Hi, I’m Spencer! On this website, you’ll find more than 300 essays I’ve written about psychology, philosophy, society, critical thinking, mathematics, and technology.
You can find information about my book, The 12 Levers, here. It’s about all the ways you can improve your life via psychological strategies, based on years of research we conducted.
In terms of my work, I’m the founder and CEO of Spark Wave (we conduct psychology research and create new psychology-related products to help solve important problems). For instance, we created:
- Clearer Thinking (offering numerous free tools for helping you make better decisions and reduce biases)
- Transparent replications (rapid replications of psychology and behavioral studies for more reliable research)
- Hypothesize (effortlessly conduct data analysis, data science, and statistics in minutes in your web browser)
- Guided Track (a platform for building behavior change interventions and complex social science studies)
- Positly (a platform for recruiting study participants for human subjects research, social science, and product research)
- Mind Ease (for rapid anxiety relief whenever you need it)
- Thought Saver (a tool for helping you build your perfect daily routine and remember everything important that you learn)
- PersonalityMap (a platform that lets you explore over 1 million human correlations spanning personality, demographics, behavior, and beliefs)
- Nimble Python Package (a unified framework for data science, data analysis, and machine learning in Python that can be used as a more elegant alternative to the standard numpy/pandas/sklearn stack)
- Society Explained (a website that allows you to efficiently explore different theories of society as proposed by over 100 thinkers)
We also run studies on many topics in psychology, such as decision-making, biases, personality, and mental health.
I have a Ph.D. in applied math from the Courant Institute of Mathematical Sciences at NYU, with my specialty being machine learning / artificial intelligence. I also have a bachelor of science degree from Columbia University, where I studied applied math and computer science. My doctoral thesis is called Machine Learning at Extremes.
I’ve published papers on a variety of topics in applied math, machine learning, mental health, and social science:
- Hypothesis Set Stability and Generalization
- The Immediate Impact of App-based Psychotherapeutic Exercises on Anxiety: An RCT
- AI can outperform humans in predicting correlations between personality items
- Relative deviation learning bounds and generalization with unbounded loss functions
- Donors vastly underestimate differences in charities’ effectiveness
- Nudging Resisters Toward Change – Self-Persuasion Interventions for Reducing Attitude Certainty
- Development and Validation of the Fatigue State Questionnaire
- Level Sets of Arbitrary Dimension Polynomials with Positive Coefficients and Real Exponents
- Public attitudes and literacy about posttraumatic stress disorder in U.S. adults
- Tight lower bound on the probability of a binomial exceeding its expectation
- Introducing the Decision Advisor: A simple online tool that helps people overcome cognitive biases and experience less regret in real-life decisions
- Most of Us Combine Personality Traits from Different Genders (Scientific American)
- Personality Tests Aren’t All the Same. Some Work Better Than Others (Scientific American)
- Calibration Scoring Rules for Practical Prediction Training (unpublished white paper)
In 2009, I co-founded Ask A Mathematician / Ask A Physicist, a site where we answered people’s philosophical math and physics questions, which is now entirely run by “the Physicist.”
In 2005, I co-founded Rebellion Research, a quantitative investment firm applying machine learning techniques to investing in stocks and ETFs. Many years ago, I decided to leave the firm to focus on other interests.
For fun, in 2026, I made The Stranger’s Games, which is a web-based game consisting of 25 mini-games (it only works on desktop computers).
You can learn a bit more about my work in an FAQ here.
Note that my name is spelled “Spencer Greenberg” not “Spencer Greenburg” 🙂