Recently our car was broken into, despite being parked in what I thought was a relatively safe place. While getting the broken window replaced, I learned that a key consideration when designing car windows is that they shatter safely, so as not to injure passengers. Car windows are not primarily designed to keep the crooks out; in fact the police officer who inspected our car was surprised that the burglars apparently needed to hit our window more than once in order to break it.
A corollary is that car windows are easy to replace. If you design something to break, you might as well make it easy to swap. Many car windows are apparently held in place by just two little hinges (as is ours) and the entire replacement process takes 15 minutes.
What this means is that you are probably better off paying for optional “glass insurance” than you are for a better car alarm system. If someone wants to break into your car, the alarm is not going to stop them. It might even lead them to damage the door or other parts of the car that are more expensive to repair than the window 😉
In Australia, even “comprehensive” insurance packages do not usually cover damage to windows or windshields. In our case this is an optional extra that costs around $60/year. It turns out that each window costs around $200 to replace (the deductible is typically around $500). So at least to me, this seems a worthwhile extra to pay for.
In today’s headline news, the Auditor General reports that the crime rate is falling on Melbourne’s train system (e.g., see here and here). The number of incidents has remained roughly the same, while the number of commuters has gone up. So, the Transport Minister says there is more crime but the trains are safer . The Auditor General seems concerned that “Victoria Police had failed to carry out promised pilot projects designed to minimise passenger perceptions of danger on railway stations and trains”. Shouldn’t they be catching crooks instead of manipulating customer perception?
Well, if we want to play this game of statistics, here are a few additional things to consider. Many crimes probably go unreported raising questions about data reliability, but lets put that aside for a moment. The Age reports that the crime rate on Melbourne’s trains is 33 per million passengers. I did a quick web search and wow! that figure seems to be pretty high. In Boston last year there were 827 major crimes on the MBTA system out of 350 million trips, making that only 2.2 crimes per million, way below the 33 in Melbourne. Even if we only consider assaults as “serious crimes”, which TheAge reports is 17% of the incidents, that works out to 5.6 assaults per million trips. I don’t have time to find data for lots of other cities, but it appears the New York subway carries over 10 million passengers/day and sees only 5.6 crimes per day, while on the Washington Metro it is about 4.35 per million riders. Is Melbourne’s train system really that safe?
A more sensible approach is to accept that crime happens on the train/subway systems of every major city, and to try and tackle the problem. Statistics could be used constructively. For a start, explore the distribution of criminal activity. Melbourne’s trains radiate outwards from the city center and some train lines go through neighborhoods that are much more crime ridden than others. So we should be looking at the rate of criminal activity on each line separately instead of the average across the whole system. Even better, identify the location and type of criminal activity in each line segment and station, and do data mining to figure out behavioural patterns. This should inform counter measures, e.g., by putting officers on duty, adding surveillance cameras, anticipating risky situations, etc. This way, the Police might even earn the respect of commuters, instead of just hoping to manipulate their perceptions of safety.
After teaching a class last night during which we discussed substitutes, I realized that the recent eruption by Eyjafjallajökull, while sad for all involved, presents a good teaching example. The exogenous elimination of air travel led predictably to a scramble for substitutes. Eurostar ran out of capacity and quadrupled their ticket prices; a black market also naturally emerged. Meanwhile bus companies, facing more rivals than Eurostar, kept the same price but temporarily boosted the number of buses they ran. Taxi drivers cashed in on customers including John Cleese who paid $5000 for his ride. I couldn’t help but reflect upon our trip to Japan last month, where we enjoyed riding on the Shinkansen bullet train. The ride was quick and smooth, there were no long waits at security lines and elaborate rituals at airports, legspace was ample, and our electronic equipment did not have to be switched off during takeoff and landing. Air travel is overrated.
Today, an anonymous guest post (from someone with an ANU connection) ponders airline pricing.
A recent article in the SMH reports that from February 1, Air France and KLM will begin charging obese passengers 75% of the cost of a second seat if they cannot fit into one seat. This story re-ignited an interesting question I’ve had regarding airline tickets. I have always been perplexed by the issue of pricing after a trip to the Middle East.
After spending far too much money on carpets in the souks, I arrived at the check-in counter at the airport to be told that my ticket only allowed 25kg of baggage and that my recent acquisitions had sent me 5kg over. If I wanted to take them with me, I had to pay the surcharge. The exact amount escapes me, but I was told it was to cover the cost of transporting the extra weight.
What puzzled me about the explanation was that standing at the next check-in counter was a sizable chap (possibly around 110kg) with 25kg of luggage. He wasn’t charged excess since his luggage was on the allowable limit, but if the price of a ticket represents the cost of transporting weight; your weight, surely his net impact on the overall weight of the plane is far greater? (I’m an average male, 175cm tall and weighing around 78kg). With my luggage, my total weight on the plane was 108kg, much less than the 145kg of my fellow passenger.
Simple flight dynamics says that the heavier the plane, the more fuel it will use to fly. Presumably, most other costs of operating an aircraft are fixed (salaries for crew, catering, landing and docking levies, lease payments on the aircraft), which leaves fuel. If the largest variable cost of running a plane is determined by the fuel used to transport the overall weight (plane, passengers and luggage) of the aircraft at takeoff, surely the current pricing mechanism for airline tickets is economically inefficient?
Wouldn’t it be far more efficient to charge people based on their total weight impact on the plane (i.e. body weight plus baggage)? That way, slim travellers with little luggage do not subsidise heavier people with large amount of baggage.
Any theories as to whether the suggestion of our anonymous poster could – well – fly?
Everyday someone at Google says “wouldn’t it be neat if …” and then it happens. Today’s neat trick answers the question “wouldn’t it be neat if we could see where taxis were before calling the relevant cab company or stepping outside?” For the answer, click here.
Now you can find out the location of any cab and its phone number through the US. This is going to give new meaning to the movie line: “follow that cab.” You can now literally do it, ’24’ style.
A new paper in the Journal of Political Economy by Aaron Edlin and Pinar Karaca-Mandic looks at the harm other drivers are causing you (in terms of higher insurance premiums). Here is the abstract: Continue reading “It’s the other drivers, stupid”