Interesting observation on stats for this year (to the end of March)

I was looking over the year aggregate stats for defense damaging this year and I noticed something interesting:

The percent of successful damages to class C defenses goes down in playoffs, by about 0.58%.

It’s nearly negligible, but I still found it interesting.

3772/12656       29.8%

776/2656         29.22%

I find it interesting that there has been exactly 10000 more qualification matches than elimination matches. What a coincidence

Probably because nobody has a very fast Class C breach. I saw a few robots try in quals at North Bay, but they’re typically slow and finicky, and the floppiness of the drawbridge makes it harder. The most reliable way to go through the drawbridge and sally port is to have it opened for you from behind.

I think in elims people realize that the time spent for two or three robots to coordinate a Class C defense crossing, is better spent having those robots line up an extra few goals instead. There are generally enough low bar robots that the breach can always be obtained even while ignoring the Class C defenses.

I think you mean 10000.

Also, the total number of opportunities vary between defense classes. Probably just some data glitch. But it still is about a 10000 match difference.

A - 12663
B - 12665 
C - 12656
D - 12655

A - 2660
B - 2656
C - 2656
D - 2652

Sometimes the FIRST API returns “unknown” for a defense. I believe this happens because recording what a defense is isn’t required for a match to begin.

Right now a z test of the data yields a p-value of .273 (i.e. very not statistically significant). That means there is a 27.3% chance that this is just random chance causing the gap, not an actual correlation. Until we get more data or the gap grows substantially, we can’t conclude that there is any correlation rather than just random chance. Statistics ftw.

There’s more boulder shooting in the playoffs, and less focus on scoring through defense crossings. Class C slows down shooting teams too much.

What “gap” are you referring to, and to whom are you responding?

There’s no quoted context for your post, and it’s linked to post #5

I agree with this assessment. The class C defenses typically take a lot of time relative to the amount of point that can be attained. If a bot can’t do it solo, it is not efficient to have two bots tied up to get 5 points.

I believe the importance of class C in Elims was discussed on Gamesense this last week. What I came away with was the opinion that as alliances increase in skill and start capturing and breaching every match, regardless of defense, those 10 points will be more and more critical for securing the win. So I would expect those stats to start shifting in the opposite direction as we go forward. I wouldn’t expect that championship level alliances leave those points on the field.

I do agree that doing it solo is the best way to do it, I think that teams like 118 and 1197 that can do those defenses quickly (or in auto!) will be more valuable picks than comparable teams shooting wise.

I think one contributing factor is that in quals you more often have to deal with a random robot getting stuck or dying on a defense, which forces the alliance to attempt the class C defense. By eliminations, failure prone robots have been filtered out and teams don’t bother with class C due to time/difficulty/specialization.

I was referring to the gap between the percentages of C class crossings in quals vs elims. There just isn’t a big enough difference in the percentages given the sample size to be statistically significant, even if there are many perfectly valid reasons why there may be less C class crossings in elims.

I was responding to the OP (or just trying to provide added insight in general). If my post was linked to post#5, it wasn’t intentional.

To respond to the OP (and link to it), go to the OP post and click the “Quote” button. That will link your post to the OP, and provide quoted context.

If you just click “Post reply” it will reply (and link to) to the most recent post, not the OP. With the wrong linking, and no quoted context, sometimes it’s not clear what your post is referring to.

Random guess, but it could also be that Drawbridge seems to me to be more common in Elims than Quals, which could be contributing.

No stats to back this up at all, obv.

Here are the stats.

Drawbridge frequency in quals: 30.3%
Drawbridge frequency in playoffs: 27.2%


Oppa, I stand corrected. thank you for the numbers.

I guess I’ll renege to the more plausible explanation, then, that this isn’t statistically significant at all.

It’s quite concerning that the Sally Port and Drawbridge (Class C Defenses) don’t actually have a higher frequency in eliminations.

Class C defenses have typically been tackled by two robots working together, one propping the door or bridge open, the other driving through. Some alliances have made it as part of their game play, having their best two robots go through together, others have put poor robots to the task as a “side job” so that they don’t interfere with the “carry” robot, that can do all defenses except Class C. This almost guarantees that they won’t have to worry about a robot getting on a defense that they can breach. If the two robots manage to get it, no complaints, extra points - it’s a win-win.

A reason to not see the Class C with a higher frequency in eliminations is just that - there isn’t more than one poor robot that need to be given a “side job”.

However, the Class C defenses could play a very important role as the quality of FRC Stronghold matches improve. It’s quite plausible that we will still see 2nd pick robots that struggle to do much, even in regards to crossing terrain defenses. It is safe to assume though, that they will be able to drive on a flat surface. This is where the Class C defenses can tie in to add a 10 point bonus to an alliance’s “end game” (the last 20 seconds of their match). The offensive robot can come from the other side, and prop the door open for the 1st pick. The 2nd pick, assuming limited terrain crossing, but still capable of driving, can cross the C defenses as they are just a bump once the door is open. All three robots can then drive across into the courtyard, train formation (choo, choo!), positioning all three robots in a very capable position to challenge the castle. As we reach Championships, this triple challenge will become important, as we’ll be seeing many more towers being reduced to 0 strength.

An important thing to note is that this play could be carried out in Qualifications or Eliminations. However, the plausibility of it being carried out successfully is much higher in eliminations (which leads me to believe that the frequency of C defenses being crossed in Eliminations will eventually beat the frequency of C defenses being crossed in Qualifications). This is due to the fact that you are playing several consecutive matches in Eliminations with the exact same alliance. This allows you to fine tune your execution of such a strategy, smoothing out your game play, and making way for a more coordination-involved play like the one listed above.

The other benefit of putting your so called “poor” robots on opening the sally port / drawbridge is that it allows the “good” robots several seconds to actually see the courtyard, collect stray balls, etc. This combined with the effective point contribution being equal to two extra high goals, makes it something very much worth using your two worst robots on if they have time to do it. Not hard to have your #2 scorer hold the door open as your defender returns to your side of the field, then you quickly loop back to get the double cross before landing on the batter.