Introduction

Coaching changes in NCAAF often bring a mix of hope and uncertainty. Whether it's a new head coach or a fresh coordinator, these shifts can significantly alter a team's trajectory. But how often do these changes lead to the desired outcomes? Let's delve into the numbers and trends to understand the real impact of coaching changes on offensive and defensive performance.

The Role of SP+ Projections

SP+ projections have been a reliable tool for predicting team performance in NCAAF. Last season, five of the top six teams in the preseason SP+ projections made the College Football Playoff. However, these projections don't account for coaching changes, which can have a profound effect on a team's performance.

Head Coaching Changes

When a team changes its head coach, the impact can be substantial. Over the past 15 years, there's a strong negative correlation (-0.559) between a team's previous-year performance and its subsequent SP+ rating change. This means that teams that overachieved last year and lost their head coach are likely to regress, while those that underachieved and changed coaches are likely to improve.

Teams Likely to Improve

• Southern Miss Golden Eagles: After a dismal 1-11 season, Southern Miss hired Charles Huff, who could bring a much-needed turnaround.
• Tulsa Golden Hurricane: With Tre Lamb at the helm, Tulsa is expected to rise from their 3-9 record.
• Purdue Boilermakers: Barry Odom's arrival could help Purdue rebound from a 1-11 season.

Teams Likely to Regress

• UNLV Rebels: Despite hiring Dan Mullen, UNLV's historic overachievement last season suggests a potential regression.
• Bowling Green Falcons: With Scot Loeffler's departure, Bowling Green might struggle to maintain their 7-6 record.

Offensive Coordinator Changes

Changing offensive coordinators can be just as impactful as changing head coaches. The correlation between recent performance and next season's performance is nearly as strong (-0.509) for offensive coordinator changes.

Teams Likely to Improve

• Oklahoma Sooners: After a poor offensive showing, Oklahoma brought in Ben Arbuckle to revitalize their offense.
• Houston Cougars: Slade Nagle's return could help Houston recover from their offensive collapse.

Teams Likely to Regress

• Texas State Bobcats: After overachieving last season, Texas State might see a dip in offensive performance.

Defensive Coordinator Changes

Defensive coordinator changes also follow a similar pattern, though the correlation (-0.468) is slightly weaker.

Teams Likely to Improve

• San Diego State Aztecs: Rob Aurich's arrival could help SDSU rebound from a poor defensive season.
• Oklahoma State Cowboys: Todd Grantham's experience might improve OSU's defense.

Teams Likely to Regress

• Northern Illinois Huskies: Losing Nick Benedetto could lead to a defensive decline.

Conclusion

Coaching changes in NCAAF can bring both opportunities and challenges. While some teams may see significant improvements, others might experience regression. Understanding these trends can provide valuable insights for fans and analysts alike.