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 analyzes research on whether longer prison sentences reduce crime, examining studies on deterrence, incapacitation, and aftereffects, to conclude that while prison does decrease crime through incapacitation, it's less cost-effective than other methods like policing. Longer summary

This post examines the relationship between prison sentences and crime reduction through three mechanisms: deterrence (scaring potential criminals), incapacitation (preventing prisoners from committing crimes), and aftereffects (post-release behavior changes). Through analysis of multiple studies and reviews, Scott finds that deterrence effects are minimal, incapacitation has strong positive effects (preventing about 7 crimes per prisoner-year), and aftereffects range from slightly beneficial to harmful depending on circumstances. He concludes that while prison does reduce crime, with a 10% increase in incarceration reducing crime by about 3%, it's less cost-effective than alternatives like increased policing. The post ends by examining practical challenges in the justice system that prevent effective handling of repeat offenders. Shorter summary

Scott examines data on COVID-19 lockdown effectiveness, finding they likely reduced transmission but at significant costs, with targeted measures being most effective. Longer summary

Scott analyzes the effectiveness of COVID-19 lockdowns, examining data from Sweden, US states, and Europe. He finds that lockdowns likely reduced transmission rates, with targeted measures like school closures being more effective than stay-at-home orders. The analysis suggests lockdowns saved lives but at significant economic and emotional costs, with the cost-effectiveness varying between countries and time periods. Scott concludes that fast, well-targeted lockdowns may have been optimal, but emphasizes the high uncertainty in these estimates. Shorter summary

The post compares space colonization and terrestrial lifeboats as X-risk mitigation strategies, concluding that space colonies may offer better long-term survival guarantees despite higher costs. Longer summary

This post discusses the merits of colonizing space versus creating terrestrial lifeboats as strategies to mitigate existential risks (X-risks) to humanity. The authors, Nick D and Rob S, compare the costs, feasibility, and effectiveness of off-world colonies and Earth-based closed systems. They explore the challenges and benefits of each approach, including isolation from global catastrophes, technological requirements, and potential for research and economic opportunities. The collaboration concludes that while terrestrial lifeboats are more cost-effective and easier to implement, space colonies might offer better long-term guarantees for human survival due to the difficulty of abandoning them. Shorter summary

Scott Alexander examines a study showing positive effects of early intervention on at-risk children, but questions its policy implications due to high costs. Longer summary

Scott Alexander discusses a study on early intervention programs for at-risk children, which showed positive effects on various outcomes at age 25. The study, a randomized controlled trial, found that intensive interventions costing $60,000 per child reduced the odds of developing psychiatric disorders, substance abuse problems, and engaging in criminal behavior. While the results are scientifically interesting, Scott points out some limitations and questions the cost-effectiveness from a policy perspective. He notes that the intervention didn't affect all outcomes equally and that the high cost might not justify the benefits when compared to existing educational spending. Shorter summary

Scott Alexander examines evidence on marijuana legalization's effects on usage, health, and drug war costs, finding uncertainties too large for firm conclusions but suggesting traffic accidents may be the key factor. Longer summary

Scott Alexander examines the evidence around marijuana legalization, looking at its effects on usage rates, health impacts, and costs of the drug war. He finds that decriminalization and medical marijuana don't seem to increase youth usage much, but full legalization might increase adult use by 25-50%. Health effects are unclear but may include IQ declines and slightly increased psychosis risk. The costs of the drug war are significant in terms of arrests and spending, but relatively few people are in prison solely for marijuana. Scott attempts a utilitarian analysis comparing costs and benefits of legalization, but finds the uncertainties too large to draw firm conclusions. He suggests the most important factor may be how legalization affects traffic accidents. Shorter summary