Should you worry about 737 Max 8 crashes?

Image result for southwest 737 max 8 routes


Southwest flies 34 of the 737-Max 8’s, which have twice crashed on takeoff recently (newly delivered planes – not likely a maintenance issue), causing overseas countries including Indonesia and China to ground them.

I recommend avoiding these planes for the next few months while the investigation plays out.  The Americans are simply making too much money to ground them.  That probably means avoiding Southwest, however there is one website that claims you can predict the aircraft type from the route:

  • Las Vegas (LAS) – Houston Hobby (HOU)
  • Washington Dulles (IAD) – Denver (DEN)
  • Milwaukee (MKE) – Phoenix (PHX)
  • Nashville (BNA) – Phoenix (PHX)
  • Dallas Love Field (DAL) – Denver (DEN)
  • Denver (DEN) – Sacramento (SMF)

Besides, their safety record has been nosing downward as they have become a large impersonal corporation like the other carriers.  It is currently #3 in the US.

It follows from crash rate theory that the most likely next-big-series of crashes will be in a high value product.  The 737 is the highest value product of all aircraft, Boeing having sold 6 times as many of them as any other model, and having over 4000 backlogged orders, 5 times as many as any other aircraft.  Despite efforts to make new planes, the 737 still amounts to more than half of Boeing’s commercial business.  The Max 8 is the leading edge of that product, with the most capacity and range and other new “improved” features.  It is therefore the least likely to be stable.

In fact, the 737 is one of the most valuable products of any kind of all time.  Southwest uses them exclusively.  They are entirely addictive, capable of making short and medium hauls and carrying lots of people with little maintenance.  You could say they are addictive to both passengers and companies.  Right up there with tobacco and guns.

For statistical reference, see and scroll down to the table.

James Watson cannot say anything about genes and IQ???

Apparently the discoverer of DNA is not allowed to speak scientific truth about any link between genetics and intelligence.  In a statement that is reminiscent of George Orwell’s 1984: War is Peace, etc., his institute simply declares there is no scientific connection.  Probably because it threatens their funding if they admit there is.  See

I have read many papers reporting study results in this field. The formation of intelligence is definitely directed by genetics. Not only does it not appear in animals which don’t have human DNA, but identical twins separated at birth are more closely correlated in IQ than fraternal twins raised together:

  • Same person (tested twice) .95
  • Identical twins—Reared together .86
  • Identical twins—Reared apart .76
  • Fraternal twins—Reared together .55
  • Fraternal twins—Reared apart .35

The above from

If our society suppresses scientific inquiry when it is at odds with politically correct beliefs, are you content to let that stand? Do you think it will not affect our species negatively?  Post a comment and leave your opinion.  Speak freely.  You are safe here.  No one pays any attention to this blog.  I lead a charmed life in that I can say anything at all and no one pays any attention.

Constitutional Gerrymandering

wealth & population vs voting

In the center is the result of House elections, Nov. 6, 2018.  The voting can be explained very well by two factors, neither of which is ideological:

  1. The coastal results are largely explained by population density.  On the right is a map of population density, with the highest values in dark blue (really more like purple).  These closely correspond the east and west coast results, but not the south coast.  There is a bit of shifting around, with electoral results around the great lakes shifting a bit to the west of the population center, but including it.  And some exceptions.  The “rust belt” highly populated regions went Republican to the east of the Great Lakes, which was no surprise given current Republican policy of capturing these votes through pro-jobs initiatives directed at that region.
  2. The rest of the results are largely explained by poverty, such as South Texas (Rio Grand Valley), Indian reservations in Arizona and New Mexico, and the Mississippi region known as “the Delta” which is not the delta of the Mississippi river, but the area on the west side of the state which is flat low-lying delta of many tributary rivers between Memphis and Natchez, an area in which many former slaves have never “moved on” to other regions where there is more opportunity.  There isn’t much opportunity for anyone there.  I grew up there and left.

Why should people who live densely in cities, obviously preferring it, and some of whom (not all, presumably) choose to reproduce at high rates regardless of opportunity, be allowed to set policy for vast tracts of land sparsely filled with people who prefer greater wealth and more land?  There is no rhyme or reason except that representation of states and districts was encoded in the constitution.

Why should people who prefer their traditional habitat (whether reservation or former slave territory) be allowed to set policy for more aggressive people who move to opportunity?  This is in fact very counter-intuitive, and exists only for the same reason.

I say we change the constitution before policy becomes completely dominated by insect-like city dwellers and poverty-stricken traditionalists who will not move.

Tariffs are 40 times less than sales tax


tariff cost 2018A whole LOT of news stories talk about adverse impacts of the 2018 “trade war” with China on U.S. consumers, and also how businesses will “suffer”.  We throw a fresh light on these two issues.


US consumers spend 12 trillion dollars a year.  That’s 12,000 billion.  Not all of it is subject to sales tax, but if it were, and the rate were 8% as where I live, that would be around 960 billion dollars.  The TOTAL value of a 10% tariff on 250 billion of Chinese imports is 25 billion dollars.  This is one 40th of the sales tax.  Consumers aren’t actually going to notice.  They give 15 times that much to charity.


Some businesses will be adversely affected.  Let’s establish that up front.  Nearly every research paper on cooperation since the 1980s has found that “tit-for-tat” is the most common reliable cooperation strategy.  Only a few strategies undermine it.  A good many papers study the “costs” of tit-for-tat.  The costs are the punishment of non-cooperators.  If someone doesn’t cooperate, then you get into the “tat” phase where you don’t cooperate with them, and this costs both of you.

But if you aren’t willing to suffer the short term loss, then the other side will continue to take advantage of you until you are bankrupt and their slave.  Hundreds of papers have shown this.  The idea there is some magic negotiating bullet that will produce cooperation without willingness to suffer costs of punishing the other side is a utopian fantasy which does not exist in the actual world, outside of ultra-liberal think tanks and dreamy Christmas movies.

American Love-Hate of Free Speech, Elections & Russians


Protesters toppled a mobile spotlight and set it on fire during a demonstration against the scheduled appearance of Milo Yiannopoulos at UC Berkeley on Feb. 1, 2017. The event was canceled after demonstrators removed police barricades and occupied Sproul Plaza. (Bert Johnson/KQED) Story here.


The above photo depicts actions which are not free speech, and are not constitutionally protected.  There are examples which are a bit more ambiguous, which will be interesting discuss.  With the photo I just propose a limit up front to what I’m not going to consider “speech.”  I’m going to call it violence.  Seems pretty obviously so.  It appears intended against property, but things get out of hand intentionally or not.  It is the damage of something by force.
No matter your currently political position, I hope to challenge you with cases that you have no easy answer for, and surprise you with the [likely] disagreement between what you think you believe if asked offhand, and what actions of others you might sympathize with.  We’ll start with free speech from three points of view:
  1. Your view of your own speech.
  2. Opinions about free speech generally when it is not specified who is talking or what they are saying.
  3. Actions (which we assume reflect real opinions, not conversation when asked about opinions) in response to speech to which one is strongly opposed, perhaps about which one has some strong beliefs that aren’t triggered by conversations about general speech.

Not all speech is protected.  Advocating overthrow of the US government is against the law.  See 18 U.S. Code § 2385.  However, it is only advocating the overthrow (or destruction) of the government by violence that is illegal.


You can advocate changing the government or disbanding it through lawful elections, and that is perfectly fine under our constitution.


Do you believe in free speech when you are expressing your opinion?  Well, obviously yes.  Do you ever withhold your opinion, and why?  One might withhold one’s opinion out of fear of losing friends, losing a job, or mob retaliation.  You might think of yourself as merely expedient, or truly cowardly.  I merely point out these possibilities.


Do you believe in free speech generally?  Here is how to tell.  Do you vote for politicians who complain about the speech of others, or protect it even when they disagree strongly?  Do you become upset and perhaps cease communication when someone disagrees with you and seems immune to your reason or logical arguments?  If you answered yes to anything other than voting for politicians who protect it, you do not actually believe in free speech.  If so, I am not saying this is bad, just pointing it out.  It could be good or bad depending on a lot of other factors.  Whether you are “right” or not is only one of those factors, and not really a very big one.  If there were a clearly determinable “right” (or left?) arguable by logic, we wouldn’t be having this discussion.


Do you believe in free speech when people you think are dangerous or have dangerous ideas are speaking, provided they are not in violation of 18 U.S. Code § 2385?


Milo Yiannopoulos is a despicable fellow.  He has been kicked out of every institution of higher learning he ever attended and so has no degree.  He was even kicked out of Brietbart news (for saying sex between 13 year old boys could be a positive thing).  He does not advocate non-electoral changes to the US Government.  He might have been guilty of advocating harassment (online harassment), but that was not the incitement for the photo above.  It was the perceived threat of his political views.


Really? Could a human with Milo’s record convince anyone of anything they did not already believe?  Highly doubtful.  I suspect the people who were responsible for burning the trailer above might not really have been afraid of Milo, but of others who would come after him.  Ann Coulter perhaps.  They wanted to send a message.


Since I’m asking you questions, here are my answers.  I’m always in favor of my speech, but find I often get in trouble for it.  I try to keep my mouth shut sometimes, but here is this blog to prove I don’t.  I do not actually believe in free speech generally.  But my reasoning is not easily understood within the usual context of political debate.  I believe, for example, that a group of people have the right to govern themselves as they see fit, including not allowing that government to be changed by those they feel are outsiders, even (especially) by political processes.  This is a freedom.  Take it away and what you have is eventually totalitarianism, because when sufficiently many views accumulate in the population there will be no other way to govern.  But lacking much hope of changing the US Constitution to that effect, especially lacking a convenient definition of insiders and outsiders, and finding myself not in agreement with many who would be insiders, I’ll stick to the constitution for now.


Now lets discuss elections.  This is where it gets dicey.


Do you believe in elections?  When your party wins?  The other?  Someone you consider dangerous in some way wins, but they seem to have broken no laws, you just really don’t like what they say and do, even though their followers approve?  (I could be talking about John Kennedy as easily as Donald Trump.)
What about elections in foreign countries?  Should we try to influence them?  What should we do when someone we think is dangerous is elected?  Should we back non-constitutional removals of foreign governments.
The US has caused removal of foreign governments by covert means many times.  In 1953 Churchill and Eisenhower decided to overthrow the democratically elected government of Iran.  That didn’t end well for us.  I’m sure you can find many more examples.  Presidents of both parties have engaged in this risky behavior which undermines elections and usually results in military rule for a while, and a backlash later.
The US advocated that governments resign during the Arab Spring.  Although this is obviously non-electoral, it was done in the name of supporting democracy.  Later, when the citizens of Egypt voted in an election to change their government back, the US opposed that electoral process.  The US demanded the “removal” of Assad in Syria, and this led to a bloody 9 year civil war and gave ISIS a chance to become established in the country.  So even non-covert interference in other nations has blow-back.
The US this week voiced support for an election in Zimbabwe which appears likely to cause turmoil in the country.  Does that indicated we have learned a lesson?  Consider that:
  • Obama went to England during the Brexit campaign and made threats regarding trade with the US unless Brexit was defeated.
  • Trump went to England during the Brexit negotiations and made threats regarding trade with the US unless Brexit was fully implemented.


Hardly seems we have learned any lesson.

Are the public pronouncements of presidents a more ethical and less damaging way to interfere in the affairs of other countries?  They are more like “free speech” than covert operations.  But they seem to have bad outcomes in most cases.


Should private US citizens interfere in or even express opinions regarding elections in other countries?  Soros brags about causing the change of several East European countries toward more open Western style liberal democracies.  Every one of them is not changing back of their own accord, even though most are already in the EU.  In other words, it simply didn’t work.  And in Ukraine his results had disastrous effects.


Should US foundations which are fronts for government funds operate pro-democracy movements in other countries?  Many have done this, e.g. McCain’s foundation in Russia, now barred for meddling in 2012.  The result appears to have been covert Russian meddling in a US election, so that didn’t really work either, in fact it totally blew up on us because the Russians are hard to thwart.  I should know, I’m married to one.


Let’s talk about Russians and fake news.


So, do you believe in free speech for Russians?


Now that is really the question, isn’t it?  This thing with liberals and conservatives in the US is just politics as usual.  Now that it is benign, it has erupted into riots on occasion and one Civil War, but the Russians pose a moral conundrum.  We cannot justify our covert interference, whether through the CIA or various foundations, while criticizing theirs.


One of the complaints was they were promoting fake news.  There has been fake news in every US election I’ve ever seen.  It used to be last minute flyers direct mailed by the opposition candidate, allowing no time for denial, creating doubt.  It is not criminally illegal to lie if not under oath.  Libel is a matter for civil courts.  It is typically illegal to lie to an arm of the government, or give false information in a contract or financial transaction or when selling something (fraud), but it is not illegal to make up news or rumors.  If someone is damaged, they have recourse to the civil courts.  Otherwise it is just free speech, in which you probably said you believed, but about now you are having doubts.


Now lets talk about the constitution vs what you believe…


What exactly is free speech in the Constitution?  Does it apply only to citizens, or to Russians lying about their identity on the internet?  It is actually tied up with the protection of lying and says nothing about citizenship.  Here is the first amendment, word for word:


Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.


Point by point analysis:

  1. It only constrains Congress, not states or cities.  While most state constitutions have similar provisions, the question of whether the restriction on Congress can be applied to the states is not established.  See here.
  2. Of first concern is that no religion may be prevented.  However, you can bet that 18 U.S. Code § 2385 and various laws about weapons possession, bigamy and child sex laws, and so forth are actively enforced against religions.  This is interesting in the case of Federal laws, but perfectly reasonable in the case of state laws  I personally would like to see prevention of religions such as Islam, not anticipated by the people who wrote the First Amendment, from taking control in elections, regardless of the views of individuals, because I believe they will eventually rearrange the government to make Islam supreme.  This is what the Koran advocates (yes, I have read it, at least enough to make that clear).  We  have enough trouble accommodating different Christian views on death penalty, abortion, etc. without getting into Islam.  It seems perfectly reasonable to do this with state law.
  3. Free speech is covered in the same clause with free press. So, we have established free speech includes the ability to lie, subject to restrictions on fraud and libel.  Does free press include constitutionally protected ability to create fake news?  Apparently so.  Hearst did it to incite the Spanish-American war.  No one put him in jail.  There might be some checks in state law, but not Federal.  If we had a law against fake news, then in ambiguous or disputed situations, who would decide what is fake?  A government censor, appointed by the current supreme leader of course.  This is why we have constitutional protection for lying.  No one knows how to make the slope not slippery.  Is Trump exercising his right to free speech when he complains about the free press exercising theirs and creating fake news?  (Any one with the right to lie invariably does it.)  Of course.  Does he advocate violence?  Of course not.  But the NY Times would like to portray it as resulting in violence, because that might give them a lever to shut him up.  Is this just more fake news?  Probably.  Did violence occur at Berkeley as a result of the left exercising their right to free speech in opposition of Milo?  Definitely.  Will it occur because Trump complains of fake news?  I doubt it, but if it does we will address it, the culprits will be jailed or killed, and a message will be sent no one will forget anytime soon.  Vague and contested predictions of the future are not a basis for legal action.  There can be neither evidence nor proof until time has passed.
  4. Peaceably assemble and petition government is also one clause.  So Berkeley left wing intervention is not protected as it is not peaceable.  A Berkeley professor wrote a blog defending a protest in which white students were blocked from classes.  He defined a protest as creating an inconvenience.  The Constitution does not offer such a definition, and by use of “peaceably assemble and petition” I infer no right to obstruct.  Otherwise “obstruct” or some similar word would be in there.  Even the word “protest” is not in there.  The word used is “petition.”  Ha!  Protests are not protected by the Constitution.  They could be outlawed by states or cities, and in fact “demonstrations” are regulated, require a license, and police control them to minimize “inconvenience.”  If they won’t be controlled, they are declared a riot and people are arrested, sometimes even shot (Kent State).


Having read that, does the organization Patriot Prayer have the right to assemble and petition and engage in other free speech activities, without legal action or non-peaceful (including “inconvenient”) private action against it?  It might help to review the mission statement of PP here.  “Patriot prayer is about using the power of love and prayer to fight the corruption both in the government and citizen levels that seek to gain power through division and deception.


The right to self-defense.


The problem is, when one side dislikes the other so much (i.e. thinks the other side is dangerous in a way that overrides the Constitutional protections) and starts taking “inconvenience” to the level of physical intimidation, pushing, shoving, and all that follows from that including carrying licensed firearms with the attendant possibly of using them if feeling overwhelmed physically and threatened.  What appears to have developed is the following pattern:

  1. Right espouses speech that left considers dangerous and unacceptable.
  2. Left uses a liberal interpretation of free speech including “right to protest to the point of inconvenience and physical intimidation” to discourage and cancel right-wing events.
  3. Right-wingers, unwilling to give up their right to free speech, resort to their right of self-defense.

     N. After some number of steps, violent overthrow of the government results.




The First Amendment applies to “people” acting within the jurisdiction of the US, which includes Russians.  It guarantees the right to lie and create fake news (and to complain about it).  As long as violence is not advocated, it guarantees the right to advocate governmental change.  As long as no campaign contributions are made, there is no requirement to reveal true identities or pass any other ethical tests.  Therefore we may concede every charge leveled at the Russians in connection with recent elections, and even every charge leveled at Trump, and none of them are illegal.  Accepting money and not declaring it (to the election commission if a contribution, to the IRS if income) is illegal, and if those charges are proved people will go to jail.  Paying money to someone to influence their speech, without other coercion?  Merely a business contract.  I am under all sorts of restrictions from my employer about what I can say, specifically about elections.  Generally I ignore it, just as Stormy Daniels did.  The person paying the money may be a fool, but not a criminal.


But the larger issue we were discussing is, do Americans really believe in free speech, and accept its consequences?  Apparently, only their own speech, or only when convenient.

Science & religion – is there a difference?

An open letter to Adam Becker


On 5 April 2018 Adam Becker,  “freelance astrophysicist”  according to his webpage, published an essay on Aeon titled: “What is good science? Demanding that a theory is falsifiable or observable, without any subtlety, will hold science back. We need madcap ideas“.

The article was called to my attention by Firefox Pocket.

Aeon is, according to its about page, “a registered charity committed to the spread of knowledge and a cosmopolitan worldview“.  It is not a news organization and there is no peer review so it is not a scientific journal.  Authors are not generally solicited but hand picked by the editor, so there is no democratic (or actually even cosmopolitan) aspect of article selection.  I have nothing at this point against Aeon, just clarifying that it is a sort of edited collection of blogs founded by Paul and Brigid Hains of London, and that being a registered charity it is tax exempt, so it escapes the tax burden that you and I pay when expressing our ideas.  It can completely write off its expenses.  I cannot write off any of my idea-expressing activities, not even the very high paper publication fees which can run to $3000.  Brigid is the editor, and is an “environmental historian” according to an interview with Frost Magazine.

I wondered exactly what “cosmopolitan worldview” is.  According to Wikipedia, cosmopolitanism is an “ideology that all human beings belong to a single community, based on a shared morality“.  In other words, it is a kind of religion (aka ideology), which supports something closely akin to globalism.

That was my complaint about Becker’s article.  Allowing unverifiable scientific theories makes science indistinguishable from religion.  Religion is just a theory about how the world came to be and our role in it which cannot be verified by scientific experiment.  This means the gatekeepers are priests and dogma, ultimately.  The gatekeepers of science are anyone who can scrape together a credible, repeatable experiment.

You do not have to have a  PhD to be a scientist.  Albert Einstein had only a bachelor’s degree, and barely got that.  When he came up with Special Relativity and the basis of quantum theory in 1905, it was terribly embarrassing and “the establishment” quickly set up a program for him to get a PhD.  If you don’t have a priesthood and you start having visions within most religions, they don’t set up a program to get you qualified as a priest.  You are branded a heretic.  Ask Joan of Arc about that.

I quickly wrote an email to  Here it is.

Subject: about your Aeon article


You are a little late to the party. GR went into unverifiable territory with the metric assumption in 1915 and almost no one every looks back. Unless someone can produce a working wormhole with both ends accessible in the present epoch, there is theoretically no way to verify the metric assumption. Everything else is embeddable on a homogeneous space in which momentum is conserved, and the only accessible regions (outside horizons) are embeddable in homogeneous time where energy is conserved. The damage is immense, a public waiting on “magic” like wormholes before investing seriously in space travel (eccentric billionaires excepted, thankfully). I have spent ten years researching this and my tour-de-force paper has been accepted and will appear shortly. Drop me a note back if you would like a link to it. Science without verifiability is religion, pure and simple. There is, unfortunately, no space to comment on your article. I think that is cowardly.

If you are happy with science being religion, I have already annoyed you enough.  If you think it should be different, then express your thoughts via email to Adam at the above address, and tweet @BrigidHains.


Bridge Collapse: Is “What went wrong?” the Wrong Question?

FIU bridge collapseOn March 10th 2018 a one-kiloton bridge was privately constructed across an 8-lane freeway in Miami in a record 6 hours.

On March 15th it established several new records, failing catastrophically after only 5 days, killing 6 (the toll may rise) by crushing them and their cars on the freeway below.  The blame game and finger pointing has now begun.

As author of a book on crash rate theory, I realized I should make a comment.  So I waited for the first signs of data.  No, I will not wait for every last scrap of data.  For two reasons:

  1. You do not have every last scrap of data when designing and constructing the bridge, and that is the time to act, before the disaster not after.
  2. No NTSB investigation ever prevented a crash.  Something else does, and it is not operative here.

I realize my #2 statement is shocking, but bear with me.  I’m going to take #1 first.

Crashes can only be prevented beforehand.  There are no dead bodies and crying relatives and grandstanding politicians (Marco Rubio in this case) giving urgency to the cause.  There are only accountants taking away duly budgeted funds for margin and testing, and managers and customers calling for the highest value at the least impact.  Solid data to prove there will be a crash is non-existent.  Designers, constructors and customers need to have methods that survive the accountants and managers, in short the economic pressures.

A dramatically valuable technology like 6-hour construction of an 8-lane spanning bridge might itself increase risk of a crash, or virtually guarantee it, and countermeasures have to be deployed.  If you leave valuables on the street, thieves will take them.  If you use a lot of energy, entropy will increase.  If you have great ideas, they will fail.  These are laws of nature, despite the insistence by our culture that no idea is bad and no feature or cost-saving has consequences.  Read the book to see what you can do about it.  In fact, the company that understands this will reach the optimal risk operating point first, and make the most money.  That is why the book has the awkward title of Economic Optimization of Innovation and Risk.  Yes, I linked my book twice in one blog post.  This is a book blog, in case you didn’t get that.

The book emphasizes test and inspection as cost effective means of achieving the optimal risk goal, much cheaper than paying for crashes or just paying too much for capabilities.  It mentions continuing to test after deployment, and that is what prompted this blog post.  The bridge in question seems to have failed during a stress test applied after it was built and the road underneath opened to traffic.

What I said in the book was to leave test data gathering systems in place, and continue to look at the data and make appropriate adjustments.  Not to place artificial test loads on an operational vehicle or structure or system while endangering the public.  There is a very great difference.  And I didn’t want my statement to be misinterpreted.

Ok, enough of that, on to my inflammatory statement about the NTSB.  An NTSB investigation cannot prevent a crash because they only investigate afterward.  Duh.

Hold on.  I know you think they make recommendations and airline operators and manufacturers implement those recommendations, and that prevents future crashes.

It certainly does not.  Quite frequently recommendations, even required ones, are not implemented.  Failure to implement old recommendations is a frequent finding in future crash investigations.  But the airline industry does have a better safety record by some measures than other forms of transportation.  What gives?

What prevents future crashes is fear.  Fear on the part of the public of traveling with operators or on equipment that has had a couple of major crashes.  This fear causes the bad operators or manufacturers from Value Jet to de Havilland to go out of business one way or another.  (Value Jet’s assets were acquired by AirTran, which was later acquired by SouthWest.  Thank about that for a minute.)

Inspections that happen before a crash can prevent a crash.  But only if the results are heeded.  Inspections revealed erosion of the O-ring seals of Shuttle booster rockets, but no corrective action was taken, and the missions were deemed so valuable one was launched on a cold day in January.  That is how feature or mission value impacts crash rate.

In fact, NASA’s three worst disasters in its manned space program, the Apollo I fire, Challenger explosion killing the “Teacher in Space,” and Columbia failure due to ice hitting tiles which had been known for a long time, occurred on January 27th, January 28th and February 1st respectively.

Ice?  February 1st?  So the investigation into Challenger produced what?  Nothing, apparently.  No insight that cold weather affects high performance space vehicles.

Post-crash investigations make people feel better, but they do not prevent crashes.

Regulatory action penalizing operators and manufacturers do not prevent crashes either.  My good friend’s wife was killed by a drunk driver whose license had been suspended for … wait for it … drunk driving.

Test and inspection works.  Breathalyzers that lockout the car’s ignition are imposed by many judges in Texas, but they do not seem harsh enough for MADD, or some Texas judges, and weren’t used in the case of the driver who killed my friend’s wife.  So she is, well, dead.

For quantitative answers, even lacking precise data, about how much to do, read the book.  Why are quantitative answers needed?  Why don’t you just do everything possible?

Try that with any engineering organization.  Engineers and managers quickly figure out they can raise a safety issue and get funding, promotions, etc.  This is why “everybody stay vigilant” doesn’t work.  People only stay vigilant if their vigilance is heeded.  Heeding all vigilance produces a cost bloat and you go out of business that way instead of from public reaction to a crash.  So a mathematical (quantitative) theory is essential.