{"items": [{"author": "Todd", "source_link": "https://plus.google.com/112947709146257842066", "anchor": "gp-1356281392718", "service": "gp", "text": "I'm not sure airplanes \naren't\n intrinsically safer. Surely the likelihood of head-on collision is significantly lower, given the same number of passengers (or even just the same number of planes). But the point is well-taken.", "timestamp": 1356281392}, {"author": "Jeff Kaufman", "source_link": "https://plus.google.com/103013777355236494008", "anchor": "gp-1356282310840", "service": "gp", "text": "@Todd\n\u00a0We're \nreally\n careful with planes. \u00a0Think about the amount of inspection they get, their redundant systems and other safety features, and how much training pilots go through. \u00a0While they're not likely to hit things while flying if they break they're way up in the air. \u00a0Plus takeoff and landing are tricky.", "timestamp": 1356282310}, {"author": "David German", "source_link": "https://plus.google.com/111229345142780712481", "anchor": "gp-1356284621292", "service": "gp", "text": "@Jeff Kaufman\n they're way up in the air, but the failure mode is gliding. ", "timestamp": 1356284621}, {"author": "Alex", "source_link": "https://www.facebook.com/jefftk/posts/406782932729430?comment_id=406846379389752", "anchor": "fb-406846379389752", "service": "fb", "text": "Also remember the factor of you driving vs. someone else driving. People overestimate their own driving skills.", "timestamp": "1356285859"}, {"author": "BDan", "source_link": "https://plus.google.com/103775592027106438640", "anchor": "gp-1356290465158", "service": "gp", "text": "@David German\n Gliding is only the failure mode for one type of failure (engine failure). There are other types as well (control systems, sensors, landing gear, etc.). And even if you can glide, you have to have somewhere to glide \nto\n, which needs to be pretty close when you're rapidly losing altitude.", "timestamp": 1356290465}, {"author": "Adam Yie", "source_link": "https://plus.google.com/114873051319510815414", "anchor": "gp-1356295454216", "service": "gp", "text": "@David German\n\u00a0\"they're way up in the air, but the failure mode is gliding.\"\n
\n
\nThat doesn't just hold for prop planes and tiny jets? Statistically they're safer already, but that makes me feel more secure about typical commercial flights.", "timestamp": 1356295454}, {"author": "Pablo", "source_link": "https://plus.google.com/105467680319054692970", "anchor": "gp-1356296944267", "service": "gp", "text": "I agree that this is a reliable rule of thumb. \u00a0I'm not sure it is particularly useful, though. \u00a0There are not that many different modes of transportation, and we have good accident data for all the major ones. \u00a0By spending a couple of minutes inspecting a table listing the odds of dying in different transportation accidents, we can get most of the information we need, making the heuristic largely irrelevant. \u00a0Here is one such table:\n
\n
\nhttp://www.medicine.ox.ac.uk/bandolier/booth/Risk/trasnsportpop.html", "timestamp": 1356296944}, {"author": "Jeff Kaufman", "source_link": "https://plus.google.com/103013777355236494008", "anchor": "gp-1356322832886", "service": "gp", "text": "@Pablo\n: that table is on a population basis, which isn't helpful when making choices. \u00a0But I agree with your larger point, which is that this observation isn't compressing that much data.", "timestamp": 1356322832}, {"author": "Jeff Kaufman", "source_link": "https://www.facebook.com/jefftk/posts/406782932729430?comment_id=407048862702837", "anchor": "fb-407048862702837", "service": "fb", "text": "@Alex: I've never found the \"overestimate your own driving skills\" claim very convincing. People have varying ideas of what makes a good driver (get there fast, be safe, smooth ride, minimal gas use). So I may think I'm an above average driver on the combination of metrics I think are important while you think you're an above average driver on a different combination of metrics.", "timestamp": "1356323334"}, {"author": "Jeff Kaufman", "source_link": "https://plus.google.com/103013777355236494008", "anchor": "gp-1356323792688", "service": "gp", "text": "@Todd\n\u00a0Another reason to think planes aren't inherently safer than cars: general aviation (smaller planes) is a good bit less safe than driving. \nhttp://www.meretrix.com/~harry/flying/notes/safetyvsdriving.html", "timestamp": 1356323792}, {"author": "David Chudzicki", "source_link": "https://plus.google.com/106120852580068301475", "anchor": "gp-1356331210741", "service": "gp", "text": "+Jeff from that link, it seems link airlines have slightly more fatalities per mile than driving? I'm really surprised. ", "timestamp": 1356331210}, {"author": "Jeff Kaufman", "source_link": "https://plus.google.com/103013777355236494008", "anchor": "gp-1356364579288", "service": "gp", "text": "@David Chudzicki\n\u00a0That surprises me too. \u00a0Made a followup post: \nhttp://www.jefftk.com/news/2012-12-24\n\u00a0", "timestamp": 1356364579}, {"author": "David Chudzicki", "source_link": "https://plus.google.com/106120852580068301475", "anchor": "gp-1356374216797", "service": "gp", "text": "Ah, right -- thanks Jeff. Lucas, I think Jeff's latest poInta to the numbers I meant. ", "timestamp": 1356374216}, {"author": "Kiran", "source_link": "https://www.facebook.com/jefftk/posts/406782932729430?comment_id=407430289331361", "anchor": "fb-407430289331361", "service": "fb", "text": "http://www.science20.com/.../flying_or_driving_which_safer", "timestamp": "1356398446"}, {"author": "Jeff Kaufman", "source_link": "https://www.facebook.com/jefftk/posts/406782932729430?comment_id=407453299329060", "anchor": "fb-407453299329060", "service": "fb", "text": "@Kiran: your link is confused.
\"I would argue that the two modes of travel can't legitimately be compared. Why not compare flying with swimming? or hiking? However, since the safety argument is invariably made regarding flying and driving, it is this tacit assumption, that one is so fundamentally safer that it is beyond questioning, that I am challenging.\"
We want to know the stats for flying vs driving (or taking the bus) because that's what we need when making choices. You don't choose between flying to NYC and swimming or hiking.
While it's not \"beyond questioning\", this person doesn't question it well.
\"It is also important to consider what constitutes a fatality in these statistics. Clearly when an aircraft crashes there's little doubt about the fate of the passengers, however in automobile statistics this isn't as clear-cut. Once again, using the 2005 statistics, there were 43,510 people killed1, however nearly 6,000 of those were pedestrians or bicyclists. While this is certainly an unfortunate statistic, it can hardly be argued that it is a result of the mode of travel (unless one wants to criticize walking).\"
You shouldn't count pedestrian (or other non-passenger) fatalities, yes. But you can still compare passenger-fatalities per passenger-mile, and it's way in favor of flying. See today's post: http://www.jefftk.com/news/2012-12-24 (As they bring up in the footnote, you should also exclude motorcycles, and in the stats I calculate I do so.)
\"From a safety perspective it can hardly be argued that safety is increased based on the number of passengers (since the risk isn't carried individually). The risk is intrinsic in the actual distance traveled, so it doesn't matter if the flight is full or empty when quantifying this value.\"
What? Imagine we had a technology that connected cars together into a train without any effect, positive or negative, on the risks. What was \"100 miles traveled\" for each of 100 cars now becomes \"100 miles traveled\" for a single car-train. Calculate fatalities-per-vehicle-mile and you see a huge change, but there was no change to the underlying risks. Calculate fatalities-per-passenger-mile instead and you rightly see no change.
\"automobile accidents tend to hold relatively steady from year to year, whereas aircraft fatalities can range from zero to several hundred, even with only one accident occurring. As a result, it isn't really fair to compare the two values to each other, since any choice of aircraft fatalities is clearly arbitrary and can radically change based on the period being examined.\"
You can deal with this by averaging over enough years. Even in the worst years (ex: 2001) for planes they're still way safer (per passenger mile) than driving.
\"the simple reality is that we use our cars far more often than we fly and as a result, we incur a greater risk because of it.\"
While this is true, if I'm making a decision about whether to drive or fly it doesn't matter that I already have large exposure to driving-risk. The relevant risk is the increased chance of death with driving over flying.", "timestamp": "1356403764"}, {"author": "Kiran", "source_link": "https://www.facebook.com/jefftk/posts/406782932729430?comment_id=407460339328356", "anchor": "fb-407460339328356", "service": "fb", "text": "The whole subject is confusing. I was actually looking for another article when I found that.", "timestamp": "1356405952"}]}