odds of getting hit by a ball?

[BQst]

Hi everyone,

 

First, a quick note to the mods. Can't figure out where to put this post. This section is described as "General golf related topics" so here goes...

 

My wife and I are house shopping, and we have found a great house in a private golf development, right next to the 7th green. It's roughly pin high and has a great view of the green and back up the fairway to the tee box.

 

The rub is we a 2 year old, and have no idea how big a risk the location will present. Does anyone have a sense of the odds he'll get hit by a golf ball?

 

The driveway is about 35 yards left of the center of the green, and the back yard is about 50 yards left. The hole is a heavily bunkered, short par four, measuring only about 300 yards from the white tees. The choices for play include two 150 yard shots, one 200-225 yarder plus a pitch in, or bombing it the whole way in one shot. As is probably obvious, that last option that scares us the most, as it's quite common to hit a driver well off line.

 

We understand life is full of risks, and we're not about to have our son wrapped in bubble wrap to protect him from all possible sources of harm. We don't care if the house gets hit by the occasional golf ball, and even a broken window or two over a lifetime of living there is fine. But what level of injury risk are we talking about?

 

Are we basically guaranteeing an unhappy visit to the emergency room? Or could we probably live there 100 lifetimes without that happening? We have no clue and would appreciate any insight you may have.

 

Thanks to everyone in advance.

 

-Ben

[usfbulls09]

Figure that your house will, in all likelihood, be hit a few times. That's the cost of living on a golf course. As far as your son getting injured, this is far less likely. Generally, people are more controlled with their 150 yd and in shots, and 50 yards off the target is quite the miss, you have to figure that's not going to be the norm. Now, as far as drives hitting your house, I'm pretty sure you're safe there. A drive would have to be 300+ straight on line to get to your house, if it's as you described. A hooked shot is not going to travel 300 yds in the air to your house, I'd be more worried if you were along the middle of the fairway, then I would say you'd be in some trouble. The approach shots are less likely to be that off target, so I'd say you're going to be okay there. My cousin's house is in almost the exact same position in his community, and while a few balls make their way into the backyard, it's not too bad really, and his house hasn't even been hit (yet). Your 2-yr old won't be wandering on to the course or anything, so I don't think he's going to be in danger. I can understand your concern, but know that thousands of people live on golf courses without incident, so more than likely you'll be good to go.

[rufus mangler]

There's a bunch of reasons NOT to buy on a golf course. Price, noise, lack of privacy, damage by guys who think it's YOUR fault, chemicals, mowers, etc.

Everyone with half an ego is going to come out of their socks to hit this green, (or try to). My miss goes left. Are you going to hear guys screaming F***! every time you BBQ, or see somebody talking to your son as he scans the yard for his (once hit) Pro V? Personally, I wouldn't want any "odds" of my son being hit by anything.

Sorry to be the heavy, but it would have to be one nice house.

[jewofgolf]

Since my job is to determine odds, I will go ahead and give this one a shot.

First of all, I agree with Rufus that golf courses may not be the most desirable place to live. I think you should definitely be aware of all the things going on at a golf course operation. Mowers waking you up at 5 am on the weekend would be an example.

Now to the fun part! Please assume these statistics to be best guesses and only a proxy for the true probability. I will add an error factor in at the end.

Approximately .1% of golfers ACTUALLY could drive the ball far enough to hit your house. I'm a +1, and I know I can't hit your house unless the hole is playing way downwind and a absolutely kill it to carry it the 310(house is left, use Pythagorean theorum to approximate this).

Of that .1%, I would guess that only 10% are going to play the white tees. Most good players are playing the tips.

Of that .0001, Half will play a fade.

Of that .00005 who draw the ball and can hit your house, let's say 1/4 of the time that they are taking a big rip, they hook it.

Of that .0000125, let's guess that 1/2 of the time they hook it left, they hook it the correct amount to hit the house.

Thus, the probability of a tee shot hitting your house is .00000625.

There is a small chance somebody hits an approach shot into your home. I'm going to hand wave and call this .0000001, since I think it is extremely close to 0, anyway. Bad players slice the ball....most who would miss a green by 35 yards from 120-150 are really bad players, but...it is possible they will get to your house.

The probability for a single shot hitting your house is .00000635. This equates to 1 in 157,000 or so shots.

Let's assume that 100 groups play per day, on average, this hole. This includes winter and rainy days. Make that 400 people daily then.

Let's look at a 10 year time horizon as the relevant time period for your son's endangerment.

This equates to 1,460,000 golfers on the hole in that time span.

Here is a chart listing the binomial probabilities for your home to be struck:

Probability Times Hit
0.000094112 0
0.000966626 1
0.005011187 2
0.017510293 3
0.04648022 4
0.100196453 5
0.183197229 6
0.293126073 7
0.420520061 8
0.551750138 9
0.673413565 10
0.775953662 11
0.855174338 12
0.911670762 13
0.949083405 14
0.972206838 15
0.98560537 16
0.992912265 17
0.996675702 18
0.99851205 19
0.999363284 20
0.99973908 21
0.999897443 22
0.999961277 23
0.999985935 24
0.999995079 25
0.999998339 26
0.999999459 27
0.99999983 28
0.999999948 29
0.999999985 30
0.999999996 31
0.999999999 32

Notice that it is very likely to be hit. These are cumulative values, so don't yell at me for not using point masses. I thought this would illustrate the point better.

Anyway, let's use the 32 number, assuming this is a reasonable number of times that the house will be hit. I'm now going to add in an error measure, another hand waving, and call this number 50.

Let's assume Your backyard and the entire house have different probabilities of your son's presence at any given point in time during the day. If the house is 2000 square feet, and the backyard is 10,000, let's just make a rough guess that the adjusted square footage for this calculation is about 3000 square feet.

Your son occupies about 2 square feet on the ground.

Given that about 50 balls will hit your home in the next 10 years, and that is has to hit a probability area of 2/3000, let's put the expected number of balls hitting your son in the next 10 years at 1/300, or .003333.

Basically, don't worry too much about it, but I would add into your homeowner's policy a no deductible window replacement program, as long as the premium you pay for it isn't too much more than the expected cost of 1 window per year. I estimate you will have 6 to 7 broken windows in the next 10 years.

I hope you've enjoyed this analysis.

Marcus

[Sawgrass]

Are there any marks on the house that look like they were made by golf balls?

 

Have you asked the current owners about their experience (you never know, you might get a straight answer -- even one like, "It hardly ever happens, maybe once a month . ." could give you some more to think about.

 

Adults knowingly taking the risk of injury for the reward of getting the house they want is one thing, but taking that risk on behalf of a child is quite another. You are already concerned about that ethical issue, so I suggest that you may just feel bad about the decision to buy if you go ahead with it even if nothing ever goes wrong. Stated another way, just what odds would be acceptable to you? Try to put some numbers to that. If someone told you, "one in a million", would that be a risk you would take? One in a hundred thousand? One in a thousand? This estimatiing is a creepy exercize that may give you the answer you seek.

 

Edit: Or, you could just read the post prior to mine, which wasn't up yet at the time I wrote this . . .

[jirizarry]

Since my job is to determine odds, I will go ahead and give this one a shot.

 

First of all, I agree with Rufus that golf courses may not be the most desirable place to live. I think you should definitely be aware of all the things going on at a golf course operation. Mowers waking you up at 5 am on the weekend would be an example.

 

Now to the fun part! Please assume these statistics to be best guesses and only a proxy for the true probability. I will add an error factor in at the end.

 

Approximately .1% of golfers ACTUALLY could drive the ball far enough to hit your house. I'm a +1, and I know I can't hit your house unless the hole is playing way downwind and a absolutely kill it to carry it the 310(house is left, use Pythagorean theorum to approximate this).

 

Of that .1%, I would guess that only 10% are going to play the white tees. Most good players are playing the tips.

 

Of that .0001, Half will play a fade.

 

Of that .00005 who draw the ball and can hit your house, let's say 1/4 of the time that they are taking a big rip, they hook it.

 

Of that .0000125, let's guess that 1/2 of the time they hook it left, they hook it the correct amount to hit the house.

 

Thus, the probability of a tee shot hitting your house is .00000625.

 

There is a small chance somebody hits an approach shot into your home. I'm going to hand wave and call this .0000001, since I think it is extremely close to 0, anyway. Bad players slice the ball....most who would miss a green by 35 yards from 120-150 are really bad players, but...it is possible they will get to your house.

 

The probability for a single shot hitting your house is .00000635. This equates to 1 in 157,000 or so shots.

 

Let's assume that 100 groups play per day, on average, this hole. This includes winter and rainy days. Make that 400 people daily then.

 

Let's look at a 10 year time horizon as the relevant time period for your son's endangerment.

 

This equates to 1,460,000 golfers on the hole in that time span.

 

Here is a chart listing the binomial probabilities for your home to be struck:

 

Probability Times Hit

0.000094112 0

0.000966626 1

0.005011187 2

0.017510293 3

0.04648022 4

0.100196453 5

0.183197229 6

0.293126073 7

0.420520061 8

0.551750138 9

0.673413565 10

0.775953662 11

0.855174338 12

0.911670762 13

0.949083405 14

0.972206838 15

0.98560537 16

0.992912265 17

0.996675702 18

0.99851205 19

0.999363284 20

0.99973908 21

0.999897443 22

0.999961277 23

0.999985935 24

0.999995079 25

0.999998339 26

0.999999459 27

0.99999983 28

0.999999948 29

0.999999985 30

0.999999996 31

0.999999999 32

 

Notice that it is very likely to be hit. These are cumulative values, so don't yell at me for not using point masses. I thought this would illustrate the point better.

 

Anyway, let's use the 32 number, assuming this is a reasonable number of times that the house will be hit. I'm now going to add in an error measure, another hand waving, and call this number 50.

 

Let's assume Your backyard and the entire house have different probabilities of your son's presence at any given point in time during the day. If the house is 2000 square feet, and the backyard is 10,000, let's just make a rough guess that the adjusted square footage for this calculation is about 3000 square feet.

 

Your son occupies about 2 square feet on the ground.

 

Given that about 50 balls will hit your home in the next 10 years, and that is has to hit a probability area of 2/3000, let's put the expected number of balls hitting your son in the next 10 years at 1/300, or .003333.

 

Basically, don't worry too much about it, but I would add into your homeowner's policy a no deductible window replacement program, as long as the premium you pay for it isn't too much more than the expected cost of 1 window per year. I estimate you will have 6 to 7 broken windows in the next 10 years.

 

I hope you've enjoyed this analysis.

 

Marcus

 

 

 

Dude... I'm IMPRESSED!!!!!

 

 

[CowtownTexas]

Too many scientific answers here.

When I was a kid, my grandparents lived on a golf course. It was a private course that didn't get a massive amount of play. Their house was about 40 yards behind a tee box. The nearest green was about 80 yards away (the edge of a large green).

Their backyard caught plenty of golf balls in a spot where you think you'd see very few.

I have a three year old and I wouldn't take the chance of her playing in a backyard such as you've described.

[thekidjjv]

Not sure but its happened twice. One time was 8" above the franks and beans, and it felt like I got shot.

[j-rob]

Maybe you should invest in some netting

[Sawgrass]

[quote name='jewofgolf' date='21 March 2010 - 09:48 AM' timestamp='1269179325' post='2330738']
. . . Please assume these statistics to be best guesses and only a proxy for the true probability. I will add an error factor in at the end.


Anyway, let's use the 32 number, assuming this is a reasonable number of times that the house will be hit. I'm now going to add in an error measure, another hand waving, and call this number 50.

Let's assume Your backyard and the entire house have different probabilities of your son's presence at any given point in time during the day. If the house is 2000 square feet, and the backyard is 10,000, let's just make a rough guess that the adjusted square footage for this calculation is about 3000 square feet.

Your son occupies about 2 square feet on the ground.

Given that about 50 balls will hit your home in the next 10 years, and that is has to hit a probability area of 2/3000, let's put the expected number of balls hitting your son in the next 10 years at 1/300, or .003333.

[/quote]

Hi Marcus,

I'm also impressed. You clearly know way more than I do about this statistical perspective, but let me ask you a question or two.

One of the assumptions you made was that the boy occupies 2 square feet on the ground. I think it's fair to presume that a shot hitting the yard will be coming in at a decending angle, and as the boy grows he will be taking up more and more cubic feet even if his square-foot "footprint" remains about the same. As the danger isn't simply being hit on the foot (near the ground), do you agree that the odds of him getting hit anywhere on his body should be increased, or did your calculation take cubic feet into consideration in some way that I didn't detect?

Also, does your calculation presume that the boy was always outside during golfing hours? If it does, and if he only spends 10% of his time outside in the yard, am I correct that assumption decreases his odds of being hit down to one in 3000?

(As I ponder all of this, I reaffirm my earlier assertion that it's creepy!)

[2bGood]

[quote name='rufus mangler' date='21 March 2010 - 05:04 AM' timestamp='1269173060' post='2330642']
There's a bunch of reasons NOT to buy on a golf course. Price, noise, lack of privacy, damage by guys who think it's YOUR fault, chemicals, mowers, etc.

Everyone with half an ego is going to come out of their socks to hit this green, (or try to). My miss goes left. Are you going to hear guys screaming F***! every time you BBQ, or see somebody talking to your son as he scans the yard for his (once hit) Pro V? Personally, I wouldn't want any "odds" of my son being hit by anything.

Sorry to be the heavy, but it would have to be one nice house.
[/quote]


I am with you, I love golfing, but doubt I would want to live on a golf course. I have two kids under 6 and I would not want them running around the back yard described here. (funny that I will take my 5 year old out to the club all the time with no worrie though)

[offapex]

with a 2 yo I would never buy a house adjacent to a golf course. the odds might be 0.00001% of getting hit, but the consequences are too severe. imagine your child never being able to see again (getting hit in the eye).

[skizix]

Maybe you should invest in some netting

 

 

with a 2 yo I would never buy a house adjacent to a golf course. the odds might be 0.00001% of getting hit, but the consequences are too severe. imagine your child never being able to see again (getting hit in the eye).

 

These are the two most relevant answers, IMO.

 

Agreed it is a slim chance the kid would get hit. But the potential consequences are too grave to risk it, I think. And it's not just like you'd have to worry about 'em getting hit when you are not directly supervising. If a ball were screaming in for impact, there's not much you could do even if you were pretty close by -- if you even saw it coming. Seems unreasonable to assume you'll monitor every player hitting a shot potentially in your direction. I'm no safety freak, by any means, but a golf ball at speed could do some pretty bad things, even kill (e.g. if it were the classic temple strike).

 

Sure, no one wants to look at huge netting, but it doesn't exactly look out of place on a golf course (a few places on my home course have it -- non-subtle, but really, it looks fine). And if you choose, you could do it only through the toddler years or whatever. Think of it somthing like an enourmous baby gate, like you'd put on the stairs (um, only thing is: gotta be a hellava lot more expensive than any baby gate).

 

Perhaps, just maybe, your homowner's insurance would even drop the premium if you erect a decent net, which might offset the expense somewhat (I'm assume homeowner's is more expensive if you're right on the course, though I have no idea really).

 

For what it's worth: of the many houses that border my home course, only a very few look like they've got small kids -- to the point that I thought it was some kind of retirees-only/no-kids covenant neighborhood. But looking more closely, there are a few houses scattered in the bunch that have kids toys lying around the back yard. Very many fewer than in the surrounding area though, which has an uncanny number of young parents with young kids.

 

Anyhow, you just have to take a careful look at the particulare site and how vulnerable it looks. Best thing to do would be to play the course yourself (or at least walk that hole from tee to green) if possible, if you haven't already.

[BQst]

Hi everyone,

We can't thank you enough for all the helpful replies! The statistics in particular are a tour de force, and we also appreciate the added input with respect to noise, chemicals, 5am mowers, etc.

We haven't seen any marks on the house suggesting an impact, but the house has a lot of roof area which might not show anything from a golf ball strike.

Overall, we're in agreement with the majority that a different house is the best choice, at least until the little guy gets older. To frame things in golf terms, the odds of him getting hit by a ball seem considerably higher than the odds of me hitting a hole in one, and as bad a golfer as I am, we're not feeling comfortable with that.

Thanks again for all the help. I'd invite everyone over for a round at the course, which is very highly rated, but it seems like we're not going to be joining it!

-Ben

[jewofgolf]

[quote name='Sawgrass' date='21 March 2010 - 11:40 AM' timestamp='1269189624' post='2330997']
[quote name='jewofgolf' date='21 March 2010 - 09:48 AM' timestamp='1269179325' post='2330738']
. . . Please assume these statistics to be best guesses and only a proxy for the true probability. I will add an error factor in at the end.


Anyway, let's use the 32 number, assuming this is a reasonable number of times that the house will be hit. I'm now going to add in an error measure, another hand waving, and call this number 50.

Let's assume Your backyard and the entire house have different probabilities of your son's presence at any given point in time during the day. If the house is 2000 square feet, and the backyard is 10,000, let's just make a rough guess that the adjusted square footage for this calculation is about 3000 square feet.

Your son occupies about 2 square feet on the ground.

Given that about 50 balls will hit your home in the next 10 years, and that is has to hit a probability area of 2/3000, let's put the expected number of balls hitting your son in the next 10 years at 1/300, or .003333.

[/quote]

Hi Marcus,

I'm also impressed. You clearly know way more than I do about this statistical perspective, but let me ask you a question or two.

One of the assumptions you made was that the boy occupies 2 square feet on the ground. I think it's fair to presume that a shot hitting the yard will be coming in at a decending angle, and as the boy grows he will be taking up more and more cubic feet even if his square-foot "footprint" remains about the same. As the danger isn't simply being hit on the foot (near the ground), do you agree that the odds of him getting hit anywhere on his body should be increased, or did your calculation take cubic feet into consideration in some way that I didn't detect?

Also, does your calculation presume that the boy was always outside during golfing hours? If it does, and if he only spends 10% of his time outside in the yard, am I correct that assumption decreases his odds of being hit down to one in 3000?

(As I ponder all of this, I reaffirm my earlier assertion that it's creepy!)
[/quote]

Totally just a guess on the time spent outside and square footage and all of that. I just made a guess to add 1000 for the calculation. I don't have any "real" statistics on that.

I think that the 2 square feet on the ground comment is accurate, since the ball could hit him anywhere. I would need to figure out a reasonable estimate for a human child's volume, and then create a cubic volume for the yard/house. You are correct; I am lazy!

Marcus

[larrybud]

I would NEVER buy a house on a golf course, kid or no kid, that is pin high with the green.

The only house I would ever buy is one which is behind a tee box and is nowhere near an approach shot. Even then, I'm betting that every once in a while you get some drunk a** launching a ball in the direction of the house.

[Skaffa77]

Even though the probability of your child getting hit is extremely low, I would agree with others that severity of the potential impact isn't worth it. I've seen plenty of houses that seem out of reach or impossible to hit if a golfer was actually aiming for the fairway, yet those house still end up with golf balls.

A personal couple experiences that I didn't think would be very probably, but made me realized that sometimes crap happens even when it doesn't seem very likely:

[list][*]On one day a few years ago, I hooking 3 tee shots into the same house in almost the same place (one right after the other). I didn't hook a shot before those tee shots and didn't hit a hook that day after that experience. My group allowed me to drop a ball near near the OB line so I wouldn't chance my 4th shot hitting a window.[*]Earlier this year during my first round, I was hit in the eye by a small rock that ricochet off an iron shot. I got a nice swollen black eye and loss of vision for 5 days. I have no idea how probably that would be, but during my second round this year, I had another smaller rock that ricocheted off my iron shot and hit just above that same eye (under the eyebrow). Now, during my round today (fourth round), I had some VERY small rocks and dirt kick back up under my sunglasses and hit that same eye. Thankfully, the debris was very small and didn't do any damage. In my 11 years of playing golf, I've never had anything ricochet at my eyes outside of some dust...[/list]
As we saw from Marcus, there are many smart people who can provide the statistical significance of an event, but for some reason, I've found that the human element always seems to surprise me (in good and bad ways).

[Liquid]

Why don't you go talk to the person that lives next door closer to the tee. I'm sure he could give you details on if his house ever gets hit or not.