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Comment by notahacker | Hacker News Reader

The flip side of this is that some of the best elite penalty takers essentially outthink the opposing goalkeeper. The safest penalty is placed slightly to the opposite side to the one the keeper dives to, which has plenty of margin for error (and if the keeper doesn't move early they're not saving anything that isn't down the middle)

Smashing a ball into the top corner [without needing to think about it] is also unsaveable and popular with elite penalty takers, but the margin for error in how you actually kick the ball is smaller: a slight miscue and your penalty is off target (or a "nice height" for a keeper that reads where you're shooting).

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> Smashing a ball into the top corner [without needing to think about it] is also unsaveable and popular with elite penalty takers, but the margin for error in how you actually kick the ball is smaller: a slight miscue and your penalty is off target (or a "nice height" for a keeper that reads where you're shooting).

I like the fact, that penalties on the sides of the goal above a height of about 1,5m are unsaveable (you do not even have to hit the corner), but still world-class players miss, because they get nervous, so they often do not dare to just do that. It should be a game like tic tac toe: Totally solved, the keeper should lose every round, but yet he does not. Makes the game human.

> and if the keeper doesn't move early they're not saving anything that isn't down the middle

Most penalties are poorly taken. I hate seeing a keeper dive early to a random side only to be beaten by a weak shot down the middle. I assume that keepers don't have faith in their nerves/reactions and thus have to force their bodies to dive before the shot is taken. Otherwise the best strategy for the keeper is to wait for the shot

Have you considered that the few people who have managed to rise to the top of one of the most competitive fields in the world, as well as the clubs who have have many millions of pounds depending on the result of a penalty kick ... may possibly be better at taking penalty kicks, and are more aware of the best strategy than yourself?

The underhand free throw is a counterpoint to your appeal to authority:

https://www.nytimes.com/2017/02/08/sports/ncaabasketball/und...

That seems like it would be an irrelevant conclusion if we were to be playing hacker news bingo.

Welcome to HN. You see these kind of posts on every topic (I have had first-hand knowledge of a certain event, and you come on here and someone will tell you with authority that you are wrong...and actually X/Y/Z happened...this place is very unique).

What people also underestimate is how hard professionals hit the ball, without looking like they are hitting it hard. I had a relatively hard shot, I have injured GKs in pens, I trained with a guy who was once a reserve keeper for a lower division professional side (retired a few years)...I didn't come close to scoring because my shots were nowhere near hard enough. Free kicks are the same, you see the shot in slow-mo, it looks like they are swatting the ball softly...in reality, their technique is so good/efficient that they are crushing it whilst aiming it carefully.

Most professional clubs employ people who just look at penalties. They look at techniques, they look at strategies...saying that the keeper should wait for the ball when it is going 70mph and you have under 100ms to decide is...ludicrous.

You and the parent you are replying to are right - pro clubs know the ins and outs of penalties and select and train players (keepers and takers) accordingly.

You are being distracted from the meat and bones of the argument though - the whole premise that most penalties are poorly taken is blatantly wrong. Most penalties end up in goals - which is how it's intended to be.

If the goals were smaller and most penalties did not result in goal that would not mean they are poorly taken.

These people are obviously the best in the world at what they do, they are picked specifically and paid generously in order to be able to kick a ball into a net. Discussing casually how they could improve without any apparent indepth knowledge is a level of hubris that hackers news is known for breeding.

> If the goals were smaller and most penalties did not result in goal

Then they arguably wouldn't be penalties.

But there's no need to argue with me, I've been watching football for some odd 30 years and playing for a good subset of that. It has never occurred to me that penalties are taken poorly at the pro level - I've seen absolute dross at the amateur level, but I concur that most pro penalty takers are phenomenal, both from a statistical and aesthetical perspective. Not that I think there is that much value in the latter - by design, a penalty kick is the most aesthetically boring of all set pieces. A penalty kick ensues higher emotions due to the odds at play, but from a purely aesthetical point of view, I'd argue that even a corner kick has a much higher potential (a volley, a bicycle kick, a header, a fine-tuned "chess play" that cracks the defense open, etc.)

And a penalty kick doesn't compare to the myriad other open plays in football which have infinitely more aesthetic appeal. A penalty kick is about creating a certain balance of odds, simple as. Every other consideration is secondary.

By poorly taken, I mean aesthetics not effectiveness. See here:

https://news.ycombinator.com/item?id=27256085

Yes, goal frequency is 75-85% in professional play. Amazing but it shows how much skill takers have (players like Baines, Henry, and more recently Fernandes are over 90%...which is just crazy).

C'mon, I literally said the same conclusion that keeper's reactions aren't good enough.

> I assume that keepers don't have faith in their nerves/reactions and thus have to force their bodies to dive before the shot is taken.

Yes, and I am saying no-one has reactions that fast. Professionals hit the ball 70-80mph...up the chain someone said that keepers should just wait and see where it is going: this isn't humanly possible, there isn't enough time.

What they do is: statistical analysis of every penalty taker to see what preference they have (what corner, what they do home/away, what they do when they are facing a goal at a certain end, etc.) and most professional goalkeepers are pretty much experts in watching how players run up to the ball, how the taker's eyes move, how they position their body, how they position their non-striking leg (and strikers counter this: you will notice that most professional takers will look at the ball when they put it down, turn away from the keeper when they walk back, usually keep looking at the ball or directly at the keeper before they start running, and not look away from the ball when running up...there are reasons for this). And clubs will analyse videos of taker tendencies, and keeper tendencies.

We're talking at cross purposes. See here:

https://news.ycombinator.com/item?id=27256085

Also fwiw just because > Most professional clubs employ people who just look at penalties. They look at techniques, they look at strategies < doesn't always result in professionals choosing the best technique or strategy. Here's an example:

https://www.nytimes.com/2017/02/08/sports/ncaabasketball/und...

Yeah, wait for the shot and always late for a save. They do this for a living, they move before ball rolling for a reason: human not fast enough for a shot from pro.

Not fast enough for a shot from a pro, a good shot to the top right corner sure. But a penalty shot straight down the middle? A keeper isn't fast enough to catch that?

Most kickers aren't going to do a penalty shot straight down the middle if the keeper is just standing still in the middle.

which is what I want:

> I hate seeing a keeper dive early to a random side only to be beaten by a weak shot down the middle

So you want a keeper to just stand in the middle and never save anything while everyone shoots to the side?

Penalty takers aren't perfect and the keeper will save a few

The keeper won't save as many. You're arguing that the keeper should carry out a suboptimal (non-Nash equilibrium) strategy just to satisfy your aesthetic preferences?

If you look at the numbers, a decently hard shot has the ball travel faster than 20 m/s, so the ball is at the goal line 0.5 seconds after the shot. Now, that means the goalie has to travel at something like 7 m/s. For comparison, the long jump world record traveled at 10 m/s, but not from a running start. [0] So allowing for reaction time and some delay because the ball need to travel a bit distance before one can see which direction it travels, it is simply not possible to react to a well shot penalty.

However, that is numbers for professional sports. In amateur, the ball will be shot at a somewhat lower velocity, and importantly, amateurs are a lot less likely to actually shoot a well placed penalty. So in lower leagues, it is a more reasonable strategy to try to react to the ball.

[0] https://www.wired.com/2012/08/long-jump-air-density/

> Most penalties are poorly taken.

According to a study of over 100,000 penalties by InStat, about 75% end up in goal [1]

It's easy to argue therefore that they fulfill their objective within the rules of football: to concede significantly positive scoring odds to an opponent who has otherwise been denied the opportunity to do so.

From what perspective are most penalties poorly taken? Classical mechanics, aesthetics...?

[1] https://instatsport.com/football/article/penalty_research

Aesthetics wise. It's a 'penalty' shot, it'd be pretty ineffective penalty i.e. punishment if the shot wasn't often successful.

So I'm unhappy with the Aesthetics because keepers know it's largely successful and just guess and jump the gun (or study the stats of the takers and then... just guess) which in turn let's the the takers focus on faking out the keeper with stutter steps and weird run ups. I prefer to see penalties where the kicker focuses on the skill of putting it in a spot nd the keeper responds to that.

They instituted (or started enforcing) the rule that keepers can't jump off the line before the kick is taken. For purely aesthetic reasons, I'd like something similar so they react to the ball instead of guessing

The rule revision you're alluding to is merely focused on the statistical outcomes and advantage distributions, and not aesthetics.

> I prefer to see penalties where the kicker focuses on the skill of putting it in a spot nd the keeper responds to that

It's fine that you prefer this, but this isn't what the penalty rule is about. The rule is balanced so that you create a sufficient advantage for the taker. If you pile requirements on the taker, you probably need to compensate with other advantages (ex: take the penalty from 10m instead of 11m). I can see why this is not something that FIFA would want to touch, ever.

> If you pile requirements on the taker,

The requirement is actually for the keeper not the tacker. But yes, I know I'm tilting at windmills

Most weak shots down the middle (by competent penalty takers that aren't a bag of nerves) are a conscious reaction to the keeper moving to the side the player hoped to slot his penalty.

If the keeper doesn't move, the ball is comfortably stroked/smashed past him on that side.

I have often thought about this, especially in penalty shoot outs where there are 4 people who aren't the "best" penalty taker that have to take one.

As has been mentioned there are penalties that are just unsaveable and against an elite penalty taker maybe a goalie is better off just picking a side and taking a chance against them but against the rest of the takers I'd be thinking eliminate the chance they get a freebie by diving too early or just picking a side and force them to score the hardest penalty possible

Riffing off your thought:

Perhaps goalies should treat penalties like free kicks i.e. the goalie doesn't stand at the center of the goal and offers a far corner for the kicker to aim at? The goalie knows exactly where the kicker should be placing the ball and if the kicker is perfect accurate it's a goal but if the kicker is off then the goalie should save it?

The average penalty kick crosses the line in about 700 milliseconds.

Doesn't sound humanly possible to assess the flight of the ball, prepare your footing, and then finally dive up to 3.5 meters to get to the ball.

In fact, don't "down the middle" kicks succeed more often?

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