Tarr's Blog

The genesis for this post comes from a post a long while back from the Atlantans, with a subsequent follow up by Parinella. It was also hit on by Degs on his/Hectors blog.  This got me thinking about the subject more generally - the length of the stall count, the field dimensions, and the effect of these rules on the game.

I like the rules of Ultimate in general, and I wouldn't want to drastically change anything. But it seems to me that by tweaking some of these more adjustable rules, you could get the "desired" dynamic in terms of scoring frequency. In order addressperly adress this, we need to know two things: how various changes will change the dynamics of the game, and what dynamics we really want.

The dynamic I would like can be defined very simply. I would like the offense to tend to score on about one half of its initial posessions, and the defense to score on roughly one half of the following posessions if they get a turnover.  I'm not too concerned about the third and subsequent posessions, but if we got the first two close to 50% each, I suspect that later ones would be around 50% as well.

I'll define the following five "variables" that we can change:

1) Field width
2) Endzone depth
3) Maximum stall count
4) Brick - the distance from the endzone line to the brick mark.
5) Brick-to-Goal - the distance from the brick mark to the goal for the offense.

The effects of these, as I see it, are as follows:

1) A wider field increases all chances of scoring.  It probably helps the initial offense more, in this case because they can use set plays and complex spread offenses more consistently.  Also, the most effective offense for a defense can be the fast break, which doesn't rely on a wide field to the same degree.

Aside from offensive/defensive slant, a wider field increases the effectiveness of spread offenses and reduces the effectiveness of zones and clams.

2) The deeper the endzone, the more likely either team is to score. It probably encourages more hucking, as you have more space to find the goal, and it reduces the efficacy of goal-line defense. The net effect of a deeper endzone is probably slanted slightly toward the initial offense as they are more likely to score on a big throw to space than the defense, but this is a marginal effect.

Deepening the endzone continues to have an impact all the way out to 40 yards at least, as extreme depth would mean teams would not need a separate endzone offense.

Aside from offensive/defensive slant, a deeper endzone encourages more long passing and places less of a premium on breakmarks and short cuts.

3) A higher stall count increases all chances of scoring. There is some point of diminishing returns at 20 or 25 seconds, at which point any team that cares at all aboupossessionning posession should be able to find a reset pass. The effect is about equal on initial offense and defense-turned-offense.

Aside from offensive/defensive slant, a higer stall count will probably discourage hucking and encourage teams to work underneath more, as they will have more confidence in their ability to find an easy look before they get stalled.

4) The longer the brick, the higher the chance of an initial offensive score. The effect on the defense scoring on its first chance is smaller, but a longer brick does hurt them, as it increases the average field position they need to cover to score. So longer bricks are a pretty easy way to help the offense, and vice versa.

5) Surprise time (for some): a longer distance from the brick to the goal does not dramatically hurt the offense's chances of scoring. It does hurt them, but only in the case of the brick. On all other pulls, however, the additional distance does not matter.

This conclusion is based on the assumption that very few teams have pullers who can consistently land a hanging pull in the back of the endzone. As such, the distance the offense has to go on non-brick pulls is determined not by the length of the field, but by the length of the pull.

On the other hand, the effect this has the defense's chance of scoring on its first posession is essentially the same as the effect that a longer brick distance has. A longer field means farther to go for the defense when they get the disc.

So, in total, a longer brick-to-goal distance does hurt both teams' chances of scoring. If pulling is extremely good or very brick-heavy, it hurts the offense more; for most normal pulling conditions, though, it hurts the defense more. There is a point (>70 yards or so) where any additional length is almost eniterely a negative for the defense and has no significant effect on the offense.

OK, with all that in mind, how do we tweak things?  Obviously, it depends on the level of play.  I'll provide a few examples:

Low-level play, few good hucks, short pulls, frequent turnovers: Wider field, deeper endzones, higher stall count, shorter brick-to-goal. Everything is slanted toward whoever is on offense scoring.

Low-level with lots of hucks, frequent turnovers:  Wider field, shorter endzones, higher stall count, shorter brick-to-goal.   This is a common dynamic in juniors ultimate, low-level open college, and some league play.  The goal is still to make it easy on the offense, but the shorter endzones discourages playing the field position game (otherwise the optimum strategy in these games) in favor of trying to work the disc more.

Mid-level, fairly skilled play, still plenty of turnovers: slightly higher stall count, longer brick. I'm thinking of a lower-level club game here.

Elite play, great pulling, good hucks, few defensive breaks: narrower field, shorter stall count, slightly longer brick-to-goal.

You could keep coming up with more permutations. The idea is that these things should match the level of play. I'd be comfortable with different divisions using different dimensions and different stall counts.

I think a decent working definition of a "50/50 ball" would be, "a throw that is too high to be caught towards the end of its flight, and takes long enough to descend to catchable height that at least one player from each team could easily reach the disc and catch it if there was no opponent contesting the catch." That's terribly wordy, but I think it's a decent working definition.

My point is just that a 50/50 throw is not truly 50/50, even if the players are equally good at reading and going up for the disc. Each side has a major advantage, at least in theory.

The defense has the advantage that if nobody catches it, they win. This means they can just swipe at the disc, which means that the defender effectively has a few more inches of reach. This also becomes a decisive advantage on a crappy throw or a throw that is wobbling in the wind, as nobody has a good look at catching those.

The offense has two advantages - one technical and one more subtle but much more important. The technical advantage is that if both players catch the disc at the same time, offense retains possession. The chance of this really happening is pretty close to zero, but it makes for a good argument in favor of keeping the disc when both players get a grip on it.

The other, much more significant advantage is that presumably the offensive player was at least somewhat open when the disc was thrown. Yes, this isn't always true, but it usually is. And even if all spatial separation is erased by the time the disc arrives, the offensive player still has the chance to get to the spot first. This means that, if you can read the disc, you can get the right spot. Having good position is far more important than the extra few inches being the defender gives you.

I know people aren't trying to say that a 50/50 throw is exactly 50/50, but it's useful to recognize the factors that go into it, other than the relative abilities of the intended receiver and the defender.

I played a winter league game yesterday. It was a rather galling experience because I felt the four best players on the field were all on my team, and yet we lost by two. It was especially galling because two other Purdue alums were on the other team, and I don't like giving those guys bragging rights. This game was a great example of a truism in league play - it's more important to have the better worst player than the better best player. In this case, we also had the three worst players, so there you go.

Anyway, at one point in the game, one of the league vets on my team was preaching short throws, patience, and the usual pablum. This was significantly directed at me, for (as I am wont to do in league play) I was letting it fly quite a bit. It seemed like an odd criticism to me, though, as I was actually having a pretty good day throwing long. I think the focus on me resulted from the combination of us having a lot of long turnovers, and me having a lot of long throws. At that point in the game I had had two long throwaways, and I had one more (in my defense, a terrible misread by the receiver) later on. But I also threw for five of the eight goals we had in the game.

Significantly, I had three short throw turnovers that I remember as well. (I probably had one or two other turnovers that I don't recall.) Even though I disagreed with my teammate's comment, his comment led me to think about how one's turnovers are distributed and what this says about your decision process. Let's assume for argument's sake that there is not a huge upwind-downwind effect which would motivate a field position game or drastically slant one's huck counts based on the offensive direction. Given that, and given that your team wants to employ a deep threat, what does the distribution of your turnovers say about your choices?

My instinct is that the proper choices in throws, as a team, would lead to a fairly even division between deep throw turnovers and short throw turnovers. That is, a histogram of team turnover frequency versus distance would be flat. High percentage throws are only higher percentage if they produce fewer turnovers.

This does NOT imply that you throw deep as often as you throw short, unless you are equally successful at both throws. Say you turn the disc over 10% of the time on short throws and 40% of the time on deep throws. (Yes, I know those numbers suck - if I was talking about club I would set the percentages lower.) In that case, assuming your deep throw percentage is not a lot lower than a teammate's, you should probably be throwing deep on about one fifth of your throws. This means you will turn the disc over 16% of the time you throw, with an 8%/8% split between short and deep.

Of course, your "true" percentage is unknowable, and you could end up throwing more or less deep throws depending on the situations you end up in. But I think this serves as a useful guide for both individual players who throw deep a lot, and team captains. As a hucker, take note if your huck turnovers exceed your other turnovers. There are exceptions to this (for example, Lucy's role on Purdue in 2005 was to huck it half the time she touched the disc, which was fine) but it is a red flag. And as a team, if your deep turnovers exceed your short turnovers, then unless field position demands that strategy, it's time to scale it back.