Thursday, December 14, 2006

On Sport Popularity and Patents

Google Patents allows us to search the entire patent database. My "discovery" comes on the heels of the UTA Department of Economics seminar last Friday given by Yi Deng of SMU. Prof Deng is looking at patent data in the context of knowledge spillovers. She revealed (and colleague Mike Ward agreed) that while the patent data are freely available they are not yet easy to work with. However, as the patent data becomes more democratically available, I think we will see a lot of interesting research in the next few years.

While I was goofing off with Google Patents, I happened to search for NASCAR. It turns out there are 189 patents that contain the word NASCAR. This got me searching for patents containing other sports - I started with the big ones like baseball, swimming, and so forth. My expectation was that more popular sports by definition have larger potential and actual markets (by number of people if not by amount of money), and should attract more innovation in the form of new patents. Things seemed to follow that general pattern but the ocular estimator is notoriously misleading. I moved to a more "sophisticated" statistical test with the goal of spending ten minutes or less.

I gathered sport participation rates at the National Sporting Goods Association (four minutes), looked up the exact sports titles in Google Patents, and recorded the number of patents found (five minutes). I threw the data into STATA and here's the list ordered by total patents (part = percentage of people over 7 that participated in the sport in 2005)

     +-----------------------------------------------+
     |                       sport   patents    part |
     |-----------------------------------------------|
  1. |                Cheerleading        18     3.3 |
  2. |               Muzzleloading        51     4.1 |
  3. |   Target Shooting  - Airgun        82     6.7 |
  4. |             Workout at Club       119    34.7 |
  5. |            Kayaking/Rafting       190     7.6 |
     |-----------------------------------------------|
  6. |             Paintball Games       261       8 |
  7. |  Mountain Biking (off road)       288     9.2 |
  8. |    Backpack/Wilderness Camp       456    13.3 |
  9. |               Skateboarding       495      12 |
 10. |      In-Line Roller Skating       513    13.1 |
     |-----------------------------------------------|
 11. |                      Soccer       525    14.1 |
 12. |             Running/Jogging       552    29.2 |
 13. |             Skiing (alpine)       628     6.9 |
 14. |      Skiing (cross country)       629     1.9 |
 15. |                Snowboarding       632       6 |
     |-----------------------------------------------|
 16. |          Aerobic Exercising       637    33.7 |
 17. |                  Volleyball       641    13.2 |
 18. |                    Softball       664    14.1 |
 19. | Camping (vacation/overnite)       665      46 |
 20. |                Water Skiing       673     6.7 |
     |-----------------------------------------------|
 21. |              Billiards/Pool       676    37.3 |
 22. |                      Hiking       690    29.8 |
 23. |        Boating, Motor/Power       695    27.5 |
 24. |   Exercising with Equipment       695    54.2 |
 25. |              Scooter Riding       765    10.4 |
     |-----------------------------------------------|
 26. |             Target Shooting       830    21.9 |
 27. |                Hockey (ice)       889     2.4 |
 28. |            Archery (target)       891     6.8 |
 29. |                  Basketball       911    29.9 |
 30. |       Hunting w/Bow & Arrow       913     6.6 |
     |-----------------------------------------------|
 31. |           Football (tackle)       949     9.9 |
 32. |                      Tennis      1002    11.1 |
 33. |                    Baseball      1004    14.6 |
 34. |                     Bowling      1010    45.4 |
 35. |                    Swimming      1048      58 |
     |-----------------------------------------------|
 36. |       Hunting with Firearms      1056    19.4 |
 37. |            Exercise Walking      1130      86 |
 38. |                     Fishing      1149    43.3 |
 39. |              Bicycle Riding      1151    43.1 |
 40. |               Weightlifting      1164    35.5 |
     |-----------------------------------------------|
 41. |                        Golf      1181    24.7 |
     +-----------------------------------------------+

We were a litte past the the ten minute mark at this point, so I just calculated the Spearman Rank correlation coefficient between the number of patents and total participation rates:

. spearman total patents

 Number of obs =      41
Spearman's rho =       0.4893

Test of Ho: total and patents are independent
    Prob > |t| =       0.0012

At the eleven minute mark I had a (not so sophisticated) test of the hypothesis. The evidence suggests a positive and statistically significant relationship between a sport's popularity and the number of patents that contain that sport's name. Whew.

Carry on.