Wednesday, December 18, 2013

The city's State of Cycling Report: An analysis

Photo from Streetsblog

I referred to the city's bloated State of Cycling Report the other day. Taking a look at the text between all that padding shows how desperate the city is to sell bikes to the people of San Francisco---and how unsuccessful that campaign has actually been, in spite of a lot of help from the local media.

After some preliminary pro-bike blather in the executive summary, page six indulges in the city's unconvincing numbers game about how many people are supposedly riding bikes in the city:

The US Census Bureau’s American Community Survey (ACS) shows a 66% increase in bicycle commuters from 2002 (2.1% of work trips) to 2010 (3.5% of work trips), putting San Francisco third in the nation behind Portland, Oregon (6%) and Seattle, Washington (3.5%) in ridership among major US cities. Annual bicycle counts have more than doubled between 2006 (4,862 riders) and 2011 (10,139) at sampled locations. Two statistically significant random surveys of San Francisco residents during 2011 show that about 3.5% of all trips in the city are taken by bicycle, demonstrating that the ACS, local surveys and bike counts all corroborate one another to show steady increases in cycling.

Playing the percentage game puffs up the increases: Yesterday I ate cereal for breakfast, and I ate cereal again today, a 100% gain in breakfast cereal consumed in only two days!

The 2.1% of bicycle commuters in SF percentage goes back to 2000; pushing it up to 2002 is a bit of petty fudging that only shows how desperate the city is to sell a positive interpretation of these unimpressive numbers.

And the "annual bicycle counts" that "have more than doubled" between 2006 and 2011 are only of bike commuters, not of citywide cycling:

Two statistically significant random surveys of San Francisco residents during 2011 show that about 3.5% of all trips in the city are taken by bicycle, demonstrating that the ACS, local surveys and bike counts all corroborate one another to show steady increases in cycling.

The "surveys" reference is apparently to the MTA's Mode Share Survey that found that only 3.4% of all trips in the city are by bicycle. Though that increase has been "steady," it hasn't been impressive: From 2.1% in 2000 to 3.4% in 2011, a gain of only 1.3% in ten years. The city would trumpet that as a 62% gain, but the rest of us have a right to be unimpressed.

I'll say it again: These numbers are seriously flawed, since the percentage of all trips by bicycle must be higher than the percentage of commuters by bicycle, a subset of all trips by bike. Since the Mode Share Survey methodology seems pretty solid, the original ACS percentage of bike commuters way back in 2000 must have been inflated, thus skewing all subsequent percentages higher than they really are.

This fundamental problem with the numbers is now joined by the city's shocking failure to accurately account for all the cycling accidents in the city by systematically not counting many such accidents recorded at the city's primary trauma center, San Francisco General Hospital. Instead, the city has relied entirely on police reports to calculate the number of cycling accidents in San Francisco.

Page six touches on the safety issue:

The ratio of bicycle trips to bicycle collisions remains constant. Unsafe bicycle riding behaviors (sidewalk bicycle riding and wrong-way bicycle riding) remain infrequent overall and take place on roadways that are deficient in proper facilities.

This is simply untrue. Are they being dumb, or do they think we're dumb? Hard to say. The city's Collision Report on all accidents on city streets says that injury accidents to cyclists are actually increasing, even in the context of the city's systematic under-count of these accidents:

Injury collisions involving bicycles, however, have increased as a share of the City’s reported injury total. From 2000 to 2004, ten percent of collisions involved a person riding a bicycle. Eleven years later that percentage has doubled to 21 percent as bicycle collisions have increased while other types of collisions have not (page 17).

Also according to the city's Collision Report, cyclists are responsible for half their own injury accidents by "unsafe bicycle riding behaviors" unmentioned by the State of Cycling report, like speeding and running stop signs (page 24).[Later: Wrong! Actually the report does mention that behavior on page 40.]

Page 7 continues the behavior falsehood by saying under "Bicycling Behavior" that 94% of cyclists ride legally, only 2% ride on sidewalks, and only 1% ride the in the wrong direction on city streets, as if these were the only serious bad behaviors by cyclists.

More on this report later.

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17 Comments:

At 1:49 PM, Blogger Dave Moore said...

You've said multiple times that the percentage of all trips must be higher than that of commuting. I'm not sure why that would be the case. What makes you think that as a percentage commuters cycle less?

 
At 4:29 PM, Anonymous Anonymous said...

"I'll say it again: These numbers are seriously flawed, since the percentage of all trips by bicycle must be higher than the percentage of commuters by bicycle, a subset of all trips by bike."

What the hell does that even mean.

 
At 4:30 PM, Anonymous Anonymous said...

Oh can't wait for your "more" on this report!!! Sitting on the edge of my car seat.

 
At 4:42 PM, Anonymous Anonymous said...

How many motorists died last year in San Fran? How many did they kill? Crazy if you dont know those #s

 
At 4:58 PM, Blogger Rob Anderson said...

It's not that "commuters cycle less" but that they cycle more---to do errands that others who rely on muni or cars do when not commuting to work. The commuting percentage doesn't include all the trips by bike other than commuting.

 
At 8:23 PM, Blogger Rob Anderson said...

Anonymous said...
"How many motorists died last year in San Fran? How many did they kill? Crazy if you dont know those #s"

Why rush to comment on something that you can easily find out by using the link to the Collision Report---see page 5---I provided in the post? You bike zealots never seem to read anything but Bicycle Coalition press releases and Streetsblog. The least you can do is read the city's documents.

According to the city, fatality numbers have been dropping over time, but that is now in doubt---especially for cycling fatalities---after the UC study found that the city wasn't counting the many cycling injury accidents reported at SF General, the major trauma center for the city.

Presumably the city is now doing some serious thinking about how this happened, what the real numbers are, and what they're going to do from now on.

The MTA will have to eat some shit on this, since they look dumb and/or dishonest for allowing this to happen. And surely one of the results of this scandal will be that their accident reporting system will now include both police reports and the SF General numbers.

Since the cycling accident numbers have been significantly underestimated, it's fair to say that, as I suspected, riding a bike in San Francisco is a lot more dangerous than either City Hall or the Bicycle Coalition have been claiming.

 
At 8:24 PM, Anonymous Anonymous said...

You keep using this word analysis. I do not think it means what you think it means.

"The MTA will have to eat some shit on this"

I will bet you $10,000 that they won't.

 
At 8:31 PM, Blogger Rob Anderson said...

Woof, woof! Pretty safe bet when you're anonymous.

Not surprising you don't know what "analysis" means, since you've never done it before, especially when examining your religion, BikeThink.

 
At 10:32 AM, Anonymous sfthen said...

"bicycle counts have more than doubled between 2006 (4,862 riders) and 2011 (10,139) at sampled locations."

"Bicycle counts" are not "number of bicyclists" as the phrasing tries to imply. A cyclist traveling home from downtown to a hip dwelling in the Mission is counted four times (5th/ Mkt, 11th/ Mkt, Val/ Mkt and Val/ 17th).

 
At 10:45 AM, Anonymous Anonymous said...

Wow--looked at that report. That's a lot of dead people. Why do you think so many people are killed and maimed by cars and what solution do you have to fix that?

 
At 7:08 PM, Blogger Dave Moore said...

As to percentages of commuting cyclers cyclers doing other things: of course cycling commuters do other things, but so do non cycling commuters, and non cycling non commuters. I don't think that means anything about whether the percentage of commuters who cycle is higher or lower than the overall percentage of cyclers. Maybe it's higher. Maybe it's lower. They both have numerators and denominators.

 
At 9:36 AM, Blogger Rob Anderson said...

If riding a bike is your primary transportation "mode," you use your bike for more than just getting to work. You would use it for shopping, other errands, social calls, Critical Mass, etc. Hence, for dedicated cyclists, there are bound to be more trips overall by bike than only their trips to work.

Similarly, people in the city who rely entirely on cars or Muni use those "modes" for trips---shopping, social calls, recreational trips, getting the kids to school, etc.---other than commuting. Got it?

 
At 9:17 PM, Blogger Dave Moore said...

I guess you see something I don't. It is true that those cyclists likely do things other than go to work on those cycles. But many other people who do not cycle also do those things too.

If 1 in 10 people cycle to work, and that 1 also does something else it does not mean that now 20% of all trips are cycle based, or even 2/11. You have to count all the trips done as a denominator. And we don't know that number because all we have is the percentage of commuter trips. It's possible that a higher percentage of all trips is done by cycles. It's also possible that a lower percentage is done by cycles. I don't see how you can tell which it's going to be.

 
At 4:48 PM, Blogger Rob Anderson said...

"You have to count all the trips done as a denominator. And we don't know that number because all we have is the percentage of commuter trips."

This is where you go wrong, Dave. We do have more than commuter trips in the Mode Share Survey that I linked in the post. See page 5.

 
At 2:54 PM, Blogger Mark Kaepplein said...

I wonder what amount of infrastructure investment could yield the 20% bicycling mode share goal? Perhaps being more like Holland, with flat land would help, so flatten the whole city!

Better weather could help, so a dome over the city to only allow rain 3-5 AM is another investment opportunity - make it green with solar panels while at it!

Even getting 20% share of motorbikes in a US city, thus with no pedaling required, is a fantasy. The US isn't Asia, or Holland.

 
At 4:38 PM, Blogger Dave Moore said...

That survey is pretty interesting, although the numbers are small. The takeaways I see are:
1) The mode share for working includes people who don't work and work at home, which when you're trying to figure out who's using the roads seems nonsensical. So the numbers are more like this:
Transit: 47%
Car alone: 37%
Car with others: 10%
Walk: 11
Bike: 5.5%

The numbers for non commute trips only include people leaving the house, so the 4% bike there makes sense, but the question isn't very useful. It asks how the person "usually" reaches other places not how often they use multiple types if they do.

The mode share, trips taken in the last 2 days is more interesting, and shows bikes at only 3%, again lower than the commuting rate.

I still see nothing that indicates that the rate of people riding bikes for non commuting is higher than that of commuting.

 
At 9:48 AM, Blogger Rob Anderson said...

Okay, I give up Dave. But check it out: Do you really think, for example, that people who drive their cars to work don't also use their cars for shopping trips, to the movies, to visit friends and family, etc.?

That's all I'm saying about trips by bike---that those who ride bikes to work also ride their bikes for other trips. All trips in the city by bike (3.4%) can't be the same percentage of commuters by bike (3.3%), which is a subset of all bike trips.

 

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