Which factors truly drive economic growth, such as investment, education or trade? Using 73 countries over four decades, we average across every possible combination of factors instead of betting on a single model, while allowing growth itself to shape those factors. This R tutorial comes with an interactive app that runs in your web browser.
Do carbon emissions first fall, then rise and then fall again as countries get richer? With 12 possible control variables there are thousands of possible models, so we use two data-driven methods that weigh or select the controls and test them on simulated data where we know the right answer. This Stata tutorial comes with an interactive app that runs in your web browser.
When a state raises cigarette prices, do smokers simply buy in the state next door? Using cigarette demand in 46 American states from 1963 to 1992, we measure how prices and income affect smoking at home and in neighboring states, and how habits carry over from year to year. This R tutorial comes with an interactive app that runs in your web browser.
How does credit risk spread across banks? Using quarterly data on 350 American banks from 2006 to 2014 in Stata, we model bad loans that spill over between similar banks, persist over time and respond to shared economic shocks, and show that ignoring those shocks gives misleading answers. It comes with an interactive app that runs in your web browser.
What does it really mean to control for a variable in a regression? We use a classic result from statistics to turn that idea into simple scatter plots, first with simulated data and then with real data that follows the same people over time. This R tutorial comes with an interactive app that runs in your web browser.
What does it really mean to control for a variable in a regression? In Stata, we turn that idea into a picture: we strip out the influence of other factors and plot what is left, using examples on store sales, airline flights and worker wages. It comes with an interactive app that runs in your web browser.
Does giving cash to poor households raise what they spend on everyday needs? Using a simulated randomized experiment with 2,000 households in Stata, we compare several ways of estimating the effect and see that all of them recover the true gain of about 12 percent. It comes with an interactive app that runs in your web browser.
Do cigarette prices in one state change how much people smoke in neighboring states? Using data on 46 American states from 1963 to 1992 in Stata, we model cross-border shopping and smoking habits, and find that ignoring neighbors understates how much prices matter. It comes with an interactive app that runs in your web browser.