Scott analyzes whether whole-body screening MRIs are worth it by doing a detailed cost-benefit calculation, finding they cost about $108,000 per quality-adjusted life-year saved (right around the threshold of cost-effectiveness), and argues that while rich people immune to anxiety might benefit, most people claiming to be rational about medical decisions probably aren't. Longer summary

Scott performs a detailed cost-benefit analysis of whole-body screening MRIs in response to controversy over medical experts recommending against them. Using rough order-of-magnitude estimates, he calculates that screening 1,000 people saves about 32 quality-adjusted life-years (QALYs) at a cost of $2.7 million plus time and anxiety costs, working out to about $108,000 per QALY saved—right at the threshold of cost-effectiveness. He explores whether rich people who don't care about money should get screened, finding a plausible case but with many caveats about unknown factors that could swing the calculation either way. He then applies this analysis to Midjourney's proposed ultrasound scanner, finding it's unlikely to be clearly better than MRI. The post ends with a warning that people who think they're rational enough to ignore false positives are often the same people making irrational medical decisions based on contrarian appeals. Shorter summary

Scott travels to Medjugorje, Bosnia to investigate reports of sun miracles, witnesses one himself with his wife, and develops a naturalistic explanation involving afterimages and atmospheric conditions that explains both the Medjugorje and Fatima phenomena. Longer summary

Scott Alexander investigates the sun miracle at Medjugorje, Bosnia, where thousands of pilgrims report seeing the sun spin and change colors. He travels there with his wife, interviews locals, and witnesses a small-scale miracle himself. After analyzing the experience and comparing it to the famous Fatima miracle, he proposes a naturalistic explanation involving afterimages, eye damage, and specific cloud conditions. The post explores eyewitness accounts, the history of Marian apparitions at Medjugorje, and the optical physics behind the phenomenon, ultimately concluding that while impressive, the miracle can be explained through unusual but natural atmospheric conditions combined with prolonged sun-gazing. Shorter summary

Scott demonstrates that US crime rates are at historic lows using multiple data sources, then debunks the theories that this is due to reporting bias or improved medical care, before briefly discussing possible explanations for the decline. Longer summary

Scott presents evidence that US crime rates, particularly murder rates, are at or near historic lows, then systematically debunks two common objections: that the decline is due to underreporting bias, and that it's an artifact of improved medical care saving would-be murder victims. He shows that multiple independent data sources (including victim surveys and consistently-reported crimes like car theft) confirm the decline, and that while medical care has improved, gun injuries have become more severe at roughly the same rate, canceling out the effect. The post concludes by listing various theories for why crime has declined and questioning why public perception doesn't match the data. Shorter summary

A detailed investigation of the Sun Miracle of Fatima in 1917, where 70,000 people witnessed the sun appear to spin, change colors, and fall to earth, analyzing witness testimonies, skeptical explanations, and similar phenomena at other Marian apparition sites. Longer summary

Scott conducts an extensive investigation into the 1917 Miracle of the Sun at Fatima, where tens of thousands witnessed what appeared to be the sun spinning, changing colors, and falling to earth. He examines approximately 60 primary testimonies, evaluates common skeptical explanations (optical phenomena, weather events, mass hallucination), and documents similar sun miracles at other Marian apparition sites worldwide. Scott then critiques Dalleur's theory about distant witnesses and shadow analysis, explores why more people don't see these phenomena normally, and proposes a tentative materialist explanation involving a rare optical illusion modulated by cloud cover and social priming. The post ends by suggesting research directions for those interested in further investigation. Shorter summary

A detailed review of a 1995 paper introducing the PDAPP mouse model for Alzheimer's disease, examining how its limitations were overlooked and shaped decades of potentially misguided Alzheimer's research. Longer summary

The post reviews a landmark 1995 paper introducing the PDAPP mouse model for Alzheimer's disease, analyzing how its technical achievements and limitations shaped three decades of Alzheimer's research. The author examines the paper's methodology, results, and claims, showing how the model's flaws - including extreme protein overexpression and lack of key disease features - were overlooked in favor of a compelling but incomplete amyloid cascade hypothesis, leading to years of failed drug development and missed opportunities to explore alternative approaches. Shorter summary

Scott explores the 'missing heritability' problem in genetics, where twin studies show traits like IQ and educational attainment are highly heritable but newer genomic methods find much lower heritability, analyzing various potential explanations for this discrepancy. Longer summary

The post examines the 'missing heritability' problem in genetics, where twin studies consistently show behavioral traits like IQ and educational attainment are substantially heritable (around 40-60%), while newer genomic methods find much lower heritability (around 15-20%). Scott reviews the history of behavioral genetics research, explains various study methodologies and their potential biases, and analyzes different hypotheses for this discrepancy. He examines whether twin studies might be flawed, whether newer methods might be missing important genetic effects, and whether educational attainment might be an unusually problematic trait to study. While acknowledging remaining mysteries, he tentatively concludes that twin studies are probably largely correct and that newer methods may be missing rare variants and genetic interactions. Shorter summary

The post argues against California's Proposition 36, claiming it will increase imprisonment without effectively reducing crime or drug use, and suggests alternative solutions. Longer summary

This post argues against California's Proposition 36, which aims to increase mandatory sentences for certain drug and theft crimes. The author contends that while Prop 36 will certainly imprison more people, it won't effectively combat crime. The post analyzes the proposition's impact on drug-related offenses and theft, using data to show that increased sentencing doesn't correlate with reduced drug use or crime rates. It also points out the lack of treatment resources required by the proposition and the potential negative impact on existing crime prevention programs. The author suggests that instead of longer sentences, California should focus on targeted interventions, increased police resources, and expanding treatment options for drug addiction. Shorter summary

Scott Alexander investigates why self-reported IQ scores in online surveys are implausibly high, identifying issues with conversion tools, reporting bias, and unreliable tests. Longer summary

Scott Alexander investigates why self-reported IQ scores in online surveys seem implausibly high. He analyzes data from two surveys (Less Wrong 2014 and Clearer Thinking 2023) and identifies three main issues: 1) A popular SAT to IQ conversion tool was inaccurate, inflating scores. 2) Only the smartest people tend to report their SAT scores, skewing the sample. 3) Self-reported IQ test scores are often inflated or based on unreliable tests. After accounting for these factors, he estimates the average IQ of the Clearer Thinking sample at 111 and the Less Wrong sample at 128, which he considers more plausible. Shorter summary

Scott Alexander proposes that political hyperpartisanship might be a form of trauma, comparing PTSD symptoms to behaviors observed in political extremists. Longer summary

Scott Alexander explores the idea that political extremism might be a form of trauma. He compares symptoms of PTSD to behaviors observed in politically hyperpartisan individuals, such as triggers, distorted cognitions, and hypervigilance. The post discusses how trapped priors in the brain might explain both cognitive and emotional aspects of political extremism. Scott also considers the implications of framing political partisanship as trauma, including potential risks of expanding the concept of trauma. Shorter summary

Scott Alexander summarizes and responds to various comments on his kidney donation post, covering a wide range of related topics and perspectives. Longer summary

Scott Alexander provides highlights from comments on his kidney donation post, covering various perspectives and topics. These include comments from other kidney donors and recipients, discussions on opt-out organ donation systems, debates on radiation risk from screening tests, issues with rejection during the donation process, polls about willingness to donate, and developments in artificial organ technology. Scott also responds to many comments, offering additional insights and reflections on the donation process and related ethical considerations. Shorter summary

Scott Alexander recounts his experience donating a kidney, from initial motivation to post-surgery recovery, while discussing the broader context of organ donation. Longer summary

Scott Alexander describes his journey to donate a kidney, including his motivations, the medical process, and the challenges he faced. He discusses the effectiveness of kidney donation compared to other forms of altruism, the stigma around mental health in the donation process, and the need for systemic changes to address the kidney shortage. Scott also reflects on the experience of the surgery and recovery, and encourages others to consider donation. Shorter summary

A critical review of 'Why Nations Fail' that examines the authors' academic work and methodology, while questioning the book's quality and practical implications. Longer summary

This review critiques 'Why Nations Fail' by Acemoglu and Robinson (AR), arguing that while the book itself is not very good, AR's academic papers present a more compelling case for their thesis that political institutions are the main determinant of economic growth. The reviewer explains AR's methodology using instrumental variables, discusses their evidence and criticisms, and ultimately concludes that even if AR are correct, their extremely long-run focus may not be very useful for practical policymaking or development efforts. Shorter summary

Scott Alexander investigates the claim that children learn languages faster than adults, finding it partially true but more nuanced than commonly believed. Longer summary

Scott Alexander examines the claim that children learn languages faster than adults, finding it to be partially true but more complex than commonly believed. He explores various aspects of language acquisition, including critical periods for first language learning, age effects on second language learning, and differences in learning rates between children and adults. The post concludes that while children seem to pick up second languages faster than adults, this advantage is not as clear-cut as often thought, and factors like exposure, motivation, and declining learning rates with age play significant roles. Shorter summary

Scott Alexander examines hypergamy in modern marriages, finding educational hypergamy has reversed while income hypergamy persists, with strong class homogamy for both genders. Longer summary

Scott Alexander examines the concept of hypergamy, particularly focusing on educational and income differences in heterosexual marriages. He finds that while educational hypergamy (women marrying more educated men) has reversed due to women's increasing educational attainment, income hypergamy (women marrying higher-earning men) persists. The post explores various studies on class, income, and educational matching in marriages, discusses the role of physical attractiveness, and touches on hypergamy in same-sex relationships. Scott concludes that class homogamy is strong for both genders, with looks playing a smaller role than often assumed in mate selection. Shorter summary

Scott Alexander explores the ethics of eugenics and population control through fictional debates, comparing historical figures and policies. Longer summary

Scott Alexander discusses the ethics of eugenics and population control through a dialogue between fictional characters. The post starts with a debate on whether eugenics can be ethical if implemented voluntarily, then compares the historical impacts of eugenics advocate Francis Galton and population control advocate Paul Ehrlich. It explores how Ehrlich's ideas led to forced sterilizations in India yet he remains respected, while Galton is vilified. The dialogue then debates whether this discrepancy is justified and how to evaluate ideas that led to harmful outcomes. The post ends with a discussion on the role of government in implementing controversial policies for perceived greater goods. Shorter summary

Scott Alexander responds to criticism of his post on housing density and prices, refining but largely maintaining his argument that increased density can raise local prices. Longer summary

Scott Alexander responds to comments on his previous post about housing density and prices. He addresses several key points, including whether density causes desirability, the role of jobs and amenities in city desirability, Chinese ghost cities, comparisons to Tokyo, accusations of misunderstanding economics, and opinions from notable experts. Scott refines some of his views but maintains his core argument that increasing density within a city can increase housing prices by making the city more desirable, while acknowledging this effect may be limited or outweighed by other factors in many cases. Shorter summary

Scott Alexander shares a diverse collection of interesting links and news items for April 2023, covering topics from unusual stories and scientific research to AI developments and global trends. Longer summary

Scott Alexander presents a collection of interesting links and news items for April 2023. The post covers a wide range of topics, including unusual stories, scientific research, political developments, AI progress and concerns, cultural phenomena, and more. Notable items include a real-life 'Cocaine Bear' story, an adversarial collaboration on income and happiness, concerns about AI development, and updates on global trends like birth rates in Africa. The post also includes several short fiction recommendations and humorous AI-related anecdotes. Shorter summary

Scott reviews a book on culture-bound syndromes, expanding the discussion to how all mental illnesses are influenced by culture to varying degrees. Longer summary

Scott Alexander reviews 'The Geography of Madness' by Frank Bures, which explores culture-bound syndromes like koro (belief in penis theft by witches). The book traces the history and spread of these syndromes across cultures. Scott expands on the idea, discussing how all mental illnesses exist on a spectrum of biological vs. cultural influence. He argues that even conditions considered 'real' in Western psychiatry, like anorexia or PTSD, have significant cultural components. The review touches on complex issues around gender dysphoria and cultural beliefs, concluding that there is no truly 'neutral' culture free from influence on mental health presentations. Shorter summary

Scott Alexander argues that even seemingly extreme media misinformation usually involves misleading presentation of true facts rather than outright fabrication, examining several reader-provided counterexamples. Longer summary

Scott Alexander responds to criticisms of his previous post about media rarely lying by examining several examples readers provided. He argues that even in extreme cases like Alex Jones' Sandy Hook conspiracy theories or claims about election fraud, media sources are typically highlighting true but misleading facts rather than outright fabricating information. Scott contends this matters because it means efforts to censor 'misinformation' will always require subjective judgment calls rather than being a straightforward process of removing falsehoods. He suggests people want to believe bad actors are doing something fundamentally different than good faith reasoning, but in reality most are just reasoning poorly under uncertainty. Shorter summary

Scott Alexander analyzes the potential role of psychopharmacology in the FTX crash, discussing medications used by SBF and others, and their possible effects on decision-making. Longer summary

Scott Alexander discusses the psychopharmacology aspects of the FTX crash, focusing on the medications Sam Bankman-Fried (SBF) and other FTX employees may have been taking. He examines claims about SBF's use of Emsam (selegiline), modafinil, and other stimulants, explaining their effects and potential risks. Scott also critiques the actions of FTX's company psychiatrist and discusses the broader implications of stimulant use in high-pressure work environments. The post ends with Scott's personal anecdote about testifying as an expert witness. Shorter summary

Scott examines two types of happiness - one affected by predictability and one that persists - through various examples and neuroscientific concepts. Longer summary

Scott Alexander explores the concept of happiness and reward in relation to neuroscience and prediction error. He discusses how there seem to be two types of happiness: one that is cancelled out by predictability (like the hedonic treadmill) and another that persists even when expected. The post delves into various examples including grief, romantic relationships, and drug tolerance to illustrate this pattern. Scott also touches on AI concepts and how they might relate to human reward systems. He concludes by suggesting that while unpredicted rewards can't be consistently obtained, predicted rewards can still be enjoyable. Shorter summary

Scott Alexander examines why skills plateau, proposing decay and interference hypotheses to explain the phenomenon across various fields. Longer summary

Scott Alexander explores why skills plateau despite continued practice, focusing on creative artists, doctors, and formal education. He presents two main hypotheses: the decay hypothesis, where knowledge is forgotten if not regularly reviewed, and the interference hypothesis, where similar information blends together, making it difficult to learn new things in the same domain. The post discusses how these hypotheses explain various learning phenomena, including the ability to learn multiple unrelated skills simultaneously. Scott also considers edge cases and potential applications of these theories, such as mnemonic devices and language learning strategies. Shorter summary

Scott Alexander defends his analysis of the 2020 US homicide spike against various counterarguments, maintaining that it was primarily caused by changes in policing following protests. Longer summary

Scott Alexander responds to comments on his previous post about the 2020 homicide spike in the US. He addresses several counterarguments and alternative explanations, including the role of increased gun sales, racial differences in homicide rates, the exact timing of the spike, changes in policing behavior, media coverage, academic literature on the topic, and potential effects of warm weather. Scott largely maintains his original position that the spike was primarily caused by changes in policing following protests, rather than other factors like the pandemic or increased gun ownership. Shorter summary

Scott Alexander presents evidence that the 2020 US homicide spike was caused by Black Lives Matter protests rather than the COVID-19 pandemic. Longer summary

Scott Alexander argues that the 2020 homicide spike in the US was primarily caused by the Black Lives Matter protests rather than the COVID-19 pandemic. He presents evidence on timing, demographics, police pullback, and comparisons with other countries and previous protests to support his claim. The post criticizes media coverage for attributing the spike to complex factors or the pandemic, suggesting a bias in reporting. Shorter summary

Scott Alexander critiques the claim that 'America has two X-wing parties' as meaningless or misleading, urging for more precise political comparisons. Longer summary

Scott Alexander criticizes the common political trope that 'America has two left-wing parties' or 'America has two right-wing parties'. He argues that this claim is meaningless when taken as an absolute statement, as there's no objective center in politics. When considered as a relative claim, it's either false (relative to US voters) or inconsistent (relative to other countries). He suggests that people making such claims are often comparing to specific reference points like US history or OECD countries, and should explicitly state their comparisons instead of making broad, ambiguous statements. Shorter summary