Ben Davies

Anirudh and I have a new paper.

I make pancakes from scratch most mornings.

Today I’ll speak at an event run by the Stanford Economics Association.

In one of my favorite papers (summarized here), Carnehl and Schneider (2025) study the choice between two types of research: research that “deepens” our knowledge by filling gaps between answered questions; research that “expands” our knowledge by answeri…

On this week’s episode of the ReThinking podcast, Adam Grant describes how people sabotage themselves: “Let’s say you’re going into a difficult math test and you’re afraid of finding out that you’re not smart enough to do it.

Suppose I borrow \(B_0\) at an annual interest rate of \(r\).

This post summarizes the past two years of my PhD program.1 I describe my research and teaching experience, and offer some advice to other students.

Statistical models have a formal definition: they comprise (i) a sample space and (ii) a probability distribution (or set of distributions) over that space.

Armchair Expert is a podcast hosted by Dax Shepard and Monica Padman.

Let \(A\) be the \(n\times n\) matrix with \({ij}^\text{th}\) entry \(A_{ij}=\min\{i,j\}\).

Suppose I want to retire at time \(T>0\).

I have a new paper on Bayesian learning.

Suppose I want to learn the value of a parameter \(\theta\in\mathbb{R}\).

A (standard) Wiener process is a continuous-time stochastic process \(\{W(t)\}_{t\ge0}\) with initial value \(W(0)=0\) and instantaneous increments $$\newcommand{\der}{\mathrm{d}} \der W(t)\sim N(0,\der t).$$ We can simulate such a process as follows.

Let \(0<x_1<x_2<\ldots<x_n\) and let \(A\) be the symmetric \(n\times n\) matrix with \({ij}^\text{th}\) entry \(A_{ij}=\min\{x_i,x_j\}\).1 This matrix has linearly independent columns and so is invertible.

Let \(X=(X_1,X_2)\) be a random vector in \(\mathbb{R}^2\).

This post is about waiting for information before taking an action.

This post describes a continuous-time model of Bayesian learning about a binary state.

Suppose my payoff \(u(a,\mu)\equiv-(a-\mu)^2\) from taking an action \(a\in\mathbb{R}\) depends on an unknown state \(\mu\in\mathbb{R}\).1 I can learn about \(\mu\) by collecting data \(X=\{x_1,x_2,\ldots,x_n\}\), where the observations \(x_i\) are iid no…

Suppose I receive a noisy signal \(s\in\{0,1\}\) about an unknown state \(\omega\in\{0,1\}\).

Imagine two portfolios of S&P 500 companies.

In this week’s episode of EconTalk, Tyler Cowen asks: “Is there any actual mathematical model of this process of how the world is supposed to end?

Here’s a summary of my website’s traffic since the start of 2023: Notice the spike on April 9, when Tyler Cowen linked to my post of Marginal Revolution metadata.

Suppose I take out a loan.

Today I released the R package MRposts.

Today marks five years since my first blog post.

Economists often use fixed effects to correct for selection bias.

People talk for many reasons.

This week’s Riddler Classic asks us to fend off an alien invasion: The astronomers of Planet Xiddler are back in action!

We often use others’ opinions to guide our choices.

stravadata is an R package I use to organize and analyze my Strava activity data.

IndianVillages is a new R package containing data on social networks in rural India.

My previous post discussed how I should pace myself in a running race.

Suppose I’m running a race.

Suppose I have data \((a_i,b_i)_{i=1}^n\) on two random variables \(A\) and \(B\).

People tend to be less popular than their friends.

This post shows how binary random variables can be defined by their mean, variance, and skewness.

A crop farmer wonders if he should use a new fertilizer.

One of the requirements for my PhD program is to write a “second-year paper.”

Dollar cost averaging (DCA) is a way to split a lump sum investment into many smaller investments.

Yesterday Science published a study on social networks and job mobility.

This post summarizes the first two years of my PhD program.1 I discuss my first- and second-year coursework, and my quality of life as a grad student.

In a previous post, I showed that if the truth doesn’t matter then I’m better off being an ideologue with ideological friends.

I published my first blog post in March 2018.

Last month I visited New Zealand for the first time since moving to the USA.

Research is a cumulative process.

People learn socially: they get information from their friends.

I have a new paper on gender sorting in economic research teams.

My previous post showed that NBER research programs with higher female representation tend to have fewer papers published in the “Top Five” economics journals.

The latest version of nberwp (1.2.0) contains information on where NBER working papers are published: Outlet Papers Share (%) Top Five journals 3,832 12.7 Other journals 14,792 49.2 Book/chapters 3,096 10.3 Unpublished 8,363 27.8 About 62% of working pape…