Our visualization aims to answer the question: How do top Spotify songs vary across different countries and time periods? With the interactive features implemented in this project, users can easily investigate which songs dominate Spotify charts in different locations over time. To provide an interactive way to explore global and regional music trends, we utilized an interactive 3D globe from the Globe Data Visualization library globe.gl where users can rotate, zoom, and select country markers to explore local music trends. We initially considered a traditional 2D map but found that it introduced overlapping markers in densely populated regions, making interactions cumbersome. A timeline-based visualization was another option, but it lacked the spatial representation necessary for comparing music trends between regions. All things considered, the 3D globe is the best choice, as it allows for intuitive exploration of trends and ensures that countries have enough space for interaction while maintaining a compelling design. A dropdown menu was chosen for selecting years and months due to its simplicity, intuitiveness, and compact design. This approach allows users to make selections quickly without taking up excessive screen space or extra effort. An alternative option was a slider, but it was not chosen because it made precise selection of months and years more difficult compared to the dropdown menu. Dropdown menu also allows users to make comparisons for the same month across different years easier than with a slider (can be useful to identify a theme across seasons, like for Christmas).

To provide users with an easy, intuitive exploration experience, we incorporated several interactive elements. Countries that share the same most-streamed song have the same color pin to make it easy to identify global hits at a glance. In early prototypes, we experimented with gradient shading to indicate varying popularity, but this led to visual ambiguity when multiple songs had similar distributions. Instead, distinct colors were chosen for clarity. Clicking a marker reveals a pop-up containing the top five songs for that country, along with streaming statistics. We initially considered using hover interactions but found they interfered with the globe’s rotation and made it difficult to compare multiple countries at once. Inside the pop-up, a bar chart compares local versus global stream counts. Our initial design used stacked bar charts, but proportions were harder to interpret, so we opted for separate bars with a stronger contrast between local (blue) and global (gray) streams. Another important consideration was whether to normalize the Y-axis across all countries. While this would allow for direct comparisons, it reduced readability for countries with lower streaming numbers. We ultimately chose individual scaling to ensure all data remained legible.

As a team we collectively spent roughly 24 hours on this project with each member contributing about 6 hours. We spent most of our time on ensuring that the design was intuitive and made for an enjoyable experience to interact with. One example of this is when we noticed it was difficult to scroll on our page, the globe's canvas would take priority over the scroll wheel event and trigger a zoom, we added space to either side of the globe that would allow for normal scrolling. We also scaled the globe down so that the majority of the rest of the page could fit on without any zoom at all. Downloading the data also took a considerable amount of time as spotify's site forbade scraping so we had to manually download each file. For more in detail of who was responsible for what, Raahil implemented the interactive globe and placed markers for each country that we added data on. Juliane processed the data and developed the pop-up feature that appears when a user clicks on a marker. Chon designed and implemented the navigation bar along with the dropdown menu. Lunjia completed the write-up which documented our design process.