The Ledger
Every statement that passed quotation and attribution checks. Mix any filter with any other: certainty 1/5, debate potential 5/5, or both at once.
why aren't all 22 resolved? a statement only gets an assessment when the public record can support or contradict it. opinions and what-ifs never can, and 0 checkable ones are still open, waiting for their date. predictions held up or didn't; assertions are supported or contradicted. on every card: ▮▮▮▮▮ certainty · ▮▮▮▮▮ debate potential. speakers are clickable
Simkin: Call-out culture incentivizes finger-pointing regardless of expertise
“The big problem with call out culture is that we're rewarding people just for the call out. That it doesn't matter what their other behavior it is. It doesn't matter what other positions they have, what knowledge they have, what expertise they have. They just …”
Simkin: Probabilistic forecasts cannot be judged wrong unless 0% or 100%
“It's really hard to say anybody's wrong about a single probability prediction, unless they said that something was zero percent or a hundred percent.”
Simkin: Constructive communication beats probabilistic thinking for truth-finding
“Talk more is number one. That beats probabilistic thinking that, you know, that, that beats sort of anything else in truth finding is, is being able to bring in other people in the decision process in a constructive way.”
Simkin: Traders should not back limited opinions against informed counterparties
“Our approach is to recognize that we are often on the bad end of informational asymmetry that other people who are looking to trade in the markets frequently know more than we do. And as a result, we don't want to back our own limited opinion against a more in…”
Simkin: Decision-makers must update opinions in a Bayesian way
“The most important thing from our perspective is to be willing to update that opinion in a Bayesian way, to use approaches that are going to be inclusive of all the information available to us, and only when we get to mutually exclusive information or mutually…”
Simkin: Use related instruments to find disconfirming evidence before taking trades
“And again, in isolation, it's really hard for me just to say this person's wrong. But if I have a similar looking option, similar because it's the same expiration, or because it's the same strike and a different expiration, or that there's something about the …”
Simkin: Strict binary rules reduce cognitive load better than flexible principles
“It's so much easier if you have a rule than if you try to have a principle, right? That I don't eat dessert is so much easier than each time that you have the opportunity to have dessert to say, well, I don't eat a lot of dessert. Is this one of the times that…”
Todd Simkin: SIG operates on the belief that traders are made, not born
“Susquehanna has always had a very growth mindset perspective on, on teaching trading, you know, before Carol Dweck had even shared her views on growth mindset. That is, that has always been the company's position is that traders are made, not born.”
Simkin: Effective mentorship models the decision process rather than prescribing actions
“And a big part of how information is passed from the mentor to the mentee is by modeling the decision process. It is not enough to say you should have raised vol by two points when this trade came in. Instead, it's so much more important to say, okay, when thi…”
Simkin: Trading is running continuous experiments where failure drives success
“In the world that I live in, you know, for better or worse, we know that we're going to make mistakes all the time, that we are effectively just running experiments and getting feedback and then updating our approach and running a new experiment again the next…”
Simkin: The worst probabilistic forecasts come from media-incentivized experts
“The worst forecasts are often from people who are experts who make extreme forecasts. You know, when they're right, they're going to look really right because they said something extreme. And that means that they're going to get on the news program.”
Simkin: Asking for feedback without acting on it is actively harmful
“If you get feedback and then don't do anything with it, people are going to stop giving you the feedback. It's not just not helpful to ask for feedback and not change it. It's actually hurtful.”
Simkin: Assuming counterparties know what they are doing protects traders
“On the trading side, sort of this principle of charity is really giving somebody credit for knowing what they're doing when they're trading against you. This is what sort of protects you from being run over by somebody who has better information than you do.”
Simkin: Negotiations are collaborative because counterparties can always walk away
“Every single negotiation is a cooperation and a collaboration. But there's not a single time where I'm almost never, and really, you know, probably never, where the other person has to negotiate with you. They have some alternative. They can walk away, which m…”
Simkin: The best job interviews leave candidates wishing for a do-over
“The best outcome for me for an interview is if the candidate walks away and wishes they could have part of the interview back.”
Simkin: Susquehanna requires traders to continuously vocalize their decisions to peers
“A big part of our approach to education is to teach people to talk through their decisions and to talk about why they're doing what they're doing with their peers, the other people on their team.”
Simkin: Susquehanna shields feedback providers from knowing a trade's financial outcome
“When people talk about trading decisions that they've made to more experienced traders or to peers who can give them feedback on it, we do everything we can to shield The person giving feedback from knowing the results.”
Simkin: Calibrating forecasts requires frequent, uncorrelated repetitions and feedback
“If the only thing that you predict are very hard to predict outcomes and you predict them very rarely, you're not going to be able to calibrate very well at all. On the other hand, if you predict many different things that particularly if they're uncorrelated,…”
Simkin: Weather forecasters are exceptionally well-calibrated in probability assessments
“Weather forecasters are really good. I mean, just stupid good. And if you were to plot how often it rains when they say there's a 30% chance of rain, it's like 30% of the time. It's not 25 or 35.”
Simkin: Susquehanna's founders tested decision principles in Vegas poker before trading
“The founders of Susquehanna were in college together. And they studied an array of subjects, but what really brought them together was that they played poker together and were able to talk about the decision process in their poker game in, in a really nice way…”
Simkin: Jeff Yass threatened to fire him over bad Jeopardy wagers
“Jeff Yoss, the founder of, you know, one of the founders of Susquehanna, the chief risk manager at Susquehanna came into my office. Before I went and he said, Todd, nobody cares if you know anything about American history, but if you screw up the betting on, o…”
Simkin: Joined SIG with no finance knowledge after studying deaf culture
“I joined Susquehanna in 1997 straight out of college. I went to University of Virginia undergrad. Unlike sort of the stereotypical finance background, I studied a combination of anthropology, psychology, linguistics, and education. And I, it was combined into …”