation. The evaluation will focus on evaluating the thematic orientation and application value of the entries, as well as the effectiveness, novelty and artistry of the entries in terms of interaction design, degree of open data utilization, social benefits, analytical ideas and methods, etc.

Entries submitted by all eligible teams by the event deadline will be judged. The competition organizers will not evaluate any entries submitted after the deadline, and the organizers will not be held responsible for any damage, missing entries, or delayed submissions due to computer, Internet, or mobile network failures.

The chairman of the competition committee will select the first prize, second prize, third prize, excellent prize, or a small number of individual prizes in proportion to the results of expert evaluation. At the ChinaVis 2021 conference, award certificates will be presented to all winning teams, and some of the winning teams will be invited to make on-site presentations at the competition session of the conference.

1) Entries must not violate relevant national laws and regulations, and must not infringe on any third party intellectual property rights or other rights. If the work gives rise to intellectual property objections and disputes, the responsibility shall be borne by the participant.

2) Participants may use open source or commercial data analysis and visualization software, such as DataV、TableaU、R and Excel, etc. Participants are encouraged to use software development tools to design and implement their own visual analysis solutions or artistic visualization works. Common visualization development tools include D3、ECharts、AntV and Processing, etc. Participants are requested to clearly state the development tools used and the open-source or commercial software used in the documentation of the work.

3) The winning team must have at least one person registered with ChinaVis 2021.

4) Winning teams are required to make their entries into posters and participate in the poster session of ChinaVis 2021, with specific requirements referring to the poster session.

5) The intellectual property rights of the entries belong to the participants. The organizers of the conference have the right to use the entries, work-related materials, and team information for promotional materials, authorized media releases, official website browsing and downloading, exhibitions (including roving exhibitions), and other activities.

6) The air pollution dataset used in this visualization competition is the Chinese high-resolution air pollution reanalysis open dataset released by the Institute of Atmospheric Physics of the Chinese Academy of Sciences and other units. All the chairmen of the organizing committee of the 8th Data Visualization Competition sincerely thank the Institute of Atmospheric Physics of the Chinese Academy of Sciences for their great support! Welcome more researchers, developers, and enthusiasts for their continuous attention and support!