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Can you solve Seth Godin's math problem?

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Re: Can you solve Seth Godin's math problem?

#11

Post by modoc »

mnemonicsloth wrote: post #5

The premise is flawed. We start with: Let's say your goal is to reduce gasoline consumption. And then we start talking about fuel efficiency. IIRC, though, it's pretty well established in the economics literature that increasing fuel efficiency doesn't reduce gas consumption much, if at all. Increased fuel efficiency means lower effective gas prices, which people respond to by driving more. The net effect is about th…

The problem with increasing the price of gas is you hurt the poor most of all. Honestly, jacking up the price of gas isn't going to change my driving habits at all, but doubling the cost of gas (for example) will absolutely impact the budget of a lower income person who is commuting to work in an older car. They can't afford a newer car, they can't afford to move closer into the city, and there isn't public transportation available. They have no options other than to cut back on things like food and braces for their kids, etc... (sure some folks blow lots of money on cigs, big screen tvs, beer, etc... - but honestly the majority of people who are just scraping by, are doing their best).

Figure out how to make it affordable (while being safe) for people to live closer into major cities, and you'll have a real impact on gasoline usage.

Re: Can you solve Seth Godin's math problem?

#13

Post by 3pt14159 »

jws wrote: post #3

If we americans worked in gallons/mile instead these sorts of decisions would be obvious and intuitive. No one goes out with the goal of burning a gallon of gas so measuring how many miles you can go by burning one is silly. mpg is the reciprocal of what they want and people are bad at reciprocals. I fixed his problem below: Suburbans: 23.5 liter/100km Priuseses: 4.7 liter/100km Suburban+: 18.0 liter/100km (save 5.5…

I live in Canada where we typically get both mpg and liter/100 km. I've found that, almost universally, my friends that report mpg have less fuel efficient cars than the ones that quote liters per 100 km when asked about a vehicle's fuel efficiency.

I tend to think that one of the reasons that Americans tend to have less fuel efficient cars is that when they are evaluating alternatives 9 mpg and 10 mpg are "closer" or more equivalent than 47 mpg and 50 mpg. For example, if I go out and buy a Truck in Canada I could either compare

Ford F150: 15.7 liters/100km (15 mpg) city, 11.2 liters/100km (21 mpg) highway.

GMC Sierra 2500 4WD: 14.7 liters/100km (16 mpg) city, 11.76 liters/100km (20 mpg) highway.

With the Sierra, you are using a full liter less of gas during city driving at the cost of only half a liter of highway driving, so unless I'm doing more than 66% of my driving on highway like conditions, I should go with the Sierra, but that information does not come across to gas conscious buyers that use mpg.

Re: Can you solve Seth Godin's math problem?

#14

Post by pingswept »

mnemonicsloth wrote: post #5

The premise is flawed. We start with: Let's say your goal is to reduce gasoline consumption. And then we start talking about fuel efficiency. IIRC, though, it's pretty well established in the economics literature that increasing fuel efficiency doesn't reduce gas consumption much, if at all. Increased fuel efficiency means lower effective gas prices, which people respond to by driving more. The net effect is about th…

I think you're basically right, but I wonder about the details.

For example, my own driving is not money-limited-- gas could double in price and I would drive just as much, because I drive so little already. Whether I pay $200/year or $400/year for gas doesn't make a difference.

I suspect that the vast majority of miles driven are driven by people who would find cheaper alternatives, like buses or bicycles or email, if prices went up even 20%. But that's just speculation. Empirically, when gas costs doubled briefly last year, it seemed to me that traffic was still almost as bad.

So, I mostly agree with you, but I'm not 100% convinced.

Re: Can you solve Seth Godin's math problem?

#15

Post by mmt »

JimmyL wrote: post #4

The root of the problem is that we shouldn't be thinking in miles per gallon - we should be thinking in gallons per mile. The follow-up problem is that average person think miles per gallon is linear (as they would phrase it, "the difference between 1MPG and 2MPG is the same as the difference between 60MPG and 61MPG") because they don't know any better, whereas it's really an inverse/reciprocal relationship. I wrote…

I'm going to agree with another commenter, however, that the "saving fuel" premise is flawed.

Personally, I like MPG because it makes the range-on-a-tank-of-fuel calculation much easier, and I care much more about range than about fuel economy.

I was sad when it turned out the original Honda Insight didn't get 70MPG, because, otherwise, it would have been interesting due to the 700 mile range.

Re: Can you solve Seth Godin's math problem?

#16

Post by JimmyL »

mmt wrote: post #15
JimmyL wrote: post #4

The root of the problem is that we shouldn't be thinking in miles per gallon - we should be thinking in gallons per mile. The follow-up problem is that average person think miles per gallon is linear (as they would phrase it, "the difference between 1MPG and 2MPG is the same as the difference between 60MPG and 61MPG") because they don't know any better, whereas it's really an inverse/reciprocal relationship. I wrote…

I'm going to agree with another commenter, however, that the "saving fuel" premise is flawed. Personally, I like MPG because it makes the range-on-a-tank-of-fuel calculation much easier, and I care much more about range than about fuel economy. I was sad when it turned out the original Honda Insight didn't get 70MPG, because, otherwise, it would have been interesting due to the 700 mile range.

I'm curious - why the fixation on range of a tank of gas?

If we're talking about serious off-road vehicles, then I can see why you'd want to max out your range to make trip planning easier. But thinking of the majority of drivers doing the majority of their driving (especially in cars like a Honda Insight), they'd be hard-pressed to end up going somewhere that didn't have a gas station at least every 200 miles.

Re: Can you solve Seth Godin's math problem?

#17

Post by mnemonicsloth »

pingswept wrote: post #14
mnemonicsloth wrote: post #5

The premise is flawed. We start with: Let's say your goal is to reduce gasoline consumption. And then we start talking about fuel efficiency. IIRC, though, it's pretty well established in the economics literature that increasing fuel efficiency doesn't reduce gas consumption much, if at all. Increased fuel efficiency means lower effective gas prices, which people respond to by driving more. The net effect is about th…

I think you're basically right, but I wonder about the details. For example, my own driving is not money-limited-- gas could double in price and I would drive just as much, because I drive so little already. Whether I pay $200/year or $400/year for gas doesn't make a difference. I suspect that the vast majority of miles driven are driven by people who would find cheaper alternatives, like buses or bicycles or email,…

my own driving is not money-limited...

Yes, but (I infer that) you're a well-paid, environmentally-conscious professional living in the center of a dense (and expensive) city. For everybody like you, there's a pizza delivery driver on the other side of the bell curve who covers 200 miles a night. If delivery-miles get cheaper, we have no reason to think the pizzeria wouldn't spend the savings on more drivers, so as to reduce the amount of time customers have to wait.

when gas costs doubled briefly last year...

We wouldn't expect to see much change so soon after the price shock. Filling up at $4.50/gallon is no fun, but in the short term it's something people are willing to put up with rather than buying a new Prius or moving into a new home with a shorter commute.

Re: Can you solve Seth Godin's math problem?

#18

Post by roundsquare »

JimmyL wrote: post #16
mmt wrote: post #15

Earlier quoted context omitted.

I'm going to agree with another commenter, however, that the "saving fuel" premise is flawed. Personally, I like MPG because it makes the range-on-a-tank-of-fuel calculation much easier, and I care much more about range than about fuel economy. I was sad when it turned out the original Honda Insight didn't get 70MPG, because, otherwise, it would have been interesting due to the 700 mile range.

I'm curious - why the fixation on range of a tank of gas? If we're talking about serious off-road vehicles, then I can see why you'd want to max out your range to make trip planning easier. But thinking of the majority of drivers doing the majority of their driving (especially in cars like a Honda Insight), they'd be hard-pressed to end up going somewhere that didn't have a gas station at least every 200 miles.

I think its more useful for a lot of people. If you drive to work and back every day, then you know how many miles you drive. So you can say "I need to fill up my tank every week" or something, and you can figure out how much money you need to spend each week. Its not about wondering if you can fill up during a trip, but about how much you need to spend on gas.

Re: Can you solve Seth Godin's math problem?

#19

Post by roundsquare »

modoc wrote: post #11
mnemonicsloth wrote: post #5

The premise is flawed. We start with: Let's say your goal is to reduce gasoline consumption. And then we start talking about fuel efficiency. IIRC, though, it's pretty well established in the economics literature that increasing fuel efficiency doesn't reduce gas consumption much, if at all. Increased fuel efficiency means lower effective gas prices, which people respond to by driving more. The net effect is about th…

The problem with increasing the price of gas is you hurt the poor most of all. Honestly, jacking up the price of gas isn't going to change my driving habits at all, but doubling the cost of gas (for example) will absolutely impact the budget of a lower income person who is commuting to work in an older car. They can't afford a newer car, they can't afford to move closer into the city, and there isn't public transport…

Two things come to mind that might work: 1) Gas credits for the poor... but this might be hard to get right. 2) Cheap public transportation. This won't work everywhere, but I suspect it would work in big cities and their suburbs.
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