Reading all of the debate about the offensive line and the running game, I decided to do some research about the matter. I looked at the 2013 and 2014 YPC and adjusted them against the opponents YPC allowed. I also looked at sacks allowed, and compared them to the opponents average.
Note: I used YPC as a way to control for tempo, and it helps to find a common link between each game. For reference, I added the opponents rushing YPC rank along the y-axis. They are chronological-- CMU is the top and KSU is the bottom of 2013, and App State is the top for 2014.
To start with, I looked at Michigan's total YPC against each team. I then took this number and subtracted each opponents YPC allowed. I outputted this information into a graph, below. Values above 0 are good, values below 0 are bad.
The previous graph shows that out of our 13 games, we rushed better than the opponents average 6 times, and worse 7 times. However, only 2 times did we rush over 1 YPC more than the opponents average. On the flipside, 5 teams held us to 1 YPC less than their average or worse, with 2 teams obliterating us. It appears, IMO, that UCONN found our weakness and other teams after were able to capitalize.
Additionally, Minnesota (at 90th) and Indiana (at 117th) were poor run defense that shut us down. The final 2 games are a bit surprising. OSU can be chalked up to a rivalry game, or so I thought, but even with our backup QB we rushed decently against KSU (though only on 15 attempts).
The following graph shows the same data, but for this year. Some caveats apply: Only 6 games played thus far, with a large portion against poor teams, for instance.
From here, we can see that 2 teams have done better against us than their average, but not by nearly as much as 2013. Additionally, we have done a better job against the defenses we should, and even have an above average performance against what appears to be a good run defending team (Utah).
These numbers are subject to change throughout the season, but there appears to be a window for at least some hope.
Next, I looked at sacks allowed by our OL. Again, I subtracted the defenses average sacks from this number (adjusting it by taking out sacks against us). I did this here to get a view of how we stacked up against their other opponents.
Note: I also did these same graphs without adjusting (by taking out our sacks), and the charts are still roughly the same. The numbers skew a bit, but the trend is still there. Also, the numbers along the y-axis are the opponents rank for sacks per game.
The following graph is from 2013. Here, numbers below 0 are considered good, and numbers above 0 are considered bad.
Similar to the YPC chart, we started better and finished better, but struggled hard in the middle. We gave up an above average amount of sacks against teams ranked 100 and 103, and our best performance was against a team ranked 48. It is understandable to give up some sacks to Nebraska (20), but the amount is concerning. UCONN was the 100th team, by the way, again suggesing that they exposed a huge weakness.
The 2014 chart is next. This is subject to change much more, as the competition and small sample size make a more complete picture.
Thus far, the line appears to actually be doing a much better job of avoiding sacks, compared with how the opponents are playing against other teams. This is even against the 1st and 8th best teams as far as average sacks go. Utah, for instance, is averaging 5.6 sacks per game against everyone, and we "held" them to 4. Rutgers is averaging 4, and we "held" them to 3. Notre Dame is the lone exception this time, and I would contend that is more a product of having the lead that they did and didn't have to worry about us running nearly as much.
And lastly, I looked at a combination of the above. I took the sacks out of the rushing stats, and recalculated both our YPC and the opponents YPCA. The 2013 graph is shown below.
This actually looks worse to me. Now, we only have 4 performances above the average, and one just barely.
The 2014 one is next:
Here instead, we are now below average only once. Our rutgers performance is a bit weaker now, as is Utah, but the other performances are better than in the previous graph.
You are free to draw your own conclusions from these. There is obviously a lot more football to be played, but the early numbers are looking decent. We are running better against better defenses, and actually performing better than average against a couple aggressive defenses. I think the sacks above average might start getting closer to 0 as we move into conference play, but that will be something to keep an eye on.
If you have any suggestions, comments, criticism, etc., please feel free to share. If there is interest, I will try and update this post as the season continues (assuming I have the time to do so).
UPDATE: I have added in a similar analysis using sack percentage. Thank you for the suggestion. I have also done an analysis on YPC, and sack % after the first 6 games from last year as a comparison.
The first graph is for the 2013 sack percentage above average. Negative numbers are good while positive numbers are bad.
As you can see, we still have 6 good performances and 7 poor performances. Unfortunately, all games against an opponent worse than 100 we did poor against. And again, it looks like we had some flaws exposed, but this time it suggests we might actually have done something at the end to fix them. Whether that is scheme, or players just producing and developing, I cannot say.
The numbers so far for 2014 are shown now.
Here, we see that our Rutgers performance was worse than the first analysis shows, and the Minnesota numbers become average. I'm not worried about the average Minnesota numbers because it was just one sack. The Rutgers number scares me a bit more, but if you look at the context I'm not sure it should. We were playing a night game on the road, like against ND. This time, though, we allowed just one sack in the second half, and that was on our opening drive of the 2nd half. Yes, we don't want to give up 3 sacks on those few passing attempts, but just throughout the game we saw some improvement IMO.
Next, I looked at the sack percentage from 2013, but looked at just how our first 6 opponents faired in their first 6 games.
We can see from this that the trends stay mostly in line, surprisingly. The CMU game and the Akron games look better here than they end up, and the UCONN game looks worse. The other games stay about where they are.
Finally, I did the same YPC analysis above, where I took out sacks, and looked at the first 6 games.
What we see is that the first 2 games look better here (CMU and ND), as do the last 2 (Minnesota and PSU). The middle two stayed roughly the same. The game against ND shifted by about 1.25 YPC. I think that this shows that this isn't quite as good as it looked initially, but I don't want to make any sweeping conclusions here.
I wanted to add that I used data from cfbstats.com, and I got the rankings from teamrankings.com.