This story appears in ESPN The Magazine's September 18 NFL Preview Issue. Subscribe today!

Since 2005, the winningest teams at home -- Boise State and Ohio State, Oklahoma and Alabama -- win the most on the road too. So how's a 12th man supposed to know that he makes a difference?

Forget win-loss results. The real measure of home-field advantage lies in performance, so we examined how every FBS team fared, scoreboard-wise, in every home game in the past 12 seasons. Then we compared those numbers to the Football Power Index* expected margin of victory in those contests. Take last year's Week 5 Stanford-Washington clash in Seattle. According to FPI, the Huskies were expected to win by 14.7 points but won in a stunning 44-6 romp. U-Dub's 23.3-point swing -- or points above expectation (PAE) -- is our metric proxy for home-field performance. Win by more than anticipated? Lose by less? PAE's got you covered, telling you the tale of just how much your team exceeds (or falls short of) expectations.

So take heed, Mississippi State. Let your guard down in Week 2 at Louisiana Tech (No. 1 in PAE) and you might just find yourselves in the doghouse. Here's what else we learned.

*FPI is a predictive measure of team strength that represents how many points a team is above or below an average FBS team. For the purposes of this exercise, we use end-of-season FPI.

The few, the loud, the Bulldogs

In its 54 home games against FBS opponents since 2005, Louisiana Tech has performed 3.6 points per game better than expected -- making the Bulldogs the biggest overachievers at home in the nation. But where are the bluebloods, you ask? Wisconsin checks in at No. 7 (2.4 points above expectation) and Oklahoma at No. 13 (1.8), but largely, the top 25 teams in PAE are not your perennial powerhouses. Case in point: Among last season's four playoff punchers, only Clemson cracks the top 30. Florida State? At No. 96, the Noles' minus-1.3 points above expectation is right on par with noted in-state rival ... Florida Atlantic.

So apologies to the Big House (and all the other big houses); for an edge at home, it's not the size of the crowd in the fight. Since 2005, LaTech has averaged just 19,312 fans, and the crowds for the top five teams in PAE currently average 45,000. Meanwhile, Michigan (No. 43 in PAE) packed in 110,468 last season.

Top teams, PAE at home vs. FBS

Worst teams in each Power 5 conference, PAE at home vs. FBS

Don't see your team? Scroll down to check out the full PAE rankings.

A rising tide

When the going gets tough, Alabama gets tougher. The Crimson Tide rank a lowly 101st in points above expectation when factoring in all home games. Weed out FCS foes, though, and they inch up to No. 77. Narrow that down even further, to just in-conference competition? Nick Saban's crew leaps to 11th best in the country. In other words, as the competition gets better in Tuscaloosa, so does the Tide's edge. Sweet home Alabama, indeed.

The Tide don't roll alone, though. Like Alabama, Wisconsin ranks outside the top 10 in PAE at home against all competition -- though well ahead of Bama at No. 16. Still, the Badgers improve to No. 7 against FBS teams and climb all the way to No. 1 in conference play.

A few that don't rise to the occasion? Once-proud programs Nebraska and Miami, which rank 36th and 75th overall, plummet 47 and 29 spots, respectively, in conference outings at home.

Biggest PAE Differentials The Tide's PAE at home against all teams, FBS or FCS, since 2005 is minus-1.2. Against conference rivals? 2.2. That 3.4-point swing is the biggest such uptick in the FBS. Here is the full top five. Team PAE Diff. 1. Alabama 3.4 2. Wisconsin 2.9 3. Wake Forest 2.5 4. Ohio State 2.0 5. Northern Illinois 1.7

Stars come out at night

Reports of Death Valley have been greatly exaggerated.* LSU's Tiger Stadium, where former head coach Les Miles said opponents' dreams come to die, is actually downright hospitable! The Tigers have performed 0.5 points below expectation against FBS foes since 2005 (No. 72 nationally) and plunge even further into a home-field abyss against conference opponents: minus-2.1 PAE, No. 101. Among Power 5 teams, only notable home-field lame ducks Boston College, Miami, Purdue, Duke and Illinois fare worse against conference foes. Consider, in contrast, Baylor. In the Bears' final five seasons at Floyd Casey Stadium -- their home before McLane -- they performed 6.1 points above expectation vs. the FBS. Now, that's a graveyard of opponent dreams.

*With one major caveat. Turns out, day and night games in Death Valley are as different as ... night and day. In home tilts kicking off at 6 p.m. or later, the Tigers have performed 0.9 points above expectation against FBS opponents since 2005 -- a 1.4-point swing compared with its full slate.

Pass, happy

The adage that "defense travels" might be true if the Big 12's home PAE is any indication: 0.9, the highest of any conference. The league's high-flying offenses -- 33.6 ppg and 454.4 ypg since 2012, both FBS bests -- often pass roughshod over opposing defenses. And with visiting D's generally unable to stop offensive onslaughts, they also fail to quiet those buzzing Big 12 home crowds.

By comparison, every other Power 5 conference hovers around zero points above expectation ... except the Big Ten. Not only does it claim the worst Power 5 advantage at minus-0.7 PAE, four teams -- Maryland (No. 100), Northwestern (No. 109), Rutgers (No. 112) and Purdue (No. 118) -- rank in the triple digits nationally since 2005.

PAE by conference, at home vs. FBS (since 2012*)

*Conference analysis limited to the past five seasons due to realignment.

Road warriors

And then there are teams that seek the comfort of ... anywhere else. (See above: The Sun Belt registered minus-3.1 in PAE -- two points worse than any other league.) Still, no team enjoys a road advantage quite like Navy, which is a hefty 5.0 points per game better than expected in away contests since 2005.

So what's the Middies' secret? It may be as simple as X's and O's (or just O's). Over the past 12 years, no team averages more plays per drive than Navy and its triple-option offense (6.1) or bleeds the clock more (257 drives of five-plus minutes). The FBS's other triple-option attacks follow suit: Air Force, Army and Georgia Tech all rank top-11 in the FBS in plays per drive, top-seven in five-minute drives ... and top-30 in road PAE in that span. Road game, set, match.

PAE rankings, Teams 1-120

Points Above Expectation Team W-L PAE 1. Louisiana Tech 35-19 3.60 2. Kansas State 49-20 3.31 3. Colorado 29-35 2.93 4. Arizona State 45-24 2.73 5. Marshall 40-22 2.70 6. Iowa State 28-38 2.54 7. Wisconsin 63-10 2.39 8. Colorado State 30-29 2.31 9. Nevada 43-22 2.30 10. Cincinnati 39-15 2.19 11. Arizona 39-30 1.97 12. Baylor 38-25 1.84 13. Oklahoma 62-8 1.84 14. East Carolina 44-22 1.62 15. West Virginia 52-18 1.54 16. Arkansas State 45-12 1.51 17. Louisville 47-21 1.33 18. TCU 48-15 1.33 19. Kansas 31-35 1.27 20. UNLV 24-42 1.21 21. UTEP 33-32 1.21 22. Middle Tennessee 34-23 1.18 23. Oklahoma State 50-19 1.17 24. Connecticut 36-31 1.16 25. Houston 47-14 1.14 26. Clemson 57-14 1.11 27. Indiana 28-41 1.08 28. South Carolina 50-22 1.03 29. Arkansas 35-22 1.02 30. Northern Illinois 41-13 0.87 31. Ole Miss 36-34 0.85 32. Kentucky 35-38 0.75 33. Iowa 47-24 0.74 34. Texas Tech 38-23 0.72 35. Buffalo 23-36 0.71 36. Boise State 64-4 0.68 37. Nebraska 59-20 0.63 38. Texas A&M 44-28 0.52 39. Georgia Tech 43-24 0.51 40. San Diego State 41-24 0.48 41. Rice 36-27 0.42 42. Oregon State 37-29 0.40 43. Michigan 61-23 0.39 44. North Texas 21-40 0.35 45. New Mexico 28-40 0.33 46. Florida 57-13 0.33 47. Auburn 57-22 0.29 48. Georgia 50-16 0.25 49. North Carolina 41-25 0.23 50. Penn State 63-17 0.20 51. Oregon 58-13 0.20 52. UCLA 51-24 0.18 53. Temple 34-29 0.10 54. Air Force 40-22 0.08 55. Washington State 22-37 0.05 56. Virginia Tech 50-17 -0.04 57. Minnesota 38-34 -0.05 58. California 36-27 -0.07 59. Ohio 39-20 -0.13 60. Ohio State 75-8 -0.13 61. Mississippi State 34-33 -0.18 62. Utah 47-20 -0.19 63. UCF 42-26 -0.21 64. Brigham Young 52-12 -0.25 65. Central Michigan 30-25 -0.26 66. Southern Methodist 29-38 -0.27 67. USC 61-14 -0.30 68. San Jose State 27-30 -0.34 69. Wake Forest 33-35 -0.40 70. Boston College 39-28 -0.41 71. Wyoming 30-33 -0.44 72. LSU 65-12 -0.46 73. Western Michigan 33-21 -0.56 74. South Florida 33-30 -0.56 75. Toledo 41-22 -0.60 76. Syracuse 22-44 -0.65 77. Alabama 66-10 -0.68 78. Miami (OH) 23-37 -0.69 79. Washington 34-34 -0.71 80. North Carolina State 35-34 -0.72 81. Memphis 27-39 -0.75 82. Missouri 45-21 -0.77 83. Miami (FL) 44-23 -0.82 84. New Mexico State 13-51 -0.91 85. Michigan State 52-25 -0.97 86. Fresno State 36-26 -0.98 87. Western Kentucky 23-23 -1.01 88. Pittsburgh 41-28 -1.05 89. Troy 37-19 -1.09 90. Vanderbilt 27-41 -1.09 91. Utah State 32-28 -1.11 92. Illinois 28-40 -1.13 93. Florida International 22-35 -1.26 94. Virginia 34-37 -1.26 95. Tennessee 50-28 -1.26 96. Florida State 50-18 -1.29 97. Florida Atlantic 20-32 -1.30 98. Tulsa 44-23 -1.33 99. Idaho 18-39 -1.34 100. Maryland 28-37 -1.34 101. Army 17-34 -1.67 102. Tulane 17-42 -1.96 103. Stanford 51-23 -1.99 104. Texas 51-22 -2.01 105. Notre Dame 50-26 -2.01 106. Duke 21-45 -2.06 107. Southern Miss 32-29 -2.07 108. Kent State 20-35 -2.15 109. Northwestern 37-31 -2.15 110. Hawaii 35-33 -2.31 111. UAB 17-31 -2.31 112. Rutgers 36-31 -2.38 113. Ball State 26-29 -2.42 114. Bowling Green 28-30 -2.42 115. Navy 38-15 -2.48 116. Akron 21-38 -2.77 117. Louisiana-Monroe 24-25 -2.78 118. Purdue 29-44 -2.96 119. Eastern Michigan 13-40 -3.29 120. Louisiana-Lafayette 31-26 -4.35 Minimum 35 FBS home games since 2005

For more from ESPN Analytics, visit the ESPN Analytics Index.