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Archive for the 'AFL versus NFL' Category

AFL versus NFL: the power ratings

Posted by Jason Lisk on December 22, 2009

I could have handled the conclusions one of two ways. The first would have been to present all my conclusions and then have a chart of all the AFL and NFL teams from the decade with their ratings. The second way is to present the results first, and then follow up with how I got there. I opted for the second way, as I didn't want the results and actual team ratings to be a footnote at the end of the series. These ratings, after all, were the reason I started on this path in the first place. I wanted to see how an NFL team compared in 1964 to an AFL team, how the champions of each league compared, and so forth.

I don't claim that these numbers are completely accurate or infallible. There is simply year to year variation across leagues and teams that we can't measure accurately. How do the 2007 Colts compare to the 2009 Colts? We don't know, because they didn't play in the exact same situation, and that's with a lot more direct information to draw upon than what we have when comparing the AFL and NFL. We do have numbers upon which we can make reasonable estimates though. Similarly, these numbers represent my best available guess of how teams compared during the decade of the 1960's. If you've been following along and read the entire series up until now, you probably have some idea how I got there, but I'll explain in the final post how I settled on the best guesses that I did.

5 Comments | Posted in AFL versus NFL

AFL versus NFL: post merger results

Posted by Jason Lisk on December 15, 2009

This is the final piece of evidence before we get to the conclusions and overall team power rankings for the decade. Let's get right to it. Here are the point differentials and the win/loss records (from the perspective of the former NFL teams) for all regular season matchups involving an AFL team and a former NFL team from 1970-1974.

Year NFL AFL DIFF W L T WIN PCT
1970 21.5 15.6 5.9 39 19 2 0.667
1971 22.2 17.4 4.8 35 19 2 0.643
1972 21.1 17.6 3.5 33 26 1 0.558
1973 20.2 19.4 0.8 27 27 4 0.500
1974 18.8 21.4 -2.6 21 36 1 0.371

These results include matchups involving Pittsburgh, Cleveland and Baltimore against the AFC opponents. The AFL was not good relative to the NFL in 1970, the first season after the leagues merged. The next set of numbers are weighted by team quality. For example, Houston and Cincinnati played more games against former NFL teams than did Kansas City, Oakland, San Diego and Denver after the merger. Baltimore, Cleveland and Pittsburgh played more games against the AFL (by virtue of joining the AFC) than other NFL members. As Kansas City, Oakland and San Diego were three of the four best AFL teams in the late 1960's, and two teams that had been frequent playoff participants in the NFL were now joining the AFC, this might bias the results slightly in the NFL's favor.

Even considering this, though, the NFL dominated in 1970, and in fact, that year shows as more of an outlier than the raw numbers would indicate. This is because Baltimore and Cleveland show up as worse based on regular season SRS in 1970 (though Baltimore won the Super Bowl), and then they bounced back and Pittsburgh improved steadily over the next five years. Here are the schedule adjusted differentials between the teams from the two leagues during the first five years post-merger.

5 Comments | Posted in AFL versus NFL

AFL versus NFL: the Super Bowls, part two

Posted by Jason Lisk on December 9, 2009

Earlier in the series, I looked at how much we should take from the four Super Bowls, by looking at historical championship games, and how much the game results deviated from the team regular season ratings. I didn't want to actually discuss the specifics of the game until I had gone in depth on the other evidence. Now, it's time to turn back to those four Super Bowls, and the teams involved. I'll tell you right now that you can find a lot of resources that go very in depth on each of these games and teams, moreso than I have the knowledge or time to do here. I have no personal knowledge of these games, have only seen the highlights, and am going strictly off what I see from reconstructing the play by plays using our Super Bowl play finder.

It does, however, give me an excuse to give a sneak peak at the ratings I have for the AFL and NFL teams of the 1960's. You may have noticed that we added the Simple Rating System ratings to the team pages and standings going back to 1960. My ratings are going to differ slightly from those you see on those pages. My rating tweaks the simple rating system, similar to what Chase is doing with the college rankings. The primary changes between my ratings and what you see on the team pages are:

19 Comments | Posted in AFL versus NFL

AFL versus NFL: 1967-1969 draft and trends

Posted by Jason Lisk on October 1, 2009

This is the final draft class installment, looking at the players drafted in the common drafts of 1967-1969 after the two leagues had agreed to the merger. I'm going to include a breakdown of the NFL teams that moved to the AFC (Baltimore, Cleveland and Pittsburgh) and those that stayed in the NFC, as well as the AFL teams. These draft classes would have played most of their careers after the merger. Nevertheless, we will see that they did have an impact as the decade closed out. The pro bowl adjustments for the AFL guys should be virtually non-existent at this point, precisely because most of those pro bowls came after the merger.

I'm including the trends in this post as well, as the commentary on the draft classes will be more limited.

2 Comments | Posted in AFL versus NFL, NFL Draft

AFL versus NFL: the exhibition games

Posted by Jason Lisk on September 28, 2009

After the merger was announced in the summer of 1966, three primary things were set before the leagues would officially merge for the 1970 season. First, the champions of the two leagues would meet in an AFL-NFL championship game, beginning in the 1966 season. Second, the two leagues would conduct a joint college draft and no longer engage in bidding wars for players, beginning with the 1967 draft. Third, the two leagues would be free to schedule exhibition games, beginning with the 1967 pre-season (presumably because the merger agreement was finalized less than two months before the start of the exhibition games in 1966).

The two leagues would play a total of 72 exhibition games over the next three seasons, so a substantially larger sample size than the four championship games. But how much can we really take from preseason contests? For the modern fan, the initial reaction is probably nothing. However, I think we can take quite a bit from those games. You have to put the games into the context of their times. Exhibition games at the time were not the absolute afterthoughts they are today. From 1960-1966, the eventual NFL division champions combined to win 74.7% of their preseason contests, compared to 80.2% in the regular season. In the AFL over the same period, the division champions won 63.1% of the preseason games and 74.7% in the regular season. In both cases, we see that the eventual winners did tend to win in the exhibition contests as well. In fact, over the seven year period prior to the merger agreement, only 5 of the 28 division winners had a losing record in the preseason, while 7 of them had a perfect record (preseason schedules were typically 5 or 6 games then).

17 Comments | Posted in AFL versus NFL

AFL versus NFL: draft class peaks and declines

Posted by Jason Lisk on September 17, 2009

Before moving on to the draft classes of 1967-1969, I thought I would do another quick thought experiment, and while this post is included in the AFL versus NFL series, it certainly has broader application. Even if you are not interested in the specifics of the AFL versus NFL breakdown, you may find it informative as you assess how much the 2009 season will be determined by the 2007 draft class versus the 2002 class.

I've already looked at the draft classes of the early (1960-1963) and middle (1964-1966) of the decade. But how the heck am I going to combine all of that information to come up with a coherent overall view of how the two leagues compared? It's not going to do a lot of good to simply know how much talent the AFL got in 1960 versus 1964 if I cannot combine it in some meaningful way.

4 Comments | Posted in AFL versus NFL, Approximate Value, NFL Draft

AFL versus NFL: 1964-1966 Trends

Posted by Jason Lisk on September 2, 2009

For those that haven't been checking the blog on a regular basis through the off-season, this is part of a series on the AFL versus the NFL. For previous posts, we have now created a category and if you click here you can read all the others.

Let's now turn to trends developing in the middle part of the decade.

In the NFL, total offensive yards per game declined from the bubble of the early 1960's. Yards per attempt also decreased from the historic peak following rapid expansion, going from 7.9 in 1962, to 7.5 in 1963, to 7.2 in 1964, with a correction back to 7.5 in 1965 followed by a drop to 6.9 yards per attempt in 1966.

9 Comments | Posted in AFL versus NFL

AFL versus NFL: 1964-1966 Drafts

Posted by Jason Lisk on July 31, 2009

When it comes to the AFL, it may seem logical to think that the AFL was improving at a fairly constant rate, and that it would be doing better in terms of talent acquisition in year five, compared with year one.

After looking through the draft data and careers of the players, I would like to suggest an alternate history. The AFL came in and immediately made a splash against the NFL, signing several high draft picks and taking away a lot of young talent. I have the early drafts rated as wins for the AFL in 1960 and 1963, and for the NFL in 1961 and 1962. Overall, it was a great start for an upstart league.

In this post, I am altering my method for calculating draft value slightly.

10 Comments | Posted in AFL versus NFL, NFL Draft

AFL versus NFL: 1960-1963 Trends

Posted by Jason Lisk on June 1, 2009

Last time, I put the draft classes from 1960 to 1963 under the microscope to evaluate how both leagues did. Now, I'm going to go in depth on some of the age and experience trends from this period, and also look at positional and team trends. I'm going to have lots of data and charts in this post anyway, so to start with, I'll just link to the already existing pages at the website that summarize the yearly league numbers. The NFL season by season totals are here, and the AFL season by season totals are here.

We all know of the AFL's well-deserved reputation as a wide-open and wild passing league. The NFL in the early 1960's was changing its passing stripes as a result of the AFL expansion as well. In the late 1950's, the average completion percentage hovered around 50%. The completion percentage steadily climbed throughout this four year period. The expansion from 12 to 22 teams diluted the talent pool, and had an impact on defenses. A passer averaged 8.5 or more yards per attempt in a single season seventy-six times in the history of the NFL. Fifteen of those seasons (11 in the NFL, 4 in the AFL) came in this four year period-roughly 20%. Another 8 NFL passers reached the 8.0+ yards per attempt mark between 1960 and 1963, which means that over a third of all starting quarterbacks in the NFL in this time period averaged at least 8.0 yards per pass. The yards per attempt spiked at a league-wide average of 7.1 in 1962, a mark that hasn't come close to being touched since (2004 was the highest since the merger, at 6.6). Interception rates dropped during this time, and pass attempts climbed slightly from the 1950's. Overall scoring was up slightly (about 0.8 points per team per game), with a larger standard deviation, which makes sense given the poorer quality of some expansion type teams, along with the good offenses that were able to take advantage.

3 Comments | Posted in AFL versus NFL

AFL versus NFL: 1960-1963 Drafts

Posted by Jason Lisk on May 14, 2009

Last week, I posted my proposed methodology for evaluating the drafts of the 1960’s. A couple of quick notes before I get into the specific drafts. After considering Jim Glass' comment and reviewing the drafts, I’ve decided not to include the head to head wins and steals in my analysis. I’ll go into more detail in the 1961 draft section.

Also, there are players who signed with one league and then moved to another. Typically, this was a player who signed with an NFL team, sat the bench for a couple of years, then moved to the AFL after playing out their option. Ben Davidson and Ron McDole are examples of this. If we are looking at who did the best at signing players, we want to credit this player to the original league, but if we want to look at which league got the production, we want to credit the league where the player starred. I decided to not include these players in the draft value analysis at all. I did include them in my list of the best players for each league, if they otherwise qualified, for the league where they accumulated their value. Finally, the best players list for each year consist of (1) players drafted in that year, even if they debuted later, and (2) undrafted free agents who debuted that season. For 1960, (since there were so many “rookies” entering the AFL) I only included undrafted players age 23 or younger. For the best players, I decided to list at least 10 AFL guys and 15 NFL guys each year, but sometimes I list more.

9 Comments | Posted in AFL versus NFL, NFL Draft

AFL versus NFL: draft methodology

Posted by Jason Lisk on April 30, 2009

So far, the posts have not really gone into too much detail on the actual teams and players in the American Football League and National Football League during the 1960's. I've looked at how much we can really learn from four championship games, and also looked at expansion teams to get a sense for the rate of improvement we might expect from AFL teams over time, if they were getting equivalent talent to the NFL.

This should be the final stage-setting post before we get to actual details about the AFL and NFL teams from this period. At the outset of this project, I said that I didn't know exactly how many posts would come out of this project, or how it would proceed. And that was true. My plan moving forward as of today is to break the actual drafts up into three periods: early (1960-1963), middle (1964-1966), and late (1967-1969). I'll move chronologically forward, but will not go straight through with just draft discussion. After the early drafts, for example, I will discuss the league trends resulting from the start of the AFL, such as aging patterns, starter retention, and rookie starting rates for the two leagues. I think it will make more sense to do this immediately after discussing the specific players and drafts for the same period.

5 Comments | Posted in AFL versus NFL, NFL Draft

AFL versus NFL: expansion teams

Posted by Jason Lisk on April 12, 2009

Let’s start with a thought experiment, in considering how long it might take for a league like the American Football League to become equivalent to the National Football League. How long would it take for a team starting from nothing today to become equal with the rest of the league? If we assume that our new team has equal access to incoming talent, I think the very simplified answer is that it would roughly take as long as necessary for two things to occur:

1) For the incoming talent (where our new team is equal to the established teams) to mature and reach peak age; and
2) For the current star talent in the league at the time of our new team’s inception (which our new team is lacking) to decline and move past peak age.

How many years is this? My thought is roughly somewhere between four and six years. And that number is of course highly variable in an individual team scenario, depending on things such as how the original roster is created, the quality of the coaches and management, free agency, and primarily, luck and skill in acquiring young talent.

9 Comments | Posted in AFL versus NFL

AFL versus NFL: the Super Bowls

Posted by Jason Lisk on March 24, 2009

I'm going to start my discussion of the AFL and NFL by going where, for most people, the discussion begins and ends. The first four AFL versus NFL championship games (or Super Bowls as they came to be known) took on almost mythic significance. These 240 minutes of game action not only decided titles--they proved how good the two leagues were.

Once the American Football League established itself as having some staying power, the clamor for a championship game began. The December 16, 1963 issue of Sports Illustrated featured an article titled "The Two Pro Football Leagues Must Meet", which set forth an exchange between then AFL Commissioner Joe Foss and NFL Commissioner Pete Rozell. That issue also featured a point/counterpoint, with
Dan Jenkins setting forth the case for the AFL being competitive with the NFL,
and Tex Maule summarily dismissing the AFL with the retort, "Ridiculous! The NFL by 50 Points".

2 Comments | Posted in AFL versus NFL

AFL versus NFL: introduction

Posted by Jason Lisk on March 3, 2009

Next football season will mark the fiftieth since the American Football League began playing in 1960. With that historic anniversary approaching, I thought it would be interesting to take a look back and do an in-depth comparison of the teams in both leagues during the decade between the start of the AFL and the AFL-NFL merger for the 1970 season.

Ask someone who was around during this time how the AFL and NFL compared to each other, and you are likely to get a variety of answers, primarily dependent on where their allegiances lay. I hope to sort through this and provide a detailed statistical look that tries to bring all the available evidence to the table, put it in context, and try to develop a best estimate that answers both general and specific questions about the teams and leagues, and how they compared before 1970. This all may very well prove to be a fool’s errand, and but some of the types of questions which hopefully can be addressed include:

**When did the AFL catch up with the NFL during the 1960’s and become at least comparable competitors, if ever? Think of it in terms of kind versus degree. To draw a college football analogy, when did the AFL stop being the MAC to the NFL’s Big Ten—where a few teams may be able to be competitive but the rank and file would have trouble—and instead become the Pac-10, where one league or the other may have a better year at any given moment, but where we consider the talent roughly equal over time?

3 Comments | Posted in AFL versus NFL