Alyson M. Downing

Kelsey F. Chisholm

Paul M. Sommers

English

Research Papers in Economics

                                                                                                                                             
 
 
MOVING BACK THE NCAA’S THREE-POINT LINE: 
A CHALLENGE? 
 
 
by 
 
Paul M. Sommers 
Kelsey F. Chisholm 
And 
Alyson M. Downing 
 
 
 
 
 
March  2010 
 
 
 
 
 
MIDDLEBURY COLLEGE ECONOMICS DISCUSSION PAPER NO. 10-21 
 
 
 
 
 
 
 
 
DEPARTMENT OF ECONOMICS 
MIDDLEBURY COLLEGE 
MIDDLEBURY, VERMONT 05753 
 
http://www.middlebury.edu/~econ 
 
 
 
                                                                                                                                               
 
2
 
 
 
 
 
 
 
 
 
MOVING BACK THE NCAA’S THREE-POINT LINE: 
A CHALLENGE? 
 
 
 
 
by 
 
 
 
 
Kelsey F. Chisholm 
Alyson M. Downing 
Paul M. Sommers 
 
 
 
 
 
 
 
Department of Economics 
Middlebury College 
Middlebury, Vermont 05753 
psommers@middlebury.edu                                                                                                                                               
 
3
 
 
MOVING BACK THE NCAA’S THREE-POINT LINE: 
A CHALLENGE? 
 
 
 
  In an effort to spread defenses in men’s basketball and rejuvenate post play (nearest to 
the basket), the NCAA decided in May 2007 to move the men’s three-point line back a foot to a 
new distance of 20 feet, 9 inches.  Did the additional twelve inches present a challenge for 
Division I teams?  Did teams not only take fewer three-point shots, but did the new line adversely 
affect shooting percentages?   
  In this brief note, we examine the difference in the average number of three-point field 
goal attempts (hereafter, 3PTFGA) and the percentage of three-pointers made from behind the 
new arch (hereafter, PCT) between 2008-09 (one season after the change) and 2007-08 (one 
season before).  All data are from www.ncaa.com/sports/m-baskbl/stats/ for all Division I men’s 
basketball teams that made a minimum of five three-point field goals per game both seasons.  
There were observations on a total of 280 Division-I men’s basketball programs.
1  We also made 
before-and-after comparisons for eight conferences: Atlantic Coast Conference (hereafter, ACC); 
Big East; Big Ten; Big 12; PAC-10; Southeastern Conference (SEC); Western Athletic 
Conference (WAC); and Conference USA.  Finally, we compared three-point field goal attempts 
and the percentage of three-pointers made for two elite groups of schools: the “Sweet 16” from 
the 2007-08 NCAA Tournament and the “Sweet 16” from the 2008-09 Tournament.
2 
  The results of a series of paired t-tests are reported in Table 1.  For all 280 schools, the 
average number of three-pointers attempted (p = .015) and the average percentage made (p = .001) 
dropped in the season following the change.  By contrast, for the eight conferences (accounting 
for about one-third of the Division I teams in our sample), the differences were few.  The PAC-10 
with the highest three-point shooting percentage (of the eight conferences examined here) before 
the change (36.1 percent) connected on the highest percentage of three-pointers (36.9 percent)                                                                                                                                               
 
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after the change.  Of note, the shooting percentage fell in the Big East (p = .008) and the number 
of three-pointers attempted fell in the WAC (p = .028).
3,4  Among elite schools (namely, the 
“Sweet 16” in each NCAA Tournament, the year before and after the change), there were no 
statistically significant differences. 
 
Concluding Remarks 
 
  In 2007, the NCAA voted to move the three-point line in men’s basketball one additional 
foot away from the basket.  The new three-point distance became effective at the start of the 
2008-09 season.  For all Division I teams in our sample, the number of three-point shots 
attempted fell, on average, about 2.1 percent and the percentage of three-pointers made fell less 
than one percent (from 35.3 percent to 34.6 percent).  For conferences that have sent 
disproportionately many teams to the season-ending “March Madness” tournament, the 
movement of the three-point line has neither deterred long-range shooters nor adversely affected 
their shooting percentage.  Deep shooters (especially from elite programs) have adjusted quite 
well to stepping a foot back.                                                                                                                                               
 
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Table 1.    Paired t-Test Results 
on 3-Pointers Attempted and Made, 
for Selected Conferences 
between 2007-08 and 2008-09 
 
 
                                                                               
                                                                                                                                       p-value
* 
                          2007-08 averages
a                   2008-09 averages                 on difference 
                                                                                                                                           2007-08 and 2008-09 
 
                      3PTFG     3PTFGA    PCT           3PTFG     3PTFGA    PCT           3PTFGA     PCT   
  
 
All schools 
 (n = 280)  221.535 626.189  .353  212.796 612.986  .346  .015  .001 
 
Selected 
conferences 
 
ACC (n = 12)  218.917 613.417  .356  202.583 585.917  .344  .215  .054 
 
Big East (n = 16)  221.813 630.875  .350  218.438 649.438  .333  .834  .008 
 
Big Ten (n = 11)  225.545 648.182  .349  228.818 646.455  .354  .480  .743 
 
Big 12 (n = 12)  223.333 632.083  .353  234.167 652.583  .358  .696  .722 
 
PAC-10 (n = 10)  213.400 591.500  .361  213.600 576.300  .369  .285  .715 
 
SEC (n = 12)  241.833 681.667  .354  224.583 648.500  .346  .173  .198 
 
WAC (n = 9)  203.889 571.667  .355  184.000 528.333  .345  .028 .214 
 
Conference USA 
     (n = 12)  217.750 629.833  .341  197.583 582.417  .338  .164  .413 
 
Sweet 16 
 2007-08  255.375 697.000  .367  237.313 661.375  .359  .109  .125 
 
Sweet 16 
 2008-09  236.438 651.688  .363  238.750 663.313  .360  .687  .282 
 
 
*p-values are for a one-tailed alternative that the average for 2008-09 is smaller than the  
 corresponding average for 2007-08. 
aThe average PCT reported here for the paired t-tests is equal to the sum of the PCTs across 
 all n schools divided by n; it is not the average PCT found by summing 3PTFG across all n 
 schools and then dividing this sum by the sum of the 3PTFGAs across all n schools.                                                                                                                                               
 
6
 
Footnotes 
 
 
1.  There were initially 265 Division I schools common to both NCAA lists, one each 
  season, with a minimum of 5.0 three-point field goals made per game.  In some instances, 
  a school was listed one year, but not the other.  To include all members of the eight  
  selected conferences, we needed to add observations (both years) on fifteen more 
  teams (from the respective school’s men’s basketball Web site):  Wake Forest (ACC); 
  Connecticut, St. John’s and USF (Big East); Michigan State (Big Ten); Texas (Big 12); 
Washington and USC (PAC-10); Alabama (SEC); Nevada, Hawaii and San Jose State 
(WAC); and Tulane, Southern Mississippi and Rice (Conference USA). 
 
2.  Seven schools advanced to their respective regional semifinals both seasons: Kansas, 
  Louisville, Memphis, Michigan State, North Carolina, Villanova, and Xavier. 
 
3.  The Big East includes the following schools: Cincinnati, Connecticut, DePaul, 
  Georgetown, Louisville, Marquette, Notre Dame, Pittsburgh, Providence, Rutgers, 
  Seton Hall, St. John’s, Syracuse, USF, Villanova, and West Virginia. 
 
4.  The WAC includes the following schools: Boise State, Fresno State, Hawaii, Idaho, 
  Louisiana Tech, Nevada, New Mexico State, San Jose State, and Utah State.  
 

Moving Back the NCAA’s Three-point Line: A Challenge?

http://www.middlebury.edu/services/econ/repec/mdl/ancoec/1021.pdf

Moving Back the NCAA’s Three-point Line: A Challenge?

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