Anyone good at calculating probabilities?

Good thinking batman - I think. Will give it consideration on the way home tonight.Cheersian

get an MSR or equal fuel bottleAttention Required! | Cloudflarethey seal tight and will fit in your saddlebags or other carrying case, they are made to take pressure and some banging aboutnow you can purposefully run dry, empty the bottle into the tank and proceed to your favorite stations to fill both.{abe} this is what I used to do with an old VW that had a broken gauge.This message has been edited by RAZD, 09*05*2005 04:47 PM

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It is not unreasonable to suppose a causal element to this - given the frequency of homeward bound petrol outs. This doesn't have to be the case though.The problems with cause as I see it are:- I don't know exactly how many miles I've got left when the needle stops because I don't know when the needle stops to any great degree. I could be any number of miles on since it has stopped before I notice it. I can't be managing things to the extent that would allow me to get things right to within a few miles.- hitting 1/4 tank occurs randomly due to the varying use and driving habits. This should mean I run out in random areas. That I don't might be causal but it might be like tossing a coin 7 times and coming up heads.- I can't remember where I was coming from on all occasions: I was homeward bound on them all that much I know. I can remember 3 of the 7 being coming home from work and one from the pub, but cannot remember route in that morning, exact route home whether or not I nipped out for lunch etc, etc.Cause is reasonable to suppose but only because it appears on the basis of the unique location of petrol outs. The variability of things however suggests no cause. Presuming no cause (because no particular one can be established as far as I can see), could it be worked out what the probability is. 6 outs (forgetting the time where I went looking for petrol)Thanks

I think that there's a bit more analysis to be done (there may be a bit more to it) but the analysis seems to be pretty solid.Remember it's not when you hit the empty mark (quarter tank) that matters - it's when you forget to refill the tank in time. So saying that the point when you hit empty is random really doesn't address the key issue (are there circumstances where you are more likely to forget to refill)Since you only gave us the information for the trip to and from work there's no way that a meaningful probability could be calculated including the other cases. You simply didn't provide the information that would be needed.

Spoken like a true Yank The lifespan of a Harley in Ireland would be about 3 weeks before it got nicked. The 'rice burner' I've got would fit an average sized mouse under the seat and its svelte lines would be ruined by saddlebags. I may be made in Gods image but I ain't quite rid of my own. If it don't fit down my jacket or can't get bungeed to the rear seat it don't come with me

I forget to refill frequently enough - maybe 10% of the time. Rather than being concious of what the situation is, I'm riding along then with a start, realise I must be well into the danger zone, start minding the throttle openings and hunt for a station. That single I went looking but ran out was an example of that. All the other times (bar the 6) I've remembered in time - and not run out. I'd find that there would only be a cupful of petrol sloshing around when I got to the station- showing that I was very close to a run out.I couldn't say what would cause me to forget. Given the route I take, total concentration is required. It's like doing point duty in a war zone. My mind would never be dawdling on non-riding stuff. I think I forget because the system relies on remembering all the time what the state of play is with the gauge and that I can't accurately know what I have left. If I lose track of it for whatever reason then forgetting is a potential. But I couldn't see a pattern to it.The times it's happened have varied. I imagine all have occurred in the evening, sometimes its been dark sometimes bright. I would consider myself an evening person for best concentration (bible study, designing things etc) so wouldn't reckon fatigue plays a part)As far as the other cases go, it would be reasonable to suppose the same density of stations as with the work route. The route back home from anywhere I usually go would for the most part involve 3 of the garages that are included in the work route. And most routes would involve built up areas with a similar density of garages. It would be safe enought to presume this in order to get a reasonable degree of accuracy I suppose. (The only route I would go which would take me away from this arterial route, would be to my mothers. Aprox 20 miles with 7 stations on route including the first 2 of my work route)

Well there is a pattern in the times that you do run out, and that's why you're asking for the probability to be calculated. Isn't it reasonable to look for a cause rather than just assuming that it's pure chance ?And something you seem to be missing. The shorter the route the more likely you are to run out near that particular station - even if it was completely random.

I'm not against eliminating elements that would reduce the problem to one of which calculated the probablity of running out on a 36 mile round trip with a 1/3 mile range after runout with 6 garages.Its just that a pattern of where I end up doesn't necessarily indicate a particular cause. It could do, it is more likely that it should - but not necessarily. It's hard to imagine a cause given that there is such randomness in where I fill up.The main cause would be a work route trip which started from home on approx 1/4 tank (as likely as any other gauge indication so would occur frequently enough), didn't fill on the way (trhis does happen - so is consistant as an additional factor) and forgot to fill on the journey home (unlikely but does occur). If the approx 1/4 tank wasn't enough I would run out on the way home. 6 times would be about right given that I would tend not to forget for more often that I do forget - for obvious reasonsThis cause however would apply to anywhere where approx 1/4 tank was reached. If I started out from work this way and followed the above causes, I would run out close to work the next day. The cause seems equally applicable to wherever 1/4 tank occurs. Why would I only forget on the return journey of a 1/4 start from home. I've no idea This would be true if short routes typically took me in the direction of that station. They don't however. That station (1 mile from home) is at the start of a motorway which is the artery which is used for about 8 miles before I'd begin to deviate into work, Dublin city, friends. Other local routes: shopping, church, friends, family etc lead me in other directions which take in stations not on the work route and include the station around the corner - which I've never rolled into.For me to roll into this station 6 times on the homeward leg means I would have come up the motorway. If 3 of the six were work journeys and 1 was the pub (which is at my friends, 13 miles away) given the 2:1 ratio of work/pleasure miles, then 2/3rds of the remaining 2 unknowns could be assigned a work distance and 1/3 a (motorway related) pleasure distance (friends, Dublin city thus 13 miles) and a petrol station frequency taken from the work route - given reasonably consistant density of them all around me

Well you seem to be contradicting yourself. According to an earlier post:

quote:

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The route back home from anywhere I usually go would for the most part involve 3 of the garages that are included in the work route.

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That's not very likely if most of your shorter trips only go near 1 of them.And although your filling uip may be fairly random that doesn't mean that there isn't a common factor in the few occasions wen you have run out.But to do a simple (and wrong) calculation, based on the assumption that where you run out is random:1) There is a stretch of 1/2 mile near each station where you xan start to run out and still make it in (1/3 mile before and 1/6 mile after).2) With 6 stations there are 3 miles (6 x 1/2) where you can run out near a station.3) The probability of running out close enough to a station is therefore 3/18 = 1/64) The probability of running out near a specific station is (1./2)/18 = 1/365) The probability of running out at the same station at least 6 times out of 7 is therefore:
(7 * 1/6 * (1/36)^5 * 31/36) + (1/6 * (1/36)^6)
= 218/(6^13)
= 1.7 * 10^ -8Less than 1 chance in 50,000,000Of couse the fact is that those are only the occasiosn where you forgot to refill in time, so it is very likely that there is some reason why you forgot to refill on those occasions and it is related to the fact that it is that stationrather than nay of the others.o

However the odds of 1 in 50,000,000 are so outrageous that I can confidently say it never happened.

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Aslan is not a Tame Lion

Unless you are imitating creationist arguments it would be better to say that the assumptions underlying the calculation don't reflect the reality.Which is also true of the occasions when creationists actually bother to reference calculations. So far as I can tell they usually don't bother to even do that.t

What, reality should override theory?

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Aslan is not a Tame Lion

Creationists and ID'ers seem to have problems understanding THAT one.Although I wouldn't dignify a rough estimate made under questionable assumptions with the title "theory"

It could be seen as a contradiction or it could be seen as an attempt to give the relevant information in as concise a form as possible. As transpired, I gave the relevant details for the sitation as it related to the run outs. What happened happened. I'm not making it up. You were right to look for cause as this would result in another model for which to find the probability of (which would inevitably more probable). I can't see one that would be particular to running out where I run out - but don't say that there isn't one.Thanks Paul for your taking the time to investigate and work it out

Tell that to all the lotto winners