EA - Samotsvety Nuclear Risk update October 2022 by NunoSempere

Link to original articleWelcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: Samotsvety Nuclear Risk update October 2022, published by NunoSempere on October 3, 2022 on The Effective Altruism Forum. After recent events in Ukraine, Samotsvety convened to update our probabilities of nuclear war. In March 2022, at the beginning of the Ukraine war, we were at ~0.01% that London would be hit with a nuclear weapon in the next month. Now, we are at ~0.05%/month. At the end of the post, we reflect on the size of our update, and what this means about our accuracy. Expected values are more finicky and more person-dependent than probabilities, and readers are encouraged to enter their own estimates, for which we provide a template. We’d guess that readers would lose 4 to 400 hours by staying in London in the next 1–3 months, but this estimate is at the end of a garden of forking paths, and more pessimistic or optimistic readers might make different methodological choices. We would recommend leaving if Russia uses a tactical nuclear weapon in Ukraine. Since March, we have also added our track record to samotsvety.org/track-record, which might be of use to readers when considering how much weight to give to our predictions. Question decomposition We have updated our decomposition to the following: What is the probability that Russia will use a nuclear weapon in Ukraine in the next MONTH? Conditional on Russia using a nuclear weapon in Ukraine what is the probability that nuclear conflict will scale beyond Ukraine in the next MONTH after the initial nuclear weapon use? Conditional on the nuclear conflict expanding to NATO, what is the chance that London would get hit, one MONTH after the first non-Ukraine nuclear bomb is used? For each of those questions, we also asked forecasters for their yearly probabilities. Following up on previous feedback, we also asked forecasters for their core reasons behind their forecasts, and we’ll present those alongside their probabilities. We also asked a range of questions about counterfactuals: Conditional on Russia NOT using a nuclear weapon in Ukraine, what is the probability of a nuclear conflict outside Ukraine in the next MONTH? Conditional on Russia NOT using a nuclear weapon in Ukraine what is the probability that nuclear conflict will scale beyond Ukraine in the next YEAR? Conditional on Russia NOT dropping a nuclear weapon in Ukraine in October, what is the probability that London will be hit with a nuclear weapon in October? As well as a sanity check: What is the unconditional probability of London being hit with a nuclear weapon in October? Summaries Summary tables For ≤ 1 month staggering times between each step Event Conditional on previous stepUnconditional probabilityRussia uses a nuclear weapon in Ukraine in the next month—Nuclear conflict scales beyond Ukraine in the next month after the initial nuclear weapon useLondon gets hit, one month after the first non-Ukraine nuclear bomb is used? 8.6% 4.5% 0.36% 14% 0.055% For ≤ 1 year staggering times between each step Event Conditional on previous stepUnconditional probabilityRussia uses a nuclear weapon in Ukraine in the next year— Nuclear conflict scales beyond Ukraine in the next year after the initial nuclear weapon useLondon gets hit, one year after the first non-Ukraine nuclear bomb is used? 23% 14% 3.2% 23% 0.75% Visualizations This time, we are also experimenting with providing a few visualizations. Their advantage is that they may be more intuitive; the disadvantage is that they may gloss over the shape of our uncertainty, and thus mislead. Reader beware. For the forecast with one month between each escalation step, we have: For our forecast with a maximum of one year between each escalation step, we have: A forecaster’s perspective In order to understand at what level we are forecasting here, we are providing forecasters’ comments. One forecaster prov...