Sports and Events

The visualizations below explore the participation and performance of countries and athletes in Sports and Events in the Olympic Games from 1896 to 2016. Using interactive bar charts, bidirectionally linked line charts, and density-bar chart combinations, the data is analyzed to understand trends in participation by country, athlete demographics by gender over time, and the age distribution of medalists. The visualizations are interactive, allowing users to select specific sports, filter by gender, track country participation over time, and compare athlete demographics across sports.

• Which sports and events have experienced the most significant increase or decrease in country participation over the years?
• How has participation in different sports evolved over time based on gender, and are there specific sports where the gender gap has widened or narrowed?
• Are there any sports or events that exhibit a notable age gap between medalists?

These bidirectionally linked line charts show the participation trends in the top 5 sports by NOC and their associated top 3 events. The user can select the sport using the drop-down below and analyse the trends in both the plots. They are horizontally connected, making a view that allows easy comparison. Also, the bidirectional linking allows users to explore connections between sports and their events, ensuring deeper insights into participation changes.

This plot tracks the number of male and female participants in the top 10 sports across the years, allowing users to see if gender representation has become more balanced. By using bars and colour encoding for gender, it highlights sports with increasing or decreasing participation gaps over time. The interactive legend allows users to view trends by gender.

The density plot reveals the distribution of medalists' ages, helping a user analyse whether a certain sport has younger or older athletes winning medals. Users can select any one of the top 10 sports using the drop-down option. The bar chart horizontally added to this view shows the total medal counts per age group (binned), making it easy to figure out which age groups dominate in different events. Lately, the interactive radio button allows users to filter by medal type and focus the analysis on only one medal type at a time.

Tasks Supported

The visualizations above support the following tasks by utilizing interactive bar charts, bidirectionally linked line charts, and density-bar chart combinations, allowing users to dynamically explore sports participation by country, athlete demographics by gender over time, and age distribution for medal winners:

• Analyze Participation Trends: Identifying how athlete participation in different sports has evolved over time, with a focus on gender distribution and changes in representation.
• Track Country Participation: Exploring how many countries have competed in top sports and events over the years.
• Compare Growth in Sports & Events: Identifying which sports and events have gained or lost country participation over time, with bidirectional linking to focus on specific years.
• Examine Athlete Age Distributions: Analyzing the age range of medalists across different sports, identifying which events favor younger or older athletes.
• Interactive Filtering for Deeper Insights: Users can select specific sports, events, gender or medal types, to refine their analysis, enabling a focused exploration of trends and comparisons.

Visualization Design Justification

Bidirectionally Linked Line Charts

• Mark: The mark type used is a line (path) to represent the number of participating countries in different sports/events over time in both the line charts linked together by bidirectional linking. The Line mark indicates how the relationship evolves over time, showing increases, decreases, or reversals.


• Channels: Horizontal Position & Order: Represents years in an increasing sequence.
  Vertical Position: Represents the number of participating countries in a sport/event.
  Color Hue: Color Hue: Represents different sports/events, distinguishing participation trends.


• Characteristics of Channels: Different colors of the lines ensure the differentiation and easy following of the lines. The ordering of years follows a natural chronological sequence, helping in comprehension.


• Interactivity: Using the dropdown selection, users can select a specific sport, which inadvertently affects the events plot too, displaying the top 3 events associated with that sport. Hovering over the event plot displays its title, year, and NOC count. Bidirectional linking connects the trends of sports and their corresponding top 3 events, allowing users to see how participation has evolved. It allows users to highlight a time range and view corresponding trends in both graphs.


• Critique: Some sports/events may have small fluctuations, making it difficult to see trends without zooming in. A normalization option (e.g., showing percentage growth instead of raw numbers) could make comparisons clearer.

Bar Chart with Interactive Legend and Dropdown

• Mark: The mark type used are bars representing the number of participants in the top 10 sports over the years, with separate colours for male (light blue) and female (pink) participants.


• Channels: Horizontal Position & Order: Represents the years from the start of the Olympics to the present (1986-2016).
  Vertical Position & Order: Represents the number of participants (count) in a given sport.
  Color Hue: Represents gender (male or female) with distinct colours light blue and pink.


• Characteristics of Channels: The left-to-right order of years follows a naturally ordered reading flow, making trends easy to follow. The vertical axis uses an ordered scale, allowing for a straightforward comparison of participation trends through the height of the bars. The colour hue channel ensures that male and female participation trends are visually distinct. Stacked or grouped bars allow direct comparisons within the same sport.


• Interactivity: A drop-down menu allows users to filter participation trends by sport. It allows users to select and view trends in any of the 10 sports. Hovering over a bar displays a tooltip showing the exact sport, sex, count of IDs, and year through the use of a tooltip. An interactive legend allows users to view the bars only for male or female athletes by clicking on the legend. This allows for a more clearer understanding of trends by gender.


• Critique: Stacked bars can make it difficult to compare male and female participation directly since both bars don’t share a common baseline. But the interactive legend helps with this, allowing to single view per gender. Some sports have fluctuating participation, making trends difficult to interpret at a glance. If bars are too close together, it may be difficult to distinguish year-by-year trends. The colour choices for gender should be distinct enough to prevent confusion, especially in grayscale or colorblind-friendly modes.

Density Plot & Bar Chart (Age Distribution of Medalists)

• Mark: The mark type used is a Density plot to represent the distribution of ages among medalists. A bar chart is overlaid to show the total counts of medalists in different age groups.


• Channels: Horizontal Position & Order (Density Plot & Bar Chart): Represents the age of athletes. For the density plot, this shows how age is distributed, while in the bar chart, it corresponds to the age bins (e.g., 0-10, 10-20, 20-30 etc).
  Vertical Position (Density Plot): Represents the density of medalists of different ages.
  Vertical Position (Bar Chart): This represents the total count of medalists in each age bin.


• Characteristics of Channels: The Density plot allows for visualizing distributions, making it easier to see where the majority (most density) of medalists fall in terms of age. The bar chart provides a quick overview of age bins, giving an easier way to compare total counts. The scale of the density and bar chart changes according to the selected medal type and sport.


• Interactivity: The dropdown selection allows users to filter by sport, helping focus on a specific sport at once. Hovering over the Density plot reveals tooltips with precise information about age distributions and density. In the case of the bar chart it gives precise age and count of records. A radio button for medal selection allows users to toggle between viewing and filtering for a specific medal type (None for no medal win, Bronze, Silver, and Gold). The color associated with each medal type also clarifies comparison.


• Critique: The Density plot might be difficult to interpret for users unfamiliar with density estimation and just in general it is not easily interpretable at first glance. The lack of color hue might make it harder to recognize medal categories immediately, but the radio button ensures clarity by showing one medal type at a time. Comparing different medals requires switching between selections rather than seeing them side by side or stacked on top of each other.