Visualizing WNBA history

Yesterday, at FiveThirtyEight, I waded into the discussion about a gender gap in basketball analytics with a report on the scarcity and fragility of data in women’s college basketball. I received a lot of comments about how the lack of public data in women’s basketball, both college and the NBA, is a reflection of a lack of demand. The argument was that if there was an audience for the data than leagues and media companies would provide it for their fans and customers.

Frankly, I think that perception is backwards. An increase in data sparks curiosity and drives demand. There was a (relatively) enormous amount of data available about men’s basketball long before there was any significant audience for it. Nylon Calculus has grown by leaps and bounds over the past two years but our traffic infinitesimal compared to the broader universe of basketball media. Even now, the NBA provides infrastructure and hosting for things like the SportVU player tracking statistics. I would guesstimate that a relatively small percentage of NBA fans are even aware of these statistics, let alone seek them out for their own purposes. The league and SportVU are presenting the data because they are hoping it will develop an audience, not because there is a loud and vociferous audience already calling for it.

For whatever reason, we have not seen the same effect on the women’s side. I would imagine there is a funneling effect, if you’re interested in basketball data you’ll migrate to where it already exists. Whereas, ten years ago it didn’t exist for either gender so people set about creating it from scratch. It would be nice if the WNBA (perhaps with some help from the NBA), the NCAA, or some private for-profit companies developed a broader infrastructure for women’s data but I think it is just as important for curious people to write about it and share resources they build themselves. Putting my money where my mouth is, I woke up this morning and built two quick visualizations using historic WNBA data from Basketball-Reference.com. This first one shows all players from all seasons in the league’s history, and their progression of Win Shares.

I thought this was a particularly interesting view because it lets you explore the evolution of the league, specifically the stars who have driven it. For example, look at this filtered view showing the career progressions for Cynthia Cooper, Sheryl Swoopes, Tamika Catchings, Candace Parker (the pink line), and Maya Moore.

You can see how the productivity of each player has risen and fallen, overlapping in places as one star hands off top dog role to another. The WNBA is heading into its 20th season, there is a rich history here to explore, many great players to remember and reflect on.

This second visualization is something we look at frequently on the men’s side — the relationship between usage and efficiency. The graph shows all players from all seasons by each measure, filtered here to just seasons with at least 250 minutes played.

Filter it down to the same handful of stars we looked at above and you can see how Cooper’s brilliance continues to define the outer boundaries of usage and efficiency at the WNBA level.

There is nothing ground-breaking in these graphs, it’s a look at WNBA history with fairly straight-forward data that can all be found at Basketball-Reference. Hopefully it sparks some curiosity in someone else out there to roll the ball a little further, ask some questions, share a few more answers.