Auditing mappingpoliceviolence.org, part 2

Following on from my previous post about 2015 police killings of unarmed black people, here's a breakdown of the reasons behind cases 27-52 listed by mappingpoliceviolence.org (MPV).

I've not detailed Samuel Dubose, since there was prosecution of the police officer who killed him (although they gave up after 2 mistrials)

Police did something significantly wrong

1. Kris Jackson (Lake Tahoe, CA): Apprehended by a police officer climbing out of a motel the officer claimed he recognised Jackson as a gang member and thought he might have a gun. Jackson was trying to avoid arrest as he was on probation for selling drugs, but it's not at all clear to me that the officer had any real grounds for opening fire.

Victim shooting seemed justified

1. James Carney III (Cincinnati, OH): Carney was assaulting a woman in a car at an ATM, beating her with apparent intention of robbing her. Police had to Taser him twice - with him still leaning into the car - first time had no effect: he became unconscious and died. One assumes he had some underlying health issue, but police reaction seems very proportionate and justified.
2. Asshams Manley (Spaulding, MD): crashed a car while apparently under the influence of narcotics, ran from the scene. Fought with an officer when caught, apparently went for the officer's gun, was shot once, continued to fight, was tasered, and expired shortly afterwards.
3. Brian Day (Las Vegas, NV): I couldn't find any links for this one (I wonder if the name is correct), but the description from the MPV page indicates the shooting was reasonable: "After speaking to police who were investigating a beating of one of his neighbors, police claim Day went into his apartment and returned with a toy gun. Two officers shot and fatally wounded him after he attempted to 'shoot' them with the toy gun."
4. Salvado Ellswood (Plantation, FL): Homeless man with a history of violence who refused to move when a police officer found him trespassing, became aggressive and struck the office, shrugged off a Taser and then was fatally shot.
5. George Mann (Stonewall, GA): Mann became aggressive and locked himself in a home's garage. Police tried to negotiate with him and used a Taser. Mann became unresponsive and died. Tasering seemed like a reasonable response to this, but presumably Mann had an underlying condition that Tasering made fatal.
6. Freddie Blue (Covington, GA): Blue was one of four men stopped in a car by police. One of the men pointed a handgun at the police, who returned fire. Blue was killed, and one other man injured.
7. Victo Larosa (Jacksonville, FL): Caught dealing in an undercover drug sting, Larosa fled in his car pursued by officers. After hitting 5 vehicles his stolen car was trapped so he ran, pursued by officers. He fell, twisted towards officers and put his hand in his waistband. Reasonably fearing Larosa had a weapon there, the officer shot him.
8. Spencer McCain (Ownings Mills, MD): After a long history of domestic violence calls, police were called again to McCain's house where he had (again) repeatedly beaten his partner. Police heard screaming, forced their way in, and found McCain "making body movements and arm movements that placed the officers in fear of serious injury or death from a weapon that they feared he possessed and would engage them with". This is a bit weak, but McCain did have a previous handgun conviction so it wasn't off the wall to assume he was armed. He was shot to death by all three officers.
9. Kevin Bajoie (Baton Rouge, LA): Police responded to reports of a fight, found Bajoie lying on his back when he suddenly jumped up and attacked one officer. Police had to Taser him repeatedly to stop. He collapsed and later died, probably due in part to the methamphetamine, amphetamine and synthetic marijuana in his system.

Clearly an accident

1. Felix Kumi (New York, NY): hit by a stray bullet in an otherwise justified self defence shooting by an undercover cop. The city rightly paid $1.1M in compensation, which seemed a bit low to me but in the ruthless calculus of compensation Felix was 61 years old so had limited future earnings.
2. Billy Ray Davis (Houston, TX): Arrested after behaving erratically and clearly being in severe mental distress, Davis repeatedly fought with officers even when handcuffed. He suddenly collapsed and was taken to hospital but died. Death probably related to hypertension. No suggestion of wrongdoing on the part of the officers.
3. Jonathan Sanders (Stonewall, MS): Stopped while exercising his horses, there was an argument between Sanders and the police officer which escalated to a fight. The officer applied a in-policy choke hold, but this combined with Sanders' situation of acute cocaine toxicity to cause fatal asphyxia.
4. Zamiel Crawford (McAllah, AL): Led police on a high speed chase after suspicion of robbery. His SUV eventually spun out and slammed into a wall. Police took him to the hospital but he later died.
5. Jermaine Benjamin (Vero Beach, FL): Arrested after being high on something called "Flakka", causing him to be disoriented, aggressive and combative. Police arrested and handcuffed him, but he quickly collapsed and died despite being given CPR. He had known heart problems, which couldn't have helped matters.
6. Kevin Higgenbotham (Trenton, NY): Arrested after he called police who arrived to find him fighting with a neighbour. They had to pepper-spray him before arresting him, but he went into cardiac arrest after transportation to a hospital, and died after being in a coma. There was also concern that he was improperly restrained in hospital though strictly speaking that's not a police issue.
7. Ross Anthony (Dallas, TX): Tased by police after acting erratically by running into traffic and banging the windows of nearby businesses, Anthony was cuffed and arrested, but showed signs of medical distress and was taken to hospital where he died.
8. Richard Gregory Davis (Rochester, NY): After driving erratically and crashing his pickup - twice, Davis got out of his vehicle at police urging but then charged the police and was tased. He received medical attention at scene but was pronounced dead at hospital. There were a large number of contributing factors to the death according to the autopsy report.
9. Curtin Jordan (Huntsville, AL): Police arrested Jordan at his house after being called out by his wife as he was acting irrationally and threatening people. He threw coals in an arresting officer's face. They handcuffed him, but he had a medical issue and was transported to hospital where he died a few days later.

I dunno

1. Darrius Stewart (Memphis, TN): After being detained but not arrested for a broken headlight, Stewart's name came up as having outstanding warrants. When the officer went to arrest him there was a struggle, video evidence showing Stewart as getting the upper hand with the officer, and the officer shot Stewart twice. A federal review found that there was insufficient evidence to prosecute, though Stewart's family have filed a couple of lawsuits, one of which is still open.
2. Albert Davis (Orlando, FL): After a fight at a pool party, police were called to the apartment complex. An officer tried to talk to Davis and a fight broke out; the officer used Taser and then shot Davis. I can't find any information on any subsequent investigation.

Something needs to be done

1. Christian Taylor (Arlington, TX): Loaded with marijuana and LSD, Taylor was apprehended by a sole rookie police officer in a car dealership where he was wrecking the cars. Other police officers were waiting outside but the rookie went in, there was a confrontation, and he shot Taylor as Taylor approached him. The shooting itself is somewhat understandable, but the officer should not have gone in alone, and was later fired; the family was paid $850,000 in a wrongful death lawsuit.
2. Troy Robinson (Decatur, GA): Robinson was a passenger in a car that police tried to stop for a license tag violation. After a chase, the car stopped and the occupants ran. Robinson was tasered while climbing an 8 foot wall, fell and broke his neck. You can argue that he shouldn't have run, all else being equal, but tasering someone climbing a wall (and running away) was rather reckless and against police department guidelines.
3. Michael Sabbie (Texarkana, TX): Died in jail after being restrained by officers. Had a number of health conditions known by the jail when he was admitted. The restraint situation may have been reasonable, the lack of health monitoring and follow-up checking was clearly not. A federal lawsuit was settled in favour of Sabbie's family, correctly.
4. Sandra Bland (Waller, TX): Committed suicide in jail after being arrested for a very minor driving offence that apparently escalated way past what it should have due to the police officer's aggression. While Bland chose to take her own life, it can't be ignored that she wouldn't have been put in that situation if the police officer had been more reasonable.

Evaluation

Of these 26 cases we have:

• 9 where the shooting was justified,
• 9 accidents,
• 4 where there seems to be a need for improvements even if the police officers weren't strictly at fault,
• 1 where police were at fault and charged, and 1 more where they seem clearly at fault,
• 2 where I have no idea due to lack of information.

So that's 6 police-at-fault cases out of the 24 where we have enough data to make an evaluation. The accident-vs-justified balance is a bit different to the first 26 cases we looked at, but it's still consistent with our initial findings. We're on track to have only 25% of the cited 104 cases from 2015 actually being the fault of police.

Taser does seem to be a recurring theme in the accidents - it's a lot safer for everyone than gunplay, but it's certainly not perfectly safe. For the cases needing improvement, again we have a clear need for police officer training in de-escalation - and monitoring of prisoners' health in jail post-arrest.

28 hours of racial lies

One of the latest bits of social justice posturing is the play "Every 28 hours", a project produced by the Oregon Shakespeare Festival:

Every 28 Hours is a national partnership focused on the widely shared and contested statistic that every twenty-eight hours a black person is killed by vigilante, security guard, or the police in the United States.

Regular readers will know that a maths-based arse-kicking is coming. But perhaps, disregarding the numbers, this play is still a compelling work? After all, Harold Pinter was a complete arse, but his plays could still pull in the crowds. Might it be the same here?

The Every 28 Hours Plays consist of 72 one-minute plays inspired by the Black Lives Matter movement, with participation from artists across the nation.

OK, maybe I'll save myself the price of the ticket and just gently gouge out my eyes with a spoon.

One black person killed every 28 hours is 312 black people murdered a year. This is 312 murders too many, no matter who's doing it - and, let's be clear, I'm not quibbling with this . However, let's put this in some numerical context, shall we? I'm assuming that the "Every 28 Hours" authors are mostly liberal arts majors, so I promise to go slow and show my working. (Which, I'd guess, is a sight more than they do.)

The Facts

I'm using the FBI 2015 crime figures, specifically Expanded Homicide Data Table 6 (Race, Ethnicity, and Sex of Victim by Race, Ethnicity, and Sex of Offender, 2015).

Race/Ethnicity of victim	Total	Race of offender
		White	Black / African-American	Other	Unknown
White	3,167	2,574	500	49	44
Black / African-American	2,664	229	2,380	13	42
Other race	222	60	34	126	2
Unknown race	84	34	20	6	24

The other key stat is that, as of 2010, 12.6% of Americans are black or African-American - 1 citizen in 8. I'm making a leap of faith that this fraction has not changed significantly in the past 6 years. Since white people are about 63% of the population, they outnumber black Americans 5 to 1.

The Math(s)

The obvious stat that leaps out - though is hard to state grammatically: white people kill approximately as many white people as black people kill black people. White-on-black and black-on-white killings are actually relatively infrequent. This is also true for the "other" racial category (Asian, mixed-race, Native America etc) which turns out to be a similar fraction of the US population as black / African-American, but only about 7% of the number of racial colleagues killed even if you incorporate the "unknown" category.

So we could produce a companion play "Every 220 Minutes" representing the time interval between one black person killing another black person. We could also write "Every 17 1/2 hours" for a black person killing a white person, and "Every 38 hours" for a white person killing a black person.

But wait! If we have to wait 38 hours for a white person to kill a black person, and a black person is killed by a vigilante / security guard / police officer every 28 hours, doesn't that mean that some of those vigilantes / security guards / police officers must be black (or other ethnic minority)? Why yes, it does. I wonder if "Every 28 Hours" brings out this aspect of the statistics.

The truly terrifying stat is simply that black Americans kill about the same number of people as white Americans despite being outnumbered 5:1. The fear of young black American males held by many white people is visceral rather than statistical - the rate at which black people kill white people is about what you'd expect given the relative proportion of population - but black people in the 20-29 age range should be fucking terrified of black males aged 17 to 24 because they are the ones doing most of the killing of victims in that age range.

Why in the name of all that is holy are the "Every 28 Hours" folks talking about (white) police officers as a deadly influence, when young black men do 10 times more killing?

The Weasels

Let's go back to the Every 28 Hours claim:

...every twenty-eight hours a black person is killed by vigilante, security guard, or the police in the United States [my italics]

Now why, do you think, they added those two extra categories? If they could say:

...every twenty-eight hours a black person is killed by the police in the United States

then wouldn't that be a more powerful message? Perhaps they're not using it because it's not true. The Washington Post reports 258 black people killed by police in 2015. If "Every 28 Hours" used that figure as its basis, it would be called "Every 34 Hours" instead.

The statutory ad hominem

"Every 28 Hours" producer Claudia Alick is big on artistic direction, with a minor in hip-hop coaching, but it seems that her MA from NYU and BA from GWU have not equipped her with the ability to do math. Or perhaps she has the ability, but also gained the power to ignore the figures for the greater good of spreading propaganda. She certainly doesn't seem to be concerned with actually improving the lives of, and reducing the horrific body count in, the black American community in any meaningful way.

Dodgy assertions from CASH's head medic

The salt-haters have been praising the reduction in dietary salt for an important role in the 42% fewer stroke fatalities and 40% drop in those dying from coronary heart disease:

The researchers, who include Britain's leading campaigner against added salt in food, claim that diminishing levels of salt was "an important contributor" to falls in blood pressure over the eight-year period. "As a result, the decrease in salt intake would have played an important role in the reduction of stroke and ischaemic heart disease mortality during this period," say the authors.

"Would have played"? That's a funny way of saying "was shown at a 95% confidence level to have played"... Co-author Graham MacGregor is the chair of CASH; his daytime job is Professor of cardiovascular medicine at the Wolfson Institute of Preventive Medicine at Queen Mary. So surely we can expect a rigorous and impartial analysis of the data from him.

If I'd been looking to prove or disprove this assertion, I'd have looked at stroke and heart disease rates in a range of patients over this time frame, where I had some objective measure of salt in their diet (urine samples), and looked to see whether patients with lower salt levels (in a group of patients with otherwise similar exercise, age, gender, racial stats) were correlated with lower stroke and heart disease rates. Is this what they did?

Patrick Wolfe, professor of statistics at University College London, took issue with the authors for assuming that the improved blood pressure seen in the 2003-2011 was largely the result of reduced salt intake. "Plausibility of assumption does not equal evidence," he said.

Oh. Apparently not, then. That's a piss-poor basis for the claims CASH (and international co-conspirator WASH) have been touting around about salt reduction. As commentor ID4968047 notes this reduction in strokes and heart disease could equally have come from the reduction in smoking in the past 10 years - the obligation is on Prof. MacGregor to show otherwise. Looking at CASH's writeup of the paper (the link to the paper isn't available yet, looks like) they say:

Confounding factors that were looked at include age, gender, ethnicity, education, incomes, alcohol consumption, fruit and vegetable intake and BMI.

Exercise and smoking are not mentioned. Nor do they reference the increase in statin use - and indeed Aseem Malhotra from Action on Sugar claims that statins are harmful and don't reduce mortality which is interesting as they seem to be a prime competitor to CASH/Action on Sugar's crusades against sugar and salt. Malhotra's claims got panned for lack of evidence by Prof. Rory Collins from Oxford.

It seems that others in the medical stats community have doubts too:

David Spiegelhalter, professor of the public understanding of risk at Cambridge university, cited the researchers' admission that the fall over that time in systolic blood pressure would be expected to reduce strokes by just 11% and heart attacks by 6%, small amounts of the total falls. [my emphasis] Reduced blood pressure did not represent the authors' claimed "substantial contribution" to the reduced death rates.

This is not to say that Graham MacGregor is obviously wrong in his claims. They might be true but it is a real reach to claim that this study supports them. And if this is the best he can do, I'd suggest the Marcela Trust / OMC Investments crowd who are backing CASH find someone with a better stats background to organise their crusade against salt and sugar.

Update: just managed to dig up the link to the full text in BMJ Open. From a quick look the focus was on linking salt reduction with BP reduction but not explicitly with stroke/CVD reduction.

The authors themselves admit:

It is likely that several factors, that is, the fall in BP, total cholesterol and smoking prevalence, the reduction in salt intake and the increase in the consumption of fruit and vegetables, along with improvements in the treatments of BP, cholesterol and CVD, contributed to the decrease in stroke and IHD mortality.

They have a stab at isolating the effect of salt by casting tea leaves:

it was estimated that a 2.7 mm Hg reduction in systolic BP that occurred with salt reduction would be predicted to reduce stroke by approximately 11% and IHD by 6%.

but even then the 2.7mmm Hg reduction figure they quote is the net over 8 years including factors such as decrease in smoking and increase in statins, so to attribute it to just salt reduction is "optimistic". They appeal to studies in Japan and Finland in the late 60's / early 70's but the huge gaps in time, diet and environment between now and then render the comparison unconvincing. If that's the best argument they've got to offer, I'd hate to see the ones that didn't get selected for use in the paper.

The conclusions are what kill the paper for me:

The reduction in salt intake is likely to be an important contributor to the falls in BP in England from 2003 to 2011. As a result, the decrease in salt intake would have played an important role in the reduction in stroke and IHD mortality during this period. [my emphasis]

That's a terribly weak conclusion even to my relatively untrained eyes. If they could state this more strongly, they would. Instead, they reserve their strength for polemic:

... the mean salt intake in England (8.1 g/day in 2011) was still 35% higher than the recommended level of 6 g/day, and 70% of the adult population (80% men and 58% women) had a daily salt intake above the recommended level.[14] Therefore, continuing and much greater efforts are needed to achieve further reductions in salt intake to prevent the maximum number of stroke and IHD deaths.

Reference 14 doesn't justify the 6g/day level, it's just a measurement of sodium levels. The authors don't make any reference I can see to why the recommended level should be 6g/day and not (say) 10g/day or 3g/day. If you're appealing to magic figures in your conclusion it doesn't give great confidence in the rest of your article.

Racism by association

I appreciate that if someone wants to get paid for a "all Tories are racist" article then the first instinct is to head to The Guardian, but it would be nice if the editors imposed at least some kind of quality bar. I refer, of course to Lola Okolosie's piss-poor piece in today's edition: "Yes, you can have a Chinese girlfriend and still be racist":

[Tory candidate] Edward de Mesquita complains that he has had to fend off recurring accusations that his party produces "racist" polices. His strategy? To remind constituents that "Conservatives are not racist." The proof? Well, erm, "so many of the Conservatives have foreign wives after all".

Okolosie's text drips with scorn as she recounts this conversation, but my sympathies are actually with Mr. de Mesquita. After all, how can you prove a negative: that you are not racist? There are undoubtedly racist (by any reasonably narrow definition, say "openly prejudiced against people with an African or West Indian background) Tories, as there are racist Liberals, Labourites, Quakers, preachers and atheists. If I were to claim, for example, that BME English teachers are racist - undoubtedly, some of them are - and ask Ms. Okolosie to show that BME English teachers are not racist, how could she do so? It's not her fault that I'm asking a stupid question.

She helpfully lists six reasons why you can have a wife/husband/boyfriend/girlfriend/best friend from a BME background and still hold racist views or prejudices, including that you might:

[...] subscribe to the exotification of BME women which casts south-east Asian women as docile, demure and able to "treat a man well" [...]

An interesting prejudice she has there. It's an observable fact that in the UK and USA many of the younger generation of white male engineers have Chinese, Japanese, Filipino or South Korean girlfriends, fiancées and wives. It's equally observable that few white women have CJFK boyfriends or husbands - I've known precisely one female white engineer with a Chinese-ancestry husband. (The Indian male and female engineers seem to be pretty equally cosmopolitan in their choice of partners, by contrast). Having met a number of such couples, the CJFK ladies are significantly more vocal and have more drive than the white men. Perhaps they value the personality and earning potential of the man more than white women do?

Incidentally, Chinese parents seem to have a lot more problems with their daughter marrying outside their race than white parents do - and white fiances seem to be a lot more acceptable than other non-Chinese races. One Indian-Chinese couple I know ended up with the Chinese girl's father boycotting the wedding because her husband-to-be had such dark skin. Filipino fathers tend to look askance at black boys trying to partner with their daughters. I've even known a Filipino girl's father who applauded his daughter marrying a white guy because he thought Filipino boys were no good...

Okolosie also suggests that you may:

[...] believe in the idea of a model minority that is enterprising, while the majority within the BME community need to "pull themselves up by their bootstraps" and get with the programme of what life is like in the UK.

Well, you could look at the financial profile of the various ethnic groups in the UK and discover that Indian families tend to be disproportionally wealthier than black and Pakistani families, with their median wealth pretty close to white families and more than double that of Pakistani families. Either the UK has a weirdly specific racial prejudice that affects Pakistanis but not Indians, or there's some explanation besides simple white racism for black and Pakistani poverty. You can also look at low income in Birmingham and discover that Pakistani, Bangladeshi and black ethnic groups are over-represented in poverty vs population, while white, Indian and Chinese groups are under-represented.

This is not saying that poverty is the fault of black, Pakistani and Bangladeshi families (I suspect that the sharply different economic profile of immigrants has a lot to do with it), but it does at least partially support the assertion that Ms. Okolosie scorns so much. But she's an English teacher, and they are famously scornful of such white patriarchical concepts as "data". (See what I did there?)

Let's assume, getting back to Ms. Okolosie's original point, that the Tories have policies which are objectively bad for the black community - since black ethnicity and poverty are somewhat correlated, policies which negatively affect the poor will likely negatively affect the black community. We might say that such policies are "racist" since they negatively affect an ethnic group. Except that Tory policies tend to support businesses - and hence benefit Indian and Chinese families who tend to work in or own small or medium sized businesses. If we assume that Labour policies benefit the poor but penalise businesses, aren't they racist as well? Indeed, unless you have no policies at all, it's likely that one or more of your policies penalise an ethnic group. So every politician is racist! Even (heaven forfend) Diane Abbott.

Okolosie's label of "racist politician" is hence information-free. Effectively every politician is racist, by her definition.

Anti-discrimination laws may do a lot but they haven't quite yet made us a post-racial society.

As long as self-aggrandising divisive special pleaders like Okolosie (and Al Sharpton, Jesse Jackson, Diane Abbott) are held up as arbiters of correct behaviour, you bet we're not post-racial.

Gaming the system - ambulance response times

It turns out that if emergency services try to chase response times then the public can get screwed over, in a very real and non-reversibly fatal sense:

Emergency services were called at 23:15 GMT and a paramedic arrived within 15 minutes. The paramedic contacted the control room three times asking for the ambulance to arrive sooner, but it did not arrive until 01:00 GMT the next day, Mr Nelson's family said.

Presumably this was a motorcycle paramedic, who will carry some fluids though probably not blood and certainly not more than a few pints of them. The unfortunate 26 year old Mr. Nelson is described as suffering from haemorrhaging, which was almost certainly internal and hence could not be successfully treated without surgery; all the paramedic could do was buy time pending transfer of Mr. Nelson to a hospital with an on-call surgery team, so that Mr. Nelson could a) receive whole blood in volume to replace his loss and b) be opened up so that the surgery team could clamp the offending major blood vessel to stop the loss. Unfortunately it seems that the required ambulance took another 90 minutes to arrive, which was way too late.

So why did the ambulance take so long? We can reasonably assume that the paramedic made a diagnosis of internal bleeding and called in for an urgent transport, so the available ambulances must have been elsewhere:

He added: "It seems that if they meet the target for the whole of the east of England, it satisfies the government target but the danger is they focus on urban areas where they can easily hit the target and rural areas get neglected.

Bingo! Why is this? Here's one possible explanation.

Suppose you have a reasonable-sized city (e.g. Reading, Oxford) surrounded by a fairly large rural area. Your ambulance, fire and police stations are somewhere in the city. At regular times you have a small number (say 2-4) of available ambulances, waiting to respond to calls. Most of your calls will come from within the city as not only do you have most of your people there but they are in an environment more likely to cause accidents (heavy traffic, concentrated drinking etc.) Anticipating this, you station most if not all of your ambulances around the city ring road and near major junctions so that they can either head straight in to the city, head straight out to the rural towns in their sector, or drive around the ring road to access a different sector. Your hospital will be within the city so your vehicles will go "green" (available) there; you can direct them to go straight to the next call or send them to one of your vacant ring-road sectors.

Blakeney, the home of Mr. Nelson, is 80 minutes from Great Yarmouth and 50 minutes from Kings Lynn (the nearest major towns). Without wanting to second-guess Norfolk ambulance control I'd imagine that they might have had an ambulance stationing point near Cromer or Swaffham, but someone else called first and that ambulance was taken; once they received the priority call from the paramedic, the ambulance would have nearly an hour of driving just to reach Blakeney. Because the incident happened on a Thursday night they probably had fewer ambulances available than on the busier Friday or Saturday nights, and because it happened around 11pm it was during the busiest period.

If the East of England Ambulance Trust wanted to reduce the incidence of long waits for ambulances in rural towns, it would have to position more ambulances way out from its major urban centres. The problem is that this would increase response times for the bulk of incidents during busy times when the remote-stationed ambulances were required near the cities. For the sake of significantly improving response times in relatively rare scenarios (multiple incidents away from the cities) you're going to be significantly impinging on your common-or-garden city incidents.

So what's the ambulance response time target?

Immediately life threatening – An emergency response will reach 75% of these calls within eight minutes. Where onward transport is required, 95% of life-threatening calls will receive an ambulance vehicle capable of transporting the patient safely within 19 minutes of the request for transport being made.

The NHS has at least addressed tail latency here ("95% within 19 minutes") but the problem is that this is a national target. It's much easier to meet in the densely-populated southeast than the more sparsely populated areas of the country. In the latter case, an ambulance trust's best bet is to concentrate resources around towns as discussed above, since they won't have a prayer of meeting "75% within 8 minutes" otherwise. It also allows wildly increasing times for 1/20th of the patients - if you can't get an ambulance to them in 20 minutes, there's no additional penalty for taking 90 minutes to reach them despite the fact you're identified these patients as needing onwards transport.

The dominant problem here is a national service (the NHS) requiring national targets for regional services, not making any allowance for the wildly different demographic distribution across the country. There's nothing conceptually wrong with the form of the target, but they need to vary the numbers as populations become less dense. You'd expect the tail latency requirement to remain fairly constant, but the initial response time to increase as population density decreases, and you should also add a 99% latency requirement (say, 30 minutes) to reduce the long waits for needy rural patients. Your response targets may no longer fit within a soundbite, but at least they are now aimed at saving lives across the country.

The difference between government and private industry

The US insurance industry has indicated 50,000 sign-ups for the Affordable Care Act insurance so far. This is less than 10% of what they were aiming for by this time. That's bad enough, but more instructive is how the US Government will officially count enrollments:

When the Obama administration releases health law enrollment figures later this week, though, it will use a more expansive definition. It will count people who have purchased a plan as well as those who have a plan sitting in their online shopping cart but have not yet paid.

Holy crap. Someone must have signed off on this definition, and I'd love to know how they kept a straight face doing it.

David Burge (aka IowaHawk) nails this:

If Amazon included uncompleted shopping baskets as "sales," Jeff Bezos would go to prison http://t.co/inFR4NeEK3

— David Burge (@iowahawkblog) November 12, 2013

The inevitable conclusion to be drawn: the HealthCare.gov enrollment figures are so dreadful that it's preferable to focus attention on a ridiculous definition of "enrollment" than on the number of actual paid-up enrollees.

Deddington NIMBYs

Driving through the small town of Deddington the other day, I was struck (not physically) by a large sign on the wall of a very expensive-looking house as you enter Deddington from the east: "KEEP DEDDINGTON RURAL!"

Now Deddington has always struck me as rather rural - you only go through it as a cut-through between the M40 and Chipping Norton - and indeed it's a good 10 miles from the nearest Waitrose (in Brackley), which is my personal measure of ruralness. But clearly it's in imminent danger of un-rurality, so I did a little Googling. Horror of horrors, Pegasus Group is planning to built 85 houses on a 9.5 acre site in Deddington:

If you feel our village should grow in a more sustainable way, responsive to local needs, with 3-5 new houses a year over the next 18 years as contemplated by the new Local Plan, please make your views known by emailing CDC Planning Department (ref. 13/00301/OUT)

Deddingon parish has a population of 2,100; this probably translates to about 1000 houses, of which probably 400 or so are in Deddington; you're looking at a ~20% growth in the town itself. This is hardly the end of the world. Looking at the satellite view of Deddington, with the area for development being the wedge-shaped field above Hempton Road and to the left of Banbury Road this doesn't look as if it's going to change the town beyond all recognition. If you zoom out a little, it's very apparent just how much green space is around Deddington. Building around there is a no-brainer. In fact, the tedious stretch of road between Deddington and Hempton to the west could also useful be built on, joining them up into one entity. (Now I'm going to get letter bombs through the post from the Deddington Urban Liberation League.)

Arguing for less than 1% growth per annum so that it takes ~18 years to increase town size by 20% instead of 1 year is such painful NIMBYism that deserves at least contemptuous dismissal, and better yet an active increase in the amount of planning permission granted. After all, if the town is going to get so het up about such a modest development, surely the marginal additional indignation for e.g. a doubling of house numbers would be rather small?

Interviewers don't know jack

At least, that's the impression given by Google's HR head Laszlo Bock:

Years ago, we did a study to determine whether anyone at Google is particularly good at hiring. We looked at tens of thousands of interviews, and everyone who had done the interviews and what they scored the candidate, and how that person ultimately performed in their job. We found zero relationship. It’s a complete random mess, except for one guy who was highly predictive because he only interviewed people for a very specialized area, where he happened to be the world’s leading expert.

For anyone who's done any substantial amount of interviewing, this will ring a bell. Without the data following-up on hired candidate performance in their jobs, there's very little that the individual interviewer receives as feedback on their interviewing. If you consistently have 4+ people doing interviewing the same candidate on closely-related topics you can compare their score and identify interviewers who give diverging scores - but then you have no idea whether the outlying interviewer was correct or not. I sometimes wonder whether in these situations companies should hire a small fraction of candidates who score highly with divergent interviewers but moderate-to-low for the rest. Of course, that's an expensive way of stats gathering.

Megan McArdle analyzes the interview and draws conclusions that I think are slightly off:

Resume and past work history are much better predictors of future performance [than brainteasers]. The problem is that in most fields, these are hard to ascertain unless you're pretty prominent.

I take a little more hope from Bock's analysis. I'd agree with McArdle (and Bock) about the relative useless of brainteasers. I would disagree to some extent with the resume and work history as predictors. What resume and work history really give you as an interviewer is a baseline for what to expect of an interviewee's performance, and to give the interviewer a pointer to the work-related questions to ask.

Example: the resume (CV) claims that the interviewee has experience building distributed systems, and has 8 years of Perl development. Immediately you, as hiring manager, know that one of your interviewers should throw a (company-standard) distributed systems development at them, and expect them to nail most of the high points. All interviewers should expect them to be able to write some Perl on demand and expect it to parse, use modern idioms, and employ efficient and suitable constructs. Falling short on any of these indicates that either the resume is "generous" with the facts or that the interviewee does not learn and increase their ability with experience as quickly as could be expected.

To make use of these facts, as Bock notes, you need to have standardised assessments of your candidates - a smallish bank of interview questions with a calibrated range of possible responses. This may well not be the world's best predictor of ability in a job, but at the very least it's a reliable way of screening out the under-performers and the outright resume fabricators.

Reflections on uptime

A couple of conversations this week have made me realise how "uptime", and its unloved stepchild "downtime" are misunderstood in today's world of the always-on Internet. I thought I'd blog a little about this and see where it went. First, the case of fanfiction.net.

This conversation was with a buddy in NYC who is an avid fan-fiction reader. She (and fan-fiction readers are disproportionately "she") was complaining about the site fanfiction.net being down for an hour or two, during which time she was going cold-turkey being deprived of new chapters from her favourite authors. When quizzed further, she admitted that the site was down some time between 1am and 3am NYC time, so perhaps she actually got more sleep than she would have otherwise... anyway, her complaint was "why is fanfiction.net always going down?". So here's my attempt at an answer.

fanfiction.net is hosted by Tiggee, so costs real money to run. The site has some ads - Google's AdChoices - but they seem to be tastefully done and not in-your-face. Neither reading nor uploading fanfic costs anything, so ad income has got to cover the entire cost of running the site. As well as Tiggee's fees for hosting this also has to cover the time and trouble of the site maintainers. Downtime means a loss of ad revenue as well as readership, so the owners are going to want to minimise the downtime but not spend too much money doing so. Assuming 5TB of storage and 30TB/month bandwidth, a sample hosting company like Cloud Media will charge you about $3700/month. Let's assume then that it costs $4000/month to host the site as it stands, and that ads bring in a steady $8000/month in revenue (about $7 / hour).

My friend reports an informal estimate of fanfiction.net being down maybe 4% of the time she checks (ignoring rapid re-checking in the 15 minutes after she sees that it has gone down). This would be costing them $320/month in lost ads. This isn't worth getting out of bed for.

Not all hours of downtime are equal, however. Web browsing follows a roughly diurnal curve: working in GMT - note that summer times skew these results due to some nations not observing daylight savings time - at GMT midnight, which is the trough, people are coming in to work in Japan. If you have some control over your downtime (e.g. for system upgrades) you can schedule it in the window of 5am - 8am GMT when virtually none of your likely audience in English-speaking countries is awake except for die-hard nerds. The opportunity cost of your scheduled downtime is probably halved, or more, so that $320/month loss drops further.

Is it even worth trying to stop unscheduled downtime like this? Your hosting company is already taking care of what outages are in their control (bad hardware, network misconfiguration etc.) and mistakes on their part will result in a refund of your hosting fees for outage time outside their Service Level Agreement. You can probably assume that they'll give your hosted machines something like 99.9% of uptime, which is a little bit less than 1 hour of downtime per month. All you have to worry about is misconfiguration or performance problems of the software you run on their hosted machines, which most often happens after you - the site owner - have made a change. There are occasions when your site falls over spontaneously (e.g. because you've run out of storage space) but they are few and far between. Setting up an alerting system which pages you if your service goes down outside your normal working hours would require a substantial technical and financial investment, and probably wreck your sleep patterns.

The usual way out of this corner is delegation, but here the information economy prices work against you; even a spotty part-time sysadmin who has no idea what he's doing would cost you $2500/month to have on-call. Unless you can pool him with a number of other sites to amortise his cost and increase his utilisation, there's no point parting with your cash. This is why people tell you that adding each "nine" of reliability (going from e.g. 90% to 99% or 99% to 99.9% uptime) increases your costs exponentially - you need new layers of people and systems to a) prevent downtime occurring and b) react extremely quickly when it happens. For situations when your downtime losses are close to your uptime income and costs, it's far better to accept the downtime, fix it during your normal working hours, and be extremely conservative in operating your site within its allocated storage and bandwidth limits. Only make changes when you have to, and ensure you're around and watching closely for several hours after the upgrade.

The conclusion? The reason most "free" websites have a somewhat unreliable uptime (between 1 and 2 "nines" i.e 90-99% update) is that it's simply not economically worth their while to pay the additional costs to be down for shorter durations or fewer occasions. You get what you pay for. Of course, there are situations when downtime costs are not close to operating costs - I'll be addressing that in my next blog.

US and Canadian guns

Following today's awful school shooting in Connecticut I wondered what gun ownership / crime was like in the USA versus Canada. So let's take a look.

• The USA has a population of 311mm versus Canada's 34mm, a ratio of about 9:1;
• US gun owners is 32 per 100 adults vs Canada's 24 per 100 persons (so correct by about 20% to 20 per 100 adults in Canada);
• Total firearm fatalities in the USA: 9,000 homicides, 17,000 suicides, 600 accidents (0.086 per thousand people) vs 200 homicides, 600 suicides, ~30 accidents in Canada 830/34mm (0.02 per thousand people);

So in the USA, despite a gun ownership rate that is not massively different from Canada, you are much more likely to be the victim of gun homicide (5x as likely) or gun suicide (3x as likely), and a bit more likely to be the victim of a gun accident (2x as likely, which is about what you'd expect from the ownership rates). Why then do Americans kill each other with guns about twice the rate you'd expect if they were Canadian?

It turns out that the dominant factors for firearm homicide are race, sex, and age group:

The victimization rates for blacks were 6 times higher than those for whites.
The offending rates for blacks were more than 7 times higher the rates for whites.
Males represent 77% of homicide victims and nearly 90% of offenders. The victimization rates for males were 3 times higher than the rates for females. Approximately one-third of murder victims and almost half the offenders are under the age of 25. For both victims and offenders, the rate per 100,000 peaks in the 18-24 year-old age group.

It looks as if the dominant reason for the firearm homicide rate in the USA is the proportion of young black men. 700K Canadians identify as black (2%) compared to 12% in the USA.

That's not the entire explanation - you don't get school shootings in Canada, and the major school shooting perps in the USA were white (or Korean). But it's a disturbing set of statistics.