Does closing the Great Highway cause an increase in traffic accidents?

Updated on Tuesday, July 23, 2024

A car speeds on a beach

There is some debate in San Francisco at the moment around permanently closing the Great Highway to traffic.

This road was closed during the pandemic and I regularly visited with my kids to enjoy a bike ride in a safe and beautiful environment. There were also 'slow streets' dotted around the city, many of which persisted. These still have cars and parking and are much less compelling.

Opponents of the plan are concerned that traffic displaced from the Great Highway will make neighborhood streets more dangerous. The hope is that this traffic will shift to Sunset Boulevard but the reality is likely some increased traffic in the Outer Sunset. This seems like a reasonable complaint, but so far I haven't seen any data. Since August 2021 the Great Highway has been closed weekends, holidays and Friday afternoons. Is it possible to see the impact?

I downloaded injury accident and fatality data from Data SF.  This covers the entire city so I first cut the data set down to an area bounded by the Great Highway and Sunset Boulevard (including both) and Lincoln Way and Sloat (excluding both). I then picked a pre period from May 28, 2017 to February 29, 2020 and a post period from September 1, 2021 to June 4, 2024. Both periods are 1,008 days which is 36 28 day periods. Here's a chart of injury accidents (number of people injured in total) by week day:

The good news is that injuries are down overall. Monday through Friday the total decrease is 26%. When the Great Highway is closed at the weekend the number of injuries decreases by 44%. It looks like the streets have got safer when the Great Highway is closed. Before the pandemic you would be 14% more likely to get injured at the weekend, for the last few years this has flipped to 14% less likely.

I also looked at deaths. There are only two, both in the post period. One was on a Saturday and one a Monday. That's not enough data to try and draw any conclusions.

Given how nice that stretch of road is, I'm now a big supporter of the Great Highway Park concept.

In case it's useful here's the code behind the analysis:

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(Published to the Fediverse as: Does closing the Great Highway cause an increase in traffic accidents? #politics #sanfrancisco #greathighway Analysis of data from DataSF shows injury accidents are lower when the Great Highway is closed to traffic. )

Time to go, Joe

A presidential debate between two skeletons

I just sent this note to my senators (Padilla and Butler):

"Being a presidential voter in California is like playing the Trolley Problem without a lever. I know my vote won't make much of a difference, but I can no longer vote for President Biden. I was an enthusiastic supporter in 2020. I'm grateful that Biden defeated Trump. I'm proud of the work this administration has done to reduce carbon emissions, make healthcare more affordable and increase domestic semiconductor production.

While impressive, these accomplishments are sunk benefits. If Trump is allowed to prevail in the 2024 election much of this good work will be undone. That will likely be the least of our problems as a country. President Biden is now almost certain to lose the election. We are currently stuck with everyone realizing that this is true, but too few willing to make their position public. We risk a catastrophic election result unless a landslide of hard truths are delivered in the next few days.

Biden ran on a platform of being the bridge to a new generation of leadership. He must fulfil this promise and start the process of passing the torch immediately. As my representative please take a public position that this must happen as I'm sure you must privately believe. Thank you."

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(Published to the Fediverse as: Time to go, Joe #politics #election #biden Open letter to California senators Padila and Butler )

San Francisco Budget - The Missing Manual

The city of San Francisco made from origami dollar bills.

I recently released my San Francisco Budget GPT. This is based on open data from DataSF, and while it can answer many questions it helps to have enough context to know what to ask. The published dataset has a data dictionary but it can be frustratingly vague. As well as the downloadable data there is a helpful site where you can generate some reports. This post should help fill in some of the gaps.

Overview

Budget data is available from the 2009-2010 to the 2024 to 2025 fiscal years (which run from July 1 to June 30). In the file the fiscal year is at the end of the period. Every dollar has a source and a use, there is a 'Revenue or Spending' column that is Revenue for sources and Spending for uses. The actual dollar values are in a 'Budget' column. There are three hierarchies that allow you to analyze the data - organization, object and fund. Each hierarchy has three levels, and each level has a code and a description. For the rest of this post I'm using data from the 2023-2024 fiscal year.

The total budget for 2023-2024 is $14.6 billion dollars. That's a little hard to put into context. On the one hand it's about two dimes for every week the universe has existed. On the other, it's only a quarter of Elon Musk's Tesla bonus.

Organization Hierarchy

This is the organizational structure of the city - Organization Group, Department and Program. One example is Public Safety, Police, Operating. Here's the full Organization Group and Department structure:

Organization Group and Department

(A quick note on charts - there is a lot of information to present here. Each chart has a full screen button at the top right and I recommend using this to see the most detail. Charts also have tooltips and so you'll have a much better time with this post if you use a big screen and a mouse. On sunburst (nested pie) charts click any segment to filter to that parent only.)

I haven't included Program here. It sounds like it should be useful, the data dictionary says: "For example, the Police Department has programs for Patrol, Investigations, and Administration." But it doesn't:

Police Department Programs

Maybe this worked at some point, but it's not a lot of help for the current year (It's a bit of a mystery, but not like that time I found out someone redistricted the Farallon Islands.)

It's also helpful to know that the department code has been prefixed to every department. So in the data the Police Department is 'POL Police'. This doesn't seem to happen elsewhere in the dataset. It probably helps to find monstrosities like 'MTA Municipal Transprtn Agncy' because we presumably can't find the spare change for longer column names.

Object Hierarchy

My favorite hierarchy is what we're spending money on at a reasonably granular level, broken down into Character, Object and Sub-object. This works both ways and you can look up sources as well as uses. An example on the revenue side is 'Fines, Forfeitures & Penalties', 'Traffic Fines', 'Traffic Fines - Parking' ($98 million).

Character, Object, Sub-object for Revenue

Character, Object, Sub-object for Spending

Sub-objects for the Police Department

While Program doesn't work, Sub-Object allows us to break down Police department spending in more detail:

Fund Hierarchy

Last but not least the fund hierarchy is where the money comes from. The three levels are Fund Type, Fund and Fund Category. As with objects you can also use this on the Spending side to see where funds are being spent.

Fund Type is critical to understanding the budget. There are three main buckets - General Fund, Enterprise Funds and Special Revenue Funds. Enterprise Funds are for self funding departments, so while $1.2 billion of the budget is for San Francisco International Airport that's not coming out of my pocket. The General Fund is discretionary spending and Special Revenue Funds are dollars that have been restricted to specific uses, for example by the endless ballot measures that San Francisco and California are so fond of.

Fund Type and Fund

This treemap shows the first two levels of the fund hierarchy:

Fund Type to Organization Group

Lastly this chart shows the flow of Fund Types to Organization Groups for Spending, excluding Enterprise Funds:

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(Published to the Fediverse as: San Francisco Budget - The Missing Manual #politics #sanfrancisco #budget Detailed guide to the three hierarchies of the San Francisco Budget from DataSF. )

Links for May 2024

Maine joins National Popular Vote

Illustration of Maine

Maine just added its four electoral college votes to the National Popular Vote project. This is a compact between states that will elect the President based on the nationwide outcome once 270 electoral college votes are committed. We're now at 209. Two thirds of Americans support this project. Americans are a sensible bunch and support a lot of things that they will never get until we fix the broken electoral system. Visit my democracy page and do the four things listed there right now.

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(Published to the Fediverse as: Maine joins National Popular Vote #politics #politicalreform #nationalpopularvote #maine #npvic Maine commits 4 electoral college votes, we're at 209/270, and four things you can do help today. )

Links for March 2024

Updated on Sunday, March 31, 2024
InfoWorld: White House urges developers to dump C and C++

Developers urge White House to dump Electoral College and supermajority cloture. #politics #electoralcollege #cloture #c #c++

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The New Yorker: What Have Fourteen Years of Conservative Rule Done to Britain?

"In messages during the pandemic, he referred to ministers as “useless fuckpigs,” “morons,” and “cunts.” The inquiry’s lawyer asked Cummings if he thought his language had been too strong. “I would say, if anything, it understated the position,” he replied." This is a depressing but definitive read as we wait for the UK election to be announced. #politics #uk

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TDCommons and the Future of Patent Law

An illustration of a patent figure for some Hello World generation

Paresh Dave in Wired writes about TDCommons.org, a Google funded but bepress operated site. The idea is to publish technical disclosures as prior art that might invalidate future patents. It's an interesting overview of the subject, including a USPTO attempt to do the same thing (I covered this here) and a commercial competitor, IP.Com. Apparently USPTO is looking for help with this problem:

"Google is hoping TDCommons has a chance to be embraced as Kathi Vidal, a tech patent attorney who was sworn in as director of the USPTO almost two years ago, settles into her role. Deciding that generative AI programs can’t be patent holders has been a higher priority, she says, but creating a better search tool for prior art is an issue she’s discussed with a lot of organizations. Vidal says she’s open to the USPTO administering and funding its own prior art repository, offering up her email, [email protected], for feedback on how to do so."

I'm not super-convinced that she's providing her actual email address, but when I have a few minutes I might suggest my own plan - issue all patent applications and shift the examination to the start of any litigation or enforcement attempt.

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(Published to the Fediverse as: TDCommons and the Future of Patent Law #politics #patents #uspto Prior art attempts like TDCommons, IP.com and even the USPTO's failed scheme should be replaced with a fundamental overhaul of the patent system. )

San Francisco and California March 2024 Ballot Measures

Kids learning Algebra

While waiting for the horror of Weekend at Bernie's vs. A Clockwork Orange in November there is time to contemplate another slate of job-outsourcing ballot measures. Just one for California and seven for San Francisco so it could be worse. Here goes...

California Proposition 1, Behavioral Health Services Program and Bond Measure

Yes. This funds housing and treatment for the mentally ill, homeless and veterans in need. It also requires counties to put more of their existing funds into housing.

San Francisco, California, Proposition A, Affordable Housing Bond Measure

Yes. $300M in bonds to build, buy and repair affordable housing. Homelessness is driven by a lack of affordable housing. In addition to building more I'd love to see us cut more of the red tape, but this is a necessary measure to meet our existing obligations.

San Francisco, California, Proposition B, Minimum Police Staffing Amendment

No. I voted against minimum numbers in 2020, and I don't see a good reason to bring them back today. I also recoil at the thought of a dedicated police recruitment tax as this measure suggests. Funding the police is a very basic city service, as is determining the appropriate staffing levels at any particular moment in time. I'm not against recruiting more police at all, but this is a bad proposal.

San Francisco, California, Proposition C, Real Estate Transfer Tax Exemption for Properties Converted from Commercial to Residential Use Initiative

Yes. I voted in favor of this tax in 2020. Post pandemic San Francisco has one of the worst return to office rates and a huge decline in retail. We need to rethink what downtown is for and I love the idea of bringing in more universities and more homes. So this is a tax break that makes sense for now.

San Francisco, California, Proposition D, Amend City Ethics Laws and Expand Restrictions on Gifts to City Officers and Employees Initiative

Yes. Tougher ethics rules are needed. Can't find any reason to oppose this package. We have bribing of inspection personnel, theft of public funds, corruption in Public Works, that inspector who inspected his own building, etc.

San Francisco, California, Proposition E, Limit Police Department Administrative Task Time and Increase Use of Camera and Drone Technology Initiative

Yes. Apparently when SFPD decides to chase someone they crash 38% of the time, about twice the state average. This bill would let them chase more people and use drones and GPS taggers to do it. I'd like them to go on an advanced driving course or two, but if you can avoid consequences just by running away then we don't really have a law enforcement system. Maybe I'll regret this in a few years but it seems mostly common sense to me right now.

San Francisco, California, Proposition F, Require Drug Screening for Certain Beneficiaries of the County Adult Assistance Program Initiative

No. It looks like the recipients of most of these funds are not homeless and have plenty of hoops to jump through already. This seems like it would risk making their situation worse.

San Francisco, California, Proposition G, Declaration of Policy Urging San Francisco Unified School District to Offer Algebra 1 to Students by Eighth Grade Measure

Yes. This is pointless as it has no teeth and they're moving this way anyway. I still want to help make the pointless point.

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(Published to the Fediverse as: San Francisco and California March 2024 Ballot Measures #politics #sanfrancisco #propositions #election #california ITHCWY voter guide to the San Francisco and California March 2024 primary election propositions and ballot measures. )

Pew: Two Thirds of Americans Support National Popular Vote

People protesting outside the White House, generated by Dall-E 3

A recent Pew Research Center poll found that 65% of Americans support the National Popular Vote. Even the old ones:

"Younger adults are somewhat more supportive of changing the system than older adults. About seven-in-ten Americans under 50 (69%) support this. That share drops to about six-in-ten (58%) among those 65 and older."

If you find yourself in this majority then here are 9 things you can do today to advance the cause.

It's not just a desire to have a president of the country who represents the will of the country that is currently thwarted. Last year Pew found that:

"Today, a 61% majority of U.S. adults say abortion should be legal in all or most cases, while 37% think abortion should be illegal in all or most cases."

58% of Americans favor stricter gun laws. 57% want the Federal Government to take on health care. 63% support free college.

Why can't we have nice things? Apparently because the founding fathers thought we needed protection from the 'tyranny of the majority'. So you'd expect minorities to be well protected by this system.

Same sex marriage was legalized by the Supreme Court's Obergefell decision in 2015. Public support for same sex marriage was at 27% in 1996 (when Clinton passed The Defense of Marriage Act or DOMA). It's now at 70%. We crossed the 50% line around 2010, when Obama said:

"I have been to this point unwilling to sign on to same-sex marriage primarily because of my understandings of the traditional definitions of marriage."

Our majority tyranny protection system failed, Obama failed, Clinton failed. What carried the day was campaigning that convinced the majority that they were wrong on this issue, and arguably the AIDS crisis humanizing a minority for many people.

I wasn't around for the civil rights movement but I think it followed a very similar pattern. The system didn't inherently recognize the rights of the minority. Support was slowly built in public opinion until the Supreme Court eventually stepped in like someone in 2023 who thinks they just discovered Taylor Swift.

While the founding fathers may not have contemplated gay marriage or that black people might be just people they were clever enough to understand that the constitution was a living document and would need to be amended. We just need to get back into the habit.

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(Published to the Fediverse as: Pew: Two Thirds of Americans Support National Popular Vote #politics #politicalreform #national popularvote 65% support a national popular vote, 61% support abortion, 58% better gun laws and 63% free college. Why don't we have these things? )

Does America Need A Third Party (Again)

Andrew Yang and Daniel DiSalvo, pro and anti the motion Does America Need A Third Party.

Open to Debate just released a podcast about the need (or not) for more parties in American politics: Does America Need A Third Party.

Andrew Yang argued in favor. In fact he thinks the right number is probably five - break the democrats in half, break the republicans in half and throw in his Forward party. There is a great case for the first four of these - see this WaPo article from last year. I've suggested forcibly breaking them up, antitrust style. Another approach would be term limits for parties. Yang is growing on me. Reforming the electoral system is a much better platform than universal basic income.

Daniel DiSalvo argued against the motion. Actually he mostly just said that even if everything is broken nothing is going to change so why bother. I think that's 99% right, but not really in the spirit of a debate.

Open to Debate is a rebrand of Intelligence Squared US, which debated the same issue in 2021. In that case the status quo won the day, probably as it was defended by PJ O'Rourke, however the actual vote was 50% more parties and 40% keeping two. Unfortunately I don't know who won this time because Open to Debate has given up on the competitive format and even spirited questioning. You have some back and forth, and some carefully chosen and curated questions like a Biden presser. The original (UK) Intelligence Squared seems to have given up on the big issues and puts out Burgundy vs Bordeaux and people with a book release to plug. Canada is the only real hope right now with the Munk Debates.

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(Published to the Fediverse as: Does America Need A Third Party (Again) #politics #political reform Discussion of the debate between Andrew Yang and Daniel DiSalvo on the need for more political parties in the US. )