Scott Alexander responds to critiques of his 2021 ivermectin analysis, acknowledging some errors but maintaining his conclusion that ivermectin likely doesn't work for COVID-19. Longer summary

Scott Alexander responds to Alexandros Marinos' critique of his 2021 post on ivermectin studies, addressing points about individual studies, meta-analysis methods, publication bias, and new evidence since 2021. He acknowledges some mistakes in his original analysis but maintains his overall conclusion that ivermectin is likely ineffective for COVID-19. Shorter summary

Scott Alexander analyzes ivermectin studies for COVID-19, finding most positive results likely due to methodological flaws, fraud, or confounding by parasitic infections. Longer summary

Scott Alexander provides an in-depth analysis of ivermectin studies for COVID-19 treatment, examining methodological issues, potential fraud, and confounding factors. He concludes that ivermectin likely doesn't significantly reduce COVID mortality except potentially in areas with high parasitic worm infections. The post explores broader issues around scientific credibility, fraud detection, and public trust in science. Shorter summary

Scott reviews 'Arabian Nights', exploring its themes, fantastical elements, and proposing a meta-interpretation of Scheherazade's storytelling strategy. Longer summary

Scott reviews 'One Thousand And One Nights', also known as 'Arabian Nights'. He describes the framing story of Scheherazade telling stories to King Shahryar to save her life, and explores the themes and recurring elements in the tales. Scott notes the prevalence of adultery, particularly involving black men, and describes the idealized Middle Eastern setting. He discusses various elements like genies, magic, diversity, religion, and fantastical creatures. The review then speculates on Scheherazade's storytelling strategy, suggesting she might be teaching the king to build better mental categories. Finally, Scott proposes a meta-interpretation where Scheherazade uses nested storytelling to exploit indexical uncertainty, potentially influencing her own reality. Shorter summary

Scott Alexander critically examines studies on preschool effects, finding mixed and inconsistent evidence for long-term benefits. Longer summary

Scott Alexander reviews multiple studies on the long-term effects of preschool programs like Head Start. While early studies showed fade-out of test score gains, some found lasting benefits in adult outcomes. However, Scott finds inconsistencies between studies in which subgroups benefit and on which outcomes. He also notes concerns about potential p-hacking and researcher degrees of freedom. Ultimately, Scott concludes that the evidence is mixed - it permits believing preschool has small positive effects, but does not force that conclusion. He estimates 60% odds preschool helps in ways suggested by the studies, 40% odds it's useless. Shorter summary

Scott Alexander revisits his stance on SSRIs, discussing new meta-analyses, broader trends in psychiatric medication efficacy, and potential explanations for the discrepancy between statistical and clinical observations. Longer summary

Scott Alexander updates his views on SSRIs, addressing four key points: 1) A meta-analysis confirming the effect size of antidepressants is about 0.3. 2) The low effect size of SSRIs is part of a broader trend of low effect sizes in psychiatric medications. 3) A hypothesis to reconcile the small statistical effect with strong clinical observations, suggesting SSRIs might work very well for a subset of patients. 4) The possibility that SSRIs' efficacy for anxiety might contribute to their perceived effectiveness for depression. Shorter summary

Scott Alexander critically examines a major meta-analysis on antidepressant efficacy, noting potential biases and comparing its surprising drug rankings to his own previous analysis. Longer summary

This post reviews a major meta-analysis by Cipriani et al on the efficacy of antidepressants. The study claims to definitively show antidepressants work, but Scott notes it doesn't actually refute previous critiques about their effectiveness. He examines potential biases and methodological issues in the study, particularly around industry funding of trials. Scott also discusses the study's ranking of different antidepressants, noting some matches with conventional wisdom but also some surprising results. He compares these rankings to his own previous analysis, finding major discrepancies, and concludes by urging some caution in interpreting the study's results despite its impressive scope. Shorter summary

Scott Alexander critiques Adam Grant's article on gender differences in tech, arguing Grant misrepresents evidence and ignores key factors like innate interest differences between men and women. Longer summary

Scott Alexander critiques Adam Grant's article on gender differences, arguing that Grant misrepresents scientific evidence and ignores important factors like interest differences between men and women. Scott presents alternative explanations for gender imbalances in tech and other fields, emphasizing innate differences in interests rather than discrimination. He expresses concern about the hostile climate developing in tech around these issues. Shorter summary

Scott Alexander examines a failed replication of a study claiming analytical thinking promotes religious disbelief, and discusses the broader implications for understanding the relationship between thinking styles and religious belief. Longer summary

Scott Alexander reviews a study by Gervais and Norenzayan (G&N) that claimed analytical thinking promotes religious disbelief, and its subsequent failed replication attempts. The original study consisted of five experiments, including priming participants with images or word tasks before assessing their religious beliefs. The Reproducibility Project's replication of two of these experiments failed to find the same effects. Scott discusses the implications of this failure, noting that even studies that seem well-designed can fail to replicate. He then examines a meta-analysis by Pennycook et al. that found a small but consistent correlation between analytical thinking and irreligiosity across multiple studies. Scott concludes by summarizing key takeaways about the relationship between analytical thinking, IQ, and religious belief, as well as lessons about the replicability of psychological studies. Shorter summary

The post explores the complex relationship between smoking and schizophrenia, critiquing conflicting studies and cautioning against hasty conclusions about nicotine's effects on schizophrenia risk. Longer summary

This post examines the relationship between smoking and schizophrenia. It starts by noting the high prevalence of smoking among schizophrenics and discusses various theories for this, including the self-medication hypothesis. The author then analyzes two conflicting studies on whether smoking causes or prevents schizophrenia. One study suggests smoking increases risk, while another, which controls for confounders, indicates smoking may decrease risk. The post criticizes how the first study, despite being newer, ignores the contradictory findings of the second study. The author expresses frustration with this scientific approach and cautions against pushing people at risk of schizophrenia away from nicotine without stronger evidence. The post ends by noting that smoking definitely decreases Parkinson's Disease risk and reiterating that tobacco smoking is still harmful overall. Shorter summary

Scott Alexander offers follow-up insights on his guns and states analysis, addressing cultural factors, rape correlations, replication issues, and the complexity of gun control debates. Longer summary

Scott Alexander provides follow-up thoughts on his previous post about guns and states. He discusses the interaction between cultural factors and gun ownership, explores correlations with rape rates, addresses replication issues, and critiques the gun control debate. He also mentions a meta-analysis by Gary Kleck that shows mixed results in guns-homicide correlation studies, emphasizing the importance of considering multiple studies rather than relying on a single one. Shorter summary

Scott Alexander analyzes two conflicting studies on gender bias in STEM hiring, exploring reasons for their contradictory results and the challenges in reaching a definitive conclusion. Longer summary

Scott Alexander discusses two contradictory studies on gender bias in STEM hiring, one showing bias against women and another showing bias in favor of women. He explores possible reasons for the discrepancy, including differences in methodology and potential experimenter bias. The post highlights the difficulty in reaching a definitive conclusion on this issue despite its importance and the resources dedicated to studying it. Scott suggests that the conflicting results might be due to subtle experimenter effects and proposes a joint study by both teams as a potential solution. Shorter summary

Scott Alexander cautions against basing opinions on limited research, using examples from medicine and economics to show how cherry-picking studies can lead to opposing conclusions. Longer summary

Scott Alexander warns against relying on a single study or a limited selection of studies to form opinions on complex issues. He illustrates this with examples from medical research and the minimum wage debate, showing how cherry-picking studies can lead to opposing conclusions. The post emphasizes the importance of considering the full body of evidence, including meta-analyses and expert opinions, while also being aware of potential biases in research and reporting. Scott concludes by advocating for skepticism and thorough investigation when evaluating claims backed by scientific studies. Shorter summary

The author revisits their belief in genetic determinism, presenting evidence that environmental factors, especially in divorce, have significant non-genetic effects on children's outcomes. Longer summary

The post discusses the author's initial belief in the genetic determinism thesis from 'The Nurture Assumption', which argues that parenting has little effect on children's outcomes compared to genetics. The author then presents evidence from divorce studies that challenge this view, showing that environmental factors, particularly family conflict, do have significant effects on children. The post reviews several studies that disentangle genetic and environmental effects of divorce, concluding that there are indeed non-genetic negative impacts of divorce on children. The author acknowledges being wrong about shared environment effects being negligible and suggests that short-term environmental impacts can have long-lasting consequences. Shorter summary

Scott Alexander critiques a meta-analysis supporting psychic phenomena to illustrate flaws in scientific methodology and meta-analysis. Longer summary

Scott Alexander examines a meta-analysis by Daryl Bem that claims to provide strong evidence for psychic phenomena (psi). While Bem's analysis follows many best practices for scientific rigor, Alexander argues it likely suffers from experimenter effects and other biases that can produce false positive results. He uses this to illustrate broader issues with the scientific method and meta-analysis, concluding that even seemingly rigorous studies and meta-analyses can produce incorrect conclusions. This challenges the idea that scientific consensus and meta-analysis are the highest forms of evidence. Shorter summary

Scott Alexander critiques mass-produced medical recommendations, showing how they can oversimplify or misrepresent scientific evidence using vitamin D and niacin as examples. Longer summary

Scott Alexander critiques mass-produced medical recommendations, focusing on vitamin D and niacin supplements. He argues that popular sources like information graphics and websites often oversimplify or misrepresent the scientific evidence. Using vitamin D as an example, he shows how counting only positive studies can lead to misleading conclusions, as many larger studies and meta-analyses have found no benefit for cancer prevention or general health. He then discusses niacin, once thought beneficial but later found to be potentially harmful. Scott emphasizes the importance of considering all available evidence and being cautious about simplified recommendations. Shorter summary

Scott Alexander examines the claim that '90% of medical research is false', arguing it's an exaggeration while acknowledging real issues in the field. Longer summary

Scott Alexander critiques the popular claim that '90% of medical research is false', which is often attributed to John Ioannidis. He argues that this statement, while pointing to important issues, creates more panic than warranted. Scott analyzes Ioannidis' work, showing that the 90% figure is likely misinterpreted from various sources. He explains that the accuracy of medical research varies greatly depending on the type of study, with large randomized trials and meta-analyses being much more reliable. Scott also discusses how multiple studies on the same topic can greatly increase confidence in results, and how doctors' beliefs are typically based on substantial evidence rather than single studies. He concludes by acknowledging the problems in medical research while cautioning against overly cynical interpretations. Shorter summary