Jun 18 2020

Intelligent Life in the Galaxy

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The headlines (taken from the press release) read: “New light shed on intelligent life existing across the galaxy.” But here’s the thing – I don’t think the referenced study does that at all. So what are they talking about?

The study uses their own version of the Drake Equation, which is a way of calculating how many spacefaring civilizations there are likely to be in the universe. The equation itself is correct – you consider the number of stars, the subset of those with planets in the habitable zone, the number of those who develop life, then intelligent life, then technology and multiply all that by the average lifespan of such civilizations. The equation works, as far as it goes, it’s just not terribly useful. The reason is that we don’t know the values of any of the variables. We can guess some of them, those dealing with stuff we can see, like how many planets are out there, but we essentially have no idea about any of the variables dealing with life.

The reason we have no idea is basic scientific logic – because we have one data point, Earth. Remember when we encountered the first interstellar object? That one encounter left us with no practical way to calculate how common such objects were. It could have been a one-off extremely unlikely event. But as soon as we encountered a second interstellar object, we had a rough idea how common they were. We had something to calculate.

You just can’t extrapolate from one data point. We may be the only life in the entire universe, or the universe might be teeming with life – both ends of the spectrum are consistent with our one known data point. We have no idea how common life is, how common intelligent life is, or technological civilizations, or how long they survive on average. None – really. So any numbers we put in are just wild guesses, and the errors on those wild guesses multiply.

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Jun 16 2020

The Stats on Police Killings

During the current national attention being paid to police practice and inequities of police killing of African Americans it is important to put the data that we have into as much context as possible, in order to understand the phenomenon and make sure that our efforts to improve the situation are properly targeted. Unfortunately, the data are complex, which makes it easy to see what one wants to see. I will try to break down the research as objectively as I can, although it is likely that perception of bias will also depend on perspective.

We can start with the most basic numbers:

Risk is highest for black men, who (at current levels of risk) face about a 1 in 1,000 chance of being killed by police over the life course. The average lifetime odds of being killed by police are about 1 in 2,000 for men and about 1 in 33,000 for women. Risk peaks between the ages of 20 y and 35 y for all groups. For young men of color, police use of force is among the leading causes of death.

This same data, from an August 2019 study, also shows that the overall risk of death at the hands of the police is about 2.5 times greater for black Americans than white Americans. This is an often cited figure, and it is salient, but there are additional layers here. Let’s break down the police use of force into non-lethal force, lethal force against armed citizens, and lethal force against unarmed citizens. Some studies focus on “shootings” rather than all uses of lethal force, mostly because that is how databases are often set up, but that can also miss important cases.

There is strong evidence that police use of non-lethal force is greater against black individuals than white. This holds up across a broad range of activities, such as drawing a weapon, using a baton, handcuffing, and using a taser. This difference is not explained by factors other than race. (The study authors controlled for other causes, and race emerged as an independent variable predicting use of force.)  This is where police education is likely to be most effective, because it does seem to be a factor of police behavior.

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Jun 15 2020

COVID-19 Lockdown and the Flu

There is pretty clear evidence now that the lockdown worked in “flattening the curve” and reducing cases, hospitalizations, and deaths from COVID-19.  By one estimate the lockdown has already prevented about 60 million cases in the US alone, and about 250,000 additional deaths, perhaps more. This doesn’t even take into consideration what would have happened if the pandemic was allowed to overwhelm hospital systems around the country. In the Northeast, which was hit early and hard, hospital systems were overwhelmed in that they had to reconfigure their resources, and compromise on protocols in order to meet the demand. In some NY hospitals they had two patients on one ventilator. Imagine this, but far worse, and more widespread. How many deaths not directly related to COVID-19 would have resulted from this strain on the system?

So I think we can take fair comfort in the fact that the lockdown, as painful as it is, has at least worked as intended. Many people have raised the question – did the lockdown work also on the flu? If so, why don’t we do some version of the lockdown during the height of flu season? We now have data on the effect of the lockdown on this year’s flu season in the northern hemisphere – it stopped the flu season about 5 weeks earlier than is typical.  It’s possible some of this decrease in numbers is due to fewer people seeking treatment, but it’s likely that it is mostly due to reduced spreading of the flu virus.

This year in the US the flu season was toward the higher end in terms of cases and deaths – not out of the range of typical flu seasons, but at the bad end of the spectrum. In the US there were between 39 and 56 million cases of flu this year, with 24-62 thousand deaths. The upper limit of flu season deaths is around 65 thousand. The reason for the wide estimate range is because most people don’t get tested in order to confirm that their flu-like illness is indeed the flu. So confirmed cases are a small percentage of total cases, which are estimated by clinical presentation. Globally the estimated number of flu deaths each year is 290,000–650,000.  Right now the global number of deaths attributed to COVID-19 is 436,000, but the number of new cases is still on the upswing.

Before you fall prey to the “COVID-19 is just a bad flu season” fallacy, keep in mind that the pandemic is not over yet. And, as stated, this is with lockdown. But, what does this say about how we handle typical flu seasons, and how we will likely handle COVID-19 in the future? Here are some thoughts.

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Jun 12 2020

China and the Pangolin Trade

Pangolin’s are adorable and weird animals. They are mammals, with eight (although some references say seven) species in their own order, the Pholidota (all eight species are also in the same family and genus). They have scales, no teeth, and a long tongue, and are native to Africa and Asia. They are also endangered for a very specific reason – their scales are valued as medicine in Traditional Chinese Medicine. They are endangered because of culturally and politically sanctioned pseudoscience.

This is why it has come as welcome news that China has finally removed pangolin scales from the list of official TCM treatments. They have also upgraded pangolins to the highest level of protection. I applaud this decision, which may be a “game changer” in terms of protecting pangolins, but I do have to point out that China is just mitigating a problem entirely of its own creation. It’s like announcing that you are going to stop beating your wife. Congratulations.

What remains to be seen is how strictly they are going to enforce their new protections. Striking pangolins from the list of official TCM products will not magically erase centuries of culture, or a very lucrative black market – just as banning ivory did not instantly disappear the ivory trade and save the elephant. Further, China needs to do the same thing for the entire list of TCM treatments based upon animals parts. No tiger bones, bear bile, or rhino horn.

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Jun 11 2020

What Is Twistronics

It’s hard to keep up with all the latest science and technology, even for an enthusiast. Entire new fields are emerging, and it can be challenging for the non-expert to wrap their head around all the new concepts. Here is my attempt to quickly tackle a relatively new idea in physics – twistronics.

The term refers to tuning the properties of 2-dimensional materials by stacking them and rotating the layers with respect to each other. This is a lot harder than it sounds – graphene (2d carbon in a hexagonal configuration, like chicken wire) for example likes to align itself and will resist such twisting. Further, it is difficult to make pure 2d sheets without errors or contamination. But some theoretical physicists were predicting that interesting things might happen at certain “magic” angles of rotation, such a 1.1 degrees. It was then left to experimental physicists to make it happen.

This has all been happening very quickly, over the last few years. It was in 2018, in fact, that physicist Pablo Jarillo-Herrero published the first study showing the properties of graphene “devices” with a twist angle of 1.1 degrees. What he found at this magic angle was something, he now reports, that he dared not predict or even hope for, one of the holy grails of material science – superconductivity.

A superconducting material is essentially one that allows for the flow of electrons without any resistance, and therefore no loss of energy as heat. Superconductivity would transform our electrified world and allow for the creation of much more powerful and efficient electronics. Physicists have created a number of superconducting materials, but at low temperature. The trick is to make so-called high-temperature superconducting material. This first became a popular sensation in the 1980s, with the discovery of superconducting ceramics. At the time, if you believed they hype, it seemed like a matter of just years before we would have room-temperature superconductors, with devices sitting on every desktop. Reality proved much more difficult.

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Jun 09 2020

Perhaps More Than Ever – Truth Matters

The following quote from a recent address to graduating student resonated with me:

“What’s become clear is that social media can also be a tool to spread conflict, divisions, and falsehoods, to bully people and promote hate,” he said. “Too often, it shuts us off from each other instead of bringing us together, partly because it gives us the ability to select our own realities, independent of facts or science or logic or common sense. We start reading only news and opinions that reinforce our own biases. We start cancelling everything else out. We let opinion masquerade as fact, and we treat even the wildest conspiracy theories as worthy of consideration.”

The speaker advises students to, “Use all that critical thinking you’ve developed from your education to help promote the truth.” I agree, although honestly I think students need to learn much more critical thinking than is typically the case. These words could have been spoken by any skeptic or science communicator, and is a core message of the skeptical movement. We need scientific literacy, deep understanding of critical thinking and how to apply it every day, and media literacy. But these words were spoken recently by former president Barack Obama. Don’t leg your political opinion of him, if they are negative, color your perception of these words. Let them speak for themselves.

That is actually the point I want to make in this post. Humans are tribal by nature. We now know from years of psychological study that we tend to plant our flag with one group, one ideology, one narrative – and then defend it at all costs. The more we identify with a position, or see it as a marker of our group, and the more we do, the greater our motivated reasoning. For things we don’t care about, or do not identify with, we tend to revert to a fairly rational approach – listening to new evidence and incorporating into our view. So we have the capacity to be rational, when our identity does not get in the way.

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Jun 08 2020

The Surgisphere Fiasco

The safety and efficacy of hydroxychloroquine for the treatment of COVID-19 has quickly become an important medical question in managing this pandemic, although not by far the most important. There are many drugs under consideration, and some with promising early results. But hydroxychloroquine has garnered the majority of attention for purely political reasons. I most recently wrote about the scientific evidence for hydroxychloroquine on May 18th, referring to four studies all showing no benefit. Since then there have been more studies, including this one in NEJM showing no benefit from hydroxychloroquine in terms of preventing the contraction of COVID-19. Systematic reviews, which are being done in an ongoing manner, also conclude no benefit from this drug.

But at the end of my May 18th blog post, on May 22nd, I added a brief addendum because another study had just come out I thought was worth noting – a multinational study which compiled evidence from 120 different hospitals involving over 90,000 patients. This study found no benefit but significantly an increased risk of heart complications and death from hydroxychloroquine. If you follow this link now you will see a giant “retracted” posted over the study. The Lancet reports:

But in an  last week, a group of scientists raised “both methodological and data integrity concerns” about it.

These included a lack of information about the countries and hospitals that contributed to the data provided by Chicago-based healthcare data analytics firm Surgisphere.

One other hydroxychloroquine study used data from Surgisphere, this one published in the NEJM, and has also since been retracted. So what happened and what does all this mean?

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Jun 04 2020

fMRI Researcher Questions fMRI Research

This is an important and sobering study, that I fear will not get a lot of press attention – especially in the context of current events. It is a bit wonky, but this is exactly the level of knowledge one needs in order to be able to have any chance of consuming and putting into context scientific research.

I have discussed fMRI previously – it stands for functional magnetic resonance imaging. It uses MRI technology to image blood flow to different parts of the brain, and from that infer brain activity. It is used more in research than clinically, but it does have some clinical application – if, for example, we want to see how active a lesion in the brain is. In research it is used to help map the brain, to image how different parts of the brain network and function together. It is also used to see which part of the brain lights up when subjects engage in specific tasks. It is this last application of fMRI that was studied.

Professor Ahmad Hariri from Duke University just published a reanalysis of the last 15 years of his own research, calling into question its validity. Any time someone points out that an entire field of research might have some fatal problems, it is reason for concern. But I do have to point out the obvious silver lining here – this is the power of science, self-correction. This is a dramatic example, with a researcher questioning his own research, and not afraid to publish a study which might wipe out the last 15 years of his own research.

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Jun 02 2020

Journalism Without Skepticism

A recent interview published in Scientific American is a good case study in what can happen when you have journalism without skepticism.  By skepticism I mean a working knowledge of the discipline of scientific skepticism, which combines our current understanding of the philosophy of science, the nature of pseudoscience, critical thinking, mechanisms of self-deception, deliberate deception, and specific knowledge about individual pseudoscientific and paranormal topics.

The interview was conducted by John Horgan, who I have trashed in the past for criticizing skepticism while demonstrating an almost complete ignorance of it. The subject of the interview was Leslie Kean, a journalist who has written a book on UFOs and another on life after death. Doing a deep dive into these two issues is beyond this one article, and they have already been covered at length here and elsewhere. I want to focus on what the interview itself reveals.

Kean appears to take a solid journalistic approach to these issues, but there is a massive hole in her approach. She does not seem to be aware that there is already a thorough investigation into these questions, showing convincingly in my opinion that they are not genuine. She ignores it because she thinks she already understands it, when she doesn’t – so she is missing the skeptical take on these issues. She is dismissive of skeptics as deniers and as closed-minded. She then goes on to make rookie mistakes, that any well-informed skeptic could have pointed out to her. The result is a repetition of long debunked fallacious arguments, but with a patina of serious journalism.

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Jun 01 2020

Junk Science in the Courtroom

In the last 20 years I have been called to jury duty several times. Every time I was dismissed almost instantly, once I made it known that I am a professional skeptic. Apparently lawyers fear that kind of skepticism on their juries (at least one side always did). The same is true of many of my skeptical colleagues, so I am not an isolated case. Once my brother said during the process that he wrote an article on the fallibility of human memory and eyewitness testimony. His but barely hit the seat when he was dismissed.

It is unclear how best to interpret these anecdotes, but what is clear is that justice requires facts and needs to align optimally with reality. Falsehoods and pseudoscience do not generally lead to justice. It is for this reason that courtrooms have elaborate rules of evidence, and generally they work well. Even in our adversarial system, you need to use generally valid arguments, you need to back up your statements with evidence, and there are rules of admissibility. Each side provides a check on the other, as a neutral arbiter presides over the process. It is imperfect (because imperfect people are involved) but at least it has a process.

One area where this process has historically had significant problems, however, is in forensic science, and the admissibility of science itself. The main problem, as I see it, is that it is based largely on authority, in both a good and bad way. Each side is allowed to find their own experts, and they can cherry pick experts whose opinion aligns with their needs. Often a non-expert jury is then tasked with sorting it out. There are standards for which expert testimony is admissible, and this has been a controversy unto itself. Here is a good summary:

Prior to 1993, the Frye standard for admitting expert testimony was the prevailing standard for guiding federal and state courts in their consideration as to whether scientific expert testimony should be admitted at trial. Frye v. United States[1]. The Frye standard requires that the proponent of the evidence establish the general acceptance of the underlying scientific principle and the testing procedures. Notably, Frye only applies to new or novel scientific evidence. However, in 1993, following a revision to the Federal Evidence Code by Congress, the Supreme Court of the United States annunciated the new standard in Daubert v. Merrell Dow Pharmaceuticals, Inc.[2] The Daubert inquiry was meant to be flexible and focused on scientific principles and methodology, not conclusions. The Daubert opinion emphasized that the Federal Rules of Evidence governed admissibility and suggested a series of factors a court could consider, but did not establish a test per se. Under Daubert, the admissibility of expert evidence rests squarely within the discretion of the trial court judge. In contrast to FryeDaubert applies to all expert witness testimony.

This article is about the fact that Florida has reverted to the Frye standard recently. This highlights the fact that legal precedent is largely how this is sorted out, and may differ for every state and at the federal level.

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