A replication of a 2023 neuroscience study on brain entrainment and learning found that the original effect likely doesn't exist, revealing how the study obscured key issues through statistical averaging and highlighting how AI tools are democratizing scientific scrutiny. Longer summary

Sasha Putilin received an ACX grant to replicate a 2023 study claiming that flickering lights synchronized to individual brain rhythms could boost learning speed threefold. The $32,000 replication with 12 participants (versus 80 in the original) found no such effect. Upon examining the original data more closely, Putilin discovered the apparent effect was driven entirely by a few participants with large negative learning rates (getting worse over time) who happened to all be in one experimental group. The original study had obscured this pattern by presenting averaged data rather than individual results. Putilin argues this exemplifies 'cargo-cult statistics' where researchers mechanically apply statistical rituals without critically examining underlying data. The post concludes by suggesting AI tools are democratizing meta-science, enabling anyone to audit published research that previously required expert-level effort. 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 data-driven analysis of the ACX/SSC comment section quality over time reveals historical peaks and valleys, with recent signs of improvement after previous declines in 2016 and 2021. Longer summary

This review analyzes the quality of the Astral Codex Ten (ACX) comment section over time, comparing it to its predecessor Slate Star Codex (SSC). Through detailed data analysis of 1.8M comments across 2,460 posts, the author identifies two major changes in comment quality - one in 2016 and another during the 2021 transition to ACX. The analysis looks at four key metrics: depth of engagement, freedom of intellectual engagement, politeness, and complexity of thought. While the data shows a decline after these turning points, recent trends suggest the comment section may be recovering. The author explores several hypotheses for the 2016 decline, including changes in post frequency and the impact of Trump's rise on discussion norms. Shorter summary

Scott presents evidence that COVID-19 did kill approximately 1.2 million Americans, addressing skeptics by analyzing excess death data and addressing common counterarguments. Longer summary

In response to skeptics questioning the official COVID-19 death toll, Scott Alexander presents evidence supporting the 1.2 million deaths figure. He shows excess mortality data from multiple sources indicating 500,000-700,000 extra deaths in both 2020 and 2021, closely matching reported COVID deaths. He addresses various counter-arguments, including the 'died with vs of COVID' distinction, the role of treatments like ventilators, and the common experience of not personally knowing COVID victims. The post demonstrates how the data supports COVID being the primary cause, and explains why personal experiences might not reflect the true scale of the pandemic. Shorter summary

Scott analyzes ACX survey data on Internet addiction, exploring correlations between usage patterns, life satisfaction, and parental restrictions, while acknowledging the difficulty of establishing causation in the findings. Longer summary

Scott analyzes data from the 2023 ACX survey regarding Internet addiction, focusing on self-reported addiction levels, screen time, life satisfaction, and parental restrictions. The survey included nearly 6,000 respondents and explored correlations between these factors. While results showed that Internet addicts were less happy and that childhood restrictions correlated with lower adult Internet use, the study couldn't establish causation due to possible genetic or cultural confounding factors. Scott also examined how current Internet users plan to restrict their own children's Internet use, finding interesting patterns between self-rated addiction and actual time spent online. 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 shares the results of the 2024 Astral Codex Ten survey, providing access to data and promising future analyses. Longer summary

Scott Alexander presents the results of the 2024 Astral Codex Ten survey, which had 5,981 participants. He provides links to the survey questions and results, and offers a downloadable dataset of responses from those who agreed to share their data publicly. Scott mentions that more detailed analyses will be published throughout the year, and invites readers to explore the data themselves. He also notes some measures taken to protect respondents' anonymity in the public dataset. Shorter summary

Scott Alexander responds to comments on polyamory, providing data and addressing concerns about relationship satisfaction, child-rearing, and abuse risks in poly relationships. Longer summary

Scott Alexander responds to comments on his previous posts about polyamory, addressing various arguments and providing data where possible. He discusses statistics on relationship satisfaction and child-rearing in poly vs. monogamous relationships, addresses concerns about abuse risks, and shares personal observations. The post touches on cultural perceptions of polyamory, its prevalence among different groups, and potential societal impacts. Scott also reflects on some new insights he gained from the discussion, particularly around child-rearing in poly relationships and abuse risks. Shorter summary

Scott Alexander tests a hypothesis about gender integration moderating political views using his survey data, finding no significant effect of sibling gender on political attitudes. Longer summary

Scott Alexander examines a claim about gender differences in political attitudes and tests a hypothesis using data from his 2022 survey. The post discusses a reported growing political gap between men and women, and a proposed explanation that increased gender integration might moderate political views. Scott tests this by comparing political attitudes of men and women with only brothers or only sisters. The results show no significant effect, suggesting that sibling gender doesn't influence political views in the way proposed. Scott also discusses potential limitations of using his survey data and mentions other explanations and challenges to the original finding. Shorter summary

Scott Alexander announces the results of the 2022 ACX survey, providing links to questions, results, and downloadable datasets, with notes on privacy measures and future analyses. Longer summary

This post announces the results of the 2022 Astral Codex Ten survey, which had 7,341 participants. Scott Alexander provides links to the survey questions and results, and offers downloadable datasets for public use. He mentions that more detailed analyses will be published over the coming year. The post also includes information on data anonymization measures taken to protect respondents' privacy, and notes some limitations and peculiarities in the data collection process. Scott encourages readers to explore the data themselves and offers to provide more complete information upon request. Shorter summary

Scott Alexander announces Stage 2 of the 2023 Prediction Contest, encouraging participants to use any resources to make accurate predictions. Longer summary

Scott Alexander announces Stage 2 ('Full Mode') of the 2023 Prediction Contest, following the closure of Stage 1 ('Blind Mode'). In this stage, participants are encouraged to use any resources available to make accurate predictions, including personal research, prediction markets, forecasting tournaments, and the 3295 blind mode answers from Stage 1. Scott provides suggestions on how to use these resources and emphasizes that there's no such thing as cheating, except for time travel or harming competitors. He also mentions that the form will ask for a brief description of the strategy used. Shorter summary

Scott Alexander investigates whether non-religious people are more prone to believing conspiracy theories, finding a U-shaped relationship between religiosity and skepticism. Longer summary

Scott Alexander examines the claim that non-religious people are more likely to believe in conspiracy theories and woo. He analyzes various studies on beliefs in UFOs, Bigfoot, and astrology across different religious groups. The results show a more nuanced picture: both strongly religious people and outright atheists are generally less likely to believe in these theories, while those in the middle (weakly religious or agnostic) are more susceptible. Scott discusses possible explanations for this pattern, including intellectual coherence and closed-mindedness. He concludes that the relationship between religiosity and belief in conspiracy theories is more complex than commonly assumed. Shorter summary

Scott Alexander shares reader comments on his 'San Fransicko' book review, covering homelessness, crime statistics, and urban policy debates. Longer summary

This post is a collection of highlights from reader comments on Scott Alexander's review of the book 'San Fransicko'. It covers various topics related to homelessness, crime, and urban policy in San Francisco and other cities. The comments provide additional context, personal anecdotes, data analysis, and critiques of both the book and Scott's review. Key themes include the complexity of homelessness, issues with crime statistics, debates over housing policy, and differing perspectives on how to address urban problems. Shorter summary

Scott offers corrections about Polymarket's status and updates on the 2022 prediction contest, including calls for collaboration and ideas. Longer summary

Scott Alexander provides two corrections and updates to previous posts. First, he clarifies that Polymarket is still operational, offering real-money markets outside the US and working on a US-compliant product. Second, he reminds readers about the 2022 prediction contest entry deadline and shares a message from the contest organizers about potential collaborations with prediction markets and ideas for using the contest data. Shorter summary

Scott Alexander conducts a personal randomized controlled trial of a sleep supplement, finding no significant effect over placebo, but gains insights into his sleep patterns. Longer summary

Scott Alexander conducts a personal randomized controlled trial to test the effectiveness of a sleep supplement called Sleep Support. Initially, he experiences a dramatic improvement in his sleep patterns, but decides to rigorously test this effect. He designs an experiment using placebo pills and blind administration over 24 nights. Surprisingly, the results show no significant difference between the Sleep Support and placebo nights in terms of sleep duration, wake-up time, or subjective measures. Scott concludes that his initial perceived improvement was likely due to the placebo effect and the act of not checking the clock upon waking. Despite the supplement not outperforming placebo, Scott considers the experiment a success as it led to improved sleep habits. Shorter summary

Scott Alexander analyzes survey data to investigate whether assortative mating among highly analytical people increases autism risk in their children, finding no significant evidence for this hypothesis. Longer summary

Scott Alexander investigates whether assortative mating among highly analytical people in Silicon Valley increases the risk of autism in their children. He uses data from the 2020 Slate Star Codex survey, which included 8,043 respondents from highly analytical backgrounds. The study found that while the sample had higher rates of autism (4-8%) than the general population (2.5-5%), there was no significant increase in autism rates among children of couples where both partners were highly analytical. The autism rate for children in the sample was 3.7-5.2%, with only 0.6% having severe autism. Scott concludes that while the study has limitations, it provides evidence against strong versions of the assortative mating hypothesis for autism risk. Shorter summary

Scott Alexander presents the results of the 2020 Slate Star Codex survey, including links to data, privacy measures, and future analysis plans. Longer summary

This post announces the results of the 2020 Slate Star Codex survey, which received 8,043 responses. Scott Alexander provides links to the survey questions and aggregated results, addresses privacy concerns by removing long-answer questions from public view, and offers downloadable datasets for those interested in analyzing the data themselves. He mentions plans for publishing more complex analyses over the coming year. The post also includes the results of a game from the survey, 'Prisoner's Dilemma Against Your Clone', and instructions for the winner to claim their prize. Shorter summary

Scott Alexander partially retracts and corrects his previous findings on age gaps and birth order effects after errors were identified in his analysis. Longer summary

Scott Alexander partially retracts his previous findings on age gaps and birth order effects. He acknowledges that Bucky, a Less Wrong user, found errors in his analysis of SSC survey data. While the original conclusion about firstborn children being overrepresented in high-openness STEM types remains valid, the specific findings about age gaps were partially incorrect. Scott explains the errors, presents Bucky's corrected analysis, and discusses the implications. He emphasizes the importance of data transparency and encourages readers to double-check his work. Shorter summary

Scott Alexander follows up on his critique of a book about the Baumol effect, presenting data that challenges the book's claims about rising wages driving cost increases in education and healthcare. Longer summary

Scott Alexander follows up on his review of Tabarrok and Helland's book about the Baumol effect and rising costs in education and healthcare. He expresses disappointment with Tabarrok's response to his critique and further explores the issues. Scott presents data showing that wages in high-productivity sectors and for doctors and teachers have not risen as much as claimed, which challenges the book's central thesis. He also clarifies his understanding of how the Baumol effect can make things less affordable for individuals even if not for society as a whole. The post analyzes various data sources and graphs to support these points, maintaining a critical stance towards the original book's arguments. Shorter summary

Scott Alexander analyzes birth order effects in SSC readers, finding strong effects for sibling age gaps of 1-7 years, with a significant drop-off after 7 years. Longer summary

Scott Alexander investigates birth order effects using data from the 2019 Slate Star Codex survey. He finds that firstborns are overrepresented among SSC readers, replicating previous findings. The study focuses on how age gaps between siblings affect this birth order effect. Results show strong effects for age gaps of 1-7 years, with a dramatic decrease for gaps larger than 7 years. Scott discusses possible explanations for these findings, including intra-family competition and parental investment hypotheses. He notes that the results don't seem consistent with some other proposed mechanisms like maternal antibodies or vitamin deficiencies. The post ends with a call for further replication and expansion of these results. Shorter summary

Scott Alexander tests the claim that mathematicians' preference for algebra or analysis predicts their corn-eating style, finding no significant correlation in a survey of over 2,600 respondents. Longer summary

Scott Alexander investigates a claim made by Ben Tilly that mathematicians' preference for algebra or analysis predicts how they eat corn (in rows or spirals). Scott included questions about math preference and corn-eating style in his 2019 Slate Star Codex reader survey. Analyzing 2,683 responses, including a subset of PhD mathematicians, he found no significant correlation between math preference and corn-eating style, contradicting Tilly's observation. Scott suggests the original claim might be due to the power of suggestion or selective memory. He also explores demographic factors influencing corn-eating styles, finding some cultural differences but no clear explanation for the variability. Shorter summary

Scott Alexander announces the results of the 2019 Slate Star Codex survey, providing links to the questions, results, and downloadable public datasets. Longer summary

This post announces the results of the 2019 Slate Star Codex survey, which was completed by 8,171 people. Scott Alexander provides links to view the survey questions and results, and mentions that more detailed analyses will be published over the coming year. He also offers downloadable datasets of the public responses for those who want to investigate the data themselves, noting that these datasets exclude some sensitive information and may not exactly match the full version. Shorter summary

Scott Alexander investigates the complexities of using Google Trends for mental health research, proposing methods to improve accuracy and interpretation of search data. Longer summary

Scott Alexander explores the challenges and nuances of using Google Trends for research, focusing on mental health-related searches. He demonstrates how individual keywords can be misleading and suggests averaging multiple related terms. Scott introduces a two-factor theory: one representing students' intellectual interest in mental health, which is declining, and another representing people with mental health issues, which is increasing. He discusses potential issues like temporal autocorrelation and provides tips for using Google Trends effectively, including the importance of considering school-related search patterns and the lack of need to adjust for general intellectual decline on the Internet. Shorter summary

Scott Alexander reports on a survey about nighttime ventilation interventions, finding modest overall improvements but some individual success stories. Longer summary

Scott Alexander presents the results of a survey on nighttime ventilation conducted after his previous post on carbon dioxide levels. The survey, with 129 participants, explored various interventions to improve sleep quality by reducing CO2 levels. While the overall results were modest, with an average improvement of 1.4 on a 0-5 scale, some participants reported significant benefits. The most common intervention was sleeping with an open window. Despite the underwhelming results, most participants planned to continue their interventions. Scott concludes that the results are essentially negative, both for nighttime ventilation and for the reliability of informal blog surveys in producing confident data. Shorter summary

Scott summarizes and responds to comments on his technological unemployment article, covering various debates, critiques, and potential explanations for observed trends. Longer summary

This post summarizes comments on Scott's previous article about technological unemployment. It covers various perspectives on the topic, including debates about the pace of technological change, the impact of women entering the workforce, the role of disability benefits, issues with data interpretation, historical comparisons, and potential future scenarios. Scott also addresses some critiques of his original analysis and acknowledges areas where further research is needed. Shorter summary