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Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog

The point of the post certainly wasn't to say "if you can score, playing defense is never worth it". That's the wrong lesson to take away here. At the end of the post the limitations of the specific scenario analyzed are touched on - not the least of which includes that you absolutely can't disregard alliance partners in a cost benefit analysis.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog

Quote:

Originally Posted by DampRobot (Post 1288351)

I do have to disagree with a few points in your analysis though, specifically regarding the "Team Plowie" match. I completely agree that often slowing down the top cycler on the other team just a little bit will cause them to drop a cycle and score significantly less. However, trying to do this yourself will often slow down your scoring much more than it slows down theirs. You touched on this, but it isn't effective defense because you're likely spending more time defending them then they are defended for. You usually have to wait around, then intercept them, and maybe even chase them for a little bit. That might make them drop a cycle, but it certainly will make you have less time to score.

You should probably go back and read the post. Specifically:

Quote:

We would like to point out that smart defense is very important…a bad defensive team will spend 10 seconds of driving to perhaps slow down the team they are defending by 2 seconds. A good defensive team could, and arguably should slow down an opponent by MORE time than the time spent defending.

So I have to assume you have not read or understood the article since you are disagreeing with a point and then going on to make the same point.

Quote:

I'd argue that instead, you should task one of your alliance partners with, if nothing else, just camping out behind the pyramid. That should make the other alliance's high cycling robot drop a cycle, and it won't impact your scoring at all (I'm assuming that this team would contribute <9 points anyway in teleop). If you're your team's primary scorer, you should focus on scoring. Other people can play defense and improve the difference in score much more.

I have to strongly disagree with this. I used a dynamic strategy during eliminations at Orlando and DC. All of our robots were approximately equally capable of scoring. This allowed us to harry opponents as we went back to reload, a little bump here, getting in the way there. But since all of us were removing maybe 1 second a cycle we were able to reduce their scoring far more than if we had assigned one of our robots to defending. I'd say it was pretty successful.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog

I agree with Andrew, we were finalist at Razorback and one of the keys to our strategy was that our driver knew if he had a shot at one of their robots in the middle of the field he took it. We weren't playing the full defense strategy we had at IRI since we were the best offensive robot on our alliance as well but a few well placed hits can swing a match. Especially if those hits can affect the other team more than they affect you, like knocking frisbees out of their hoppers, moving them to less optimal scoring positions, that sort of thing.

In many cases when you have a robot that won't give you much on offense it's okay to have them play D the entire time but when you're lucky enough to have 3 quality offensive machines *cough* World Champions *cough* this strategy works well.

Oh and thanks for bringing the blog back. I love this stuff.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog

Quote:

Originally Posted by DampRobot (Post 1288351)

You touched on this, but it isn't effective defense because you're likely spending more time defending them then they are defended for.

What about a pushing match where you push an opponent toward your loading zone? That gets you where you need to be, takes them away from where they need to be, and takes up an equal amount of time for both teams. That's causing the opponent to waste more time than the active defender put into defending.

What about if it takes 2 seconds of defense to force a tall robot to go the other way around the pyramid? This can result in about 5 seconds of delay just from being in the right place at the right time, and it could likely result from just spending an additional 1-2 seconds during a single cycle to be in their way enough for them to decide to go the other way.

What about a floor loader hassling a loading opposing cycler in their unprotected feeder station? It will make their loading slower/more difficult and result in some likelihood that they will drop some discs on the floor for you to collect...that would be a win-win because it slows down their cycle time and speeds up your own.

The point of the post is that opportunistic defense can narrow or widen a point margin between two robots or two alliances if used properly. A point prevented = a point scored, so the fact that the point margin in the example shown goes from 19 points to 10 points is tremendous. If one of your partners has a match where they get 1 more cycle than they usually do, the act of playing defense can help turn a close loss into a close win.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog

Time, like cycles/shots on goal, is a secondary metric. It's not actually points. Even if both teams spend the same amount of time on a non-scoring activity (such as a pushing match), they don't necessarily lose the same amount of points.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog

Has this blog been discontinued? I really liked it last year, but it just sort of disappeared.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog

I've been pretty busy at the job I get paid for, so haven't had much time to build a robot, let alone write about them. :o

Right now, it looks like my work schedule rebalances sometime after the Championship, so I don't think I will be contributing much. Andrew Schreiber was the other co-conspirator, I'm not sure what he's been up to. If anyone has some cool statistical stuff along the same lines, I'm glad to put it up. :)

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog

Quote:

Originally Posted by Ian Curtis (Post 1348692)

Yeah, so fun facts Ian and I both have this full time job thing. (I actually just moved 2 months ago up here to the frozen north)

So, basically TwentyFour (and, truth be told most of EWCPcast) is on hiatus for a little while. We enjoyed writing them for you guys and I think we'll do our best to bring it back in a little while. However, in the mean time - if you guys have any requests for topics for us to cover send 'em our way (this thread works or PM Ian and I) and we will see what we can do. OR if you really feel ambitious, write an article. We'll give it a quick once over, and post it up (crediting you of course).

I just put in for a slot at CMP to do a conference talk, it's a little more technical than last year, we're aiming to cover timing in FRC: how to make mechanisms operate in times and how to derive timing requirements based off strategy.

I wish I had time to do more of this right now but unless someone can figure out how to add about 6 more hours to each day I can't.

Sorry :(