## Thursday, January 24, 2019

### 2018 Yards Per Play: ACC

We are now into the third week of our offseason recap and we move to our second conference and home of the current national champion, the ACC.

Here are the ACC standings.
So we know what each team achieved, but how did they perform? To answer that, here are the Yards Per Play (YPP), Yards Per Play Allowed (YPA) and Net Yards Per Play (Net) numbers for each ACC team. This includes conference play only, with the championship game not included. The teams are sorted by division by Net YPP with conference rank in parentheses.
College football teams play either eight or nine conference games. Consequently, their record in such a small sample may not be indicative of their quality of play. A few fortuitous bounces here or there can be the difference between another ho-hum campaign or a special season. Randomness and other factors outside of our perception play a role in determining the standings. It would be fantastic if college football teams played 100 or even 1000 games. Then we could have a better idea about which teams were really the best. Alas, players would miss too much class time, their bodies would be battered beyond recognition, and I would never leave the couch. As it is, we have to make do with the handful of games teams do play. In those games, we can learn a lot from a team’s YPP. Since 2005, I have collected YPP data for every conference. I use conference games only because teams play such divergent non-conference schedules and the teams within a conference tend to be of similar quality. By running a regression analysis between a team’s Net YPP (the difference between their Yards Per Play and Yards Per Play Allowed) and their conference winning percentage, we can see if Net YPP is a decent predictor of a team’s record. Spoiler alert. It is. For the statistically inclined, the correlation coefficient between a team’s Net YPP in conference play and their conference record is around .66. Since Net YPP is a solid predictor of a team’s conference record, we can use it to identify which teams had a significant disparity between their conference record as predicted by Net YPP and their actual conference record. I used a difference of .200 between predicted and actual winning percentage as the threshold for ‘significant’. Why .200? It is a little arbitrary, but .200 corresponds to a difference of 1.6 games over an eight game conference schedule and 1.8 games over a nine game one. Over or under-performing by more than a game and a half in a small sample seems significant to me. In the 2018 season, which teams in the ACC met this threshold? Here are ACC teams sorted by performance over what would be expected from their Net YPP numbers.
The ACC saw a pair of teams significantly over-perform relative to their expected records (Syracuse and Georgia Tech) and one team significantly under-perform (North Carolina). In addition, four other teams (Florida State, Miami, NC State, and Virginia Tech) nearly met the threshold for under or over-performance. Syracuse’s conference record was buoyed by their league-leading in-conference turnover margin of +11 while Georgia Tech was second at +7. The Yellow Jackets also posted a solid, but not extreme 2-1 mark in close games. Meanwhile, North Carolina managed a 1-4 mark in close conference games, losing a pair in overtime (Syracuse and NC State). In addition, six of North Carolina’s seven conference losses came by ten points or fewer.

Worst Over First
Speaking of North Carolina, back on September 22nd, the Tar Heels beat the Pitt Panthers in their conference opener to improve to 1-2 on the young season and provide a modicum of hope for their beleaguered fan base. The loss dropped Pitt to 2-2 overall (1-1 in the ACC) and the game seemed destined for the dustbin of history. There was nothing really remarkable about North Carolina’s victory at the time. And then the rest of the season played out. North Carolina lost their last seven conference games, with their only victory post-Pitt coming against an FCS opponent the weekend before Thanksgiving. Meanwhile, Pitt won five conference games in a row and thanks to poor play by the presumptive division favorite, the Panthers had the division locked up the time they traveled to Coral Gables over Thanksgiving weekend. The victory by the Tar Heels meant the worst team in the division (by record) had beaten the division champion. How often has this happened in a BCS or Power Five conference? The answer: Not very, and the ACC has been involved in most of them. The table below lists those occurrences, and since it has only happened eight times including North Carolina's win in 2018, I’ll regale you with some background on each.

November 5th, 2005
NC State 20 Florida State 15
Florida State entered this game 7-1 overall and 5-1 in the ACC. NC State was 3-4 (1-4 in the ACC) and fighting for their bowl lives. Befitting a 20-15 final score, the quarterback play was horrid with Marcus Stone, Drew Weatherford, and Xavier Lee combing for 269 passing yards on 62 attempts. NC State lost to Boston College the next week, but won their last two games to finish bowl eligible. They won the prestigious Meineke Car Care Bowl in Charlotte after the regular season. Florida State lost their next two games following their home loss to the Wolfpack, losing the Bowden Bowl to Clemson and the annual rivalry game with Florida (in Urban Meyer’s first season as coach) before upsetting Virginia Tech in the inaugural ACC Championship Game. The Seminoles closed the year losing a tight Orange Bowl to Penn State in a battle of old ass head coaches who would go on to ruin their legacies by supporting Donald Trump and abetting a child molester (its an open question which is worse). While NC State finished tied for last in the Atlantic Division of the ACC, their 3-5 record was only two games worse than Florida State’s.

November 10th, 2007
Maryland 42 Boston College 35
In a wild and crazy college football season, Boston College had been ranked second in the country the week before, but an upset home loss to Florida State dropped them to number eight. Maryland entered the game 4-5 (1-4 in the ACC), having lost three in a row. The Terps led by 21 entering the fourth quarter and the final score was not indicative of the quality of the game as Boston College scored with under a minute left to cut the lead to seven. Maryland split their next two games to finish bowl eligible while Boston College won their last two games to clinch a rematch with Virginia Tech in the ACC Championship Game. The Eagles lost to the Hokies and had to settle for a Champs Sports Bowl appearance.

November 1st, 2008
Clemson 27 Boston College 21
In a wide-open ACC Atlantic, Boston College entered this game 5-2 overall (2-2 in the ACC). Clemson was a preseason top-ten team, but the Tigers entered on a three-game losing streak. This marked just the second game as head coach for Dabo Swinney (whatever happened to him?) who replaced Tommy Bowden following a loss to Wake Forest. Clemson scored ten points in the final eight minutes to give Dabo his first win as Clemson head coach. Clemson would lose to Florida State the following week, but win their final three regular season games to salvage a bowl bid and get Dabo the full time job. Boston College rebounded from the loss to win their final four regular season games and earn another shot at Virginia Tech. The Eagles would lose to the Hokies once again and have to settle for a Music City Bowl bid. 2008 was a weird year for the ACC with eleven of the twelve conference teams finishing within one game of .500 in league play, so Clemson only finished a game behind the Eagles, but were technically tied for last in the division.

October 3rd, 2009
Maryland 24 Clemson 21
The first full season of the Dabo Swinney era saw Clemson lose a pair of tight early season contests to ranked teams (Georgia Tech and TCU). The Tigers headed to Maryland with a 2-2 record (1-1 in the ACC) to face a team that was 1-3. The Terps had been blown out by Cal and Rutgers while also losing to Middle Tennessee State. Their lone win had come against James Madison of the FCS. But the Terps played their best game of the season by far against the Tigers, scoring three straight touchdowns in the second and third quarters to lead by eleven. CJ Spiller ran a kickoff back in the third quarter to cut the lead to three, but Clemson missed a field goal late in the fourth and Maryland held on. Maryland would use the momentum generated by this upset to lose their final seven conference games. Meanwhile, Clemson won six in a row following this defeat to set up a rematch with Georgia Tech in the ACC Championship Game which they also lost.

October 16th, 2010