I am an assistant professor in Wharton's Business Economics and Public Policy group working on empirical
industrial organization, with a focus on antitrust and the digital economy. I am also a Faculty Research
Fellow at the NBER. Before Wharton, I was a
Postdoctoral Researcher at Microsoft Research New England, and obtained my PhD in Economics at Princeton
University.
To match volatile demand with fixed capacity, cloud computing platforms employ tiered reliability—offering
discounted spot compute services from which users can be “evicted” (i.e., interrupted) with little warning
when capacity tightens. We study this market design using proprietary data from a major cloud platform,
exploiting a price experiment and the quasi-random nature of evictions to estimate a structural model. The
price elasticity of demand is -0.5, and evictions persistently reduce usage by 40%, indicating a strong
revealed preference for reliability. More usage increases eviction rates, consistent with congestion. We
interpret these facts through a model where heterogeneous users choose the compute reliability for each
workload, while learning about eviction risk through experience. On the supply side, evictions arise
endogenously given fixed capacity. Preliminary counterfactual results suggest that tiered reliability
provides Pareto gains relative to simply allowing the market to clear through congestion.
How do the productivity effects of AI evolve across successive generations of tools, and to what extent do
task-level gains ultimately translate into final output? We study these questions in the context of
software development, using data on more than 500,000 GitHub developers combined with their AI usage
telemetry. In a matched event study design, we find that autocomplete, interactive coding agents, and
autonomous coding agents each significantly increase coding activity (“commits”), with respective
cumulative effects of 30%, 180%, and 240%. These gains, however, attenuate sharply across the production
hierarchy: the 240% cumulative effect falls to 80% for the number of projects, and to 30% for actual
releases. This pattern is consistent with the weak-link hypothesis: the strong productivity gains from AI
are attenuated by human bottlenecks in the production chain, with an estimated elasticity of substitution
of 0.23 between AI and human effort, which indicates strong complementarities. We further confirm these
results across four major software marketplaces, finding a sharp increase in the number of new apps but no
increase in total usage. Large task-level AI productivity gains have therefore translated only partially
into shipped and used software thus far.
We study the forces behind Google’s large web-search market share. We develop a demand model with
switching costs, quality beliefs, and inattention, and estimate it using a field experiment. We find that
(i) requiring active choice barely increases Bing’s market share; (ii) Google users paid to try Bing
update positively about its quality and many prefer to continue using it; (iii) many Google users
defaulted into Bing do not switch back, consistent with inattention. Counterfactuals suggest that
eliminating demand frictions doubles Bing’s market share. Successful remedies expose users to alternative
search engines, while data sharing mandates have small effects.
This paper investigates concerns that vertically integrated platforms like Amazon steer demand towards
their own offers via algorithmic prominence, potentially harming consumers. On Amazon, for each product,
the Buybox prominence algorithm selects one seller to feature, influencing which offers consumers
consider. Using novel Amazon sales and Buybox (prominence) data, we estimate a structural model capturing
the effects of such algorithmic prominence on consumer choices, seller pricing, and entry. We find that
the platform can indeed steer demand as 95% of consumers consider only the Buybox offer. The Buybox is
highly price-elastic (−21), but skews towards Amazon’s own offers, which are featured as frequently as
observably similar offers priced 5% cheaper. Still, as consumers prefer these offers, this skew does not
amount to self-preferencing in the sense of harming consumers: consumer surplus is roughly maximized at
the estimated Amazon Buybox advantage, which balances higher prices against showing consumers their
preferred offers.
We develop a method for detecting cartels in multistage auctions. Our approach allows a firm to be
collusive when facing members of its cartel yet competitive when facing others. Intuitively, as initial
bids are shaded, close initial bids not only imply similar costs but also provide an incentive to
undercut. We detect firm pairs that ignore this incentive when facing each other. Our algorithm predicts
Ukraine's Antimonopoly Committee's sanctions: firm pairs classified as collusive are 8.98 times more
likely (standard error 2.65 times) to be sanctioned. It also uncovers additional collusion: 1,857
collusive firms participate in 15.57% of auctions, increasing costs by 1.95%.
As the economy digitizes, menu costs fall, and firms can more easily monitor prices. These trends have led
to the rise of automated pricing (and re-pricing) tools. We employ a novel e-commerce dataset to examine
the effect of algorithmic pricing in the wild. Evidence from an event study suggests that firms that start
employing repricing tools drop their prices by 16.93%, with market prices falling by 9.67%. However,
algorithmic pricing companies have developed ‘resetting’ strategies (which regularly raise prices in the
hope that competitors will follow) in order to avoid stark Bertrand-Nash competition. We find that these
strategies are effective at coaxing competitors to raise their prices: when a resetting strategy is
adopted on a market with less than six serious competitors, both competitor prices and market prices
eventually increase by 11.4%. While the resulting patterns of cycling prices are reminiscent of
Maskin-Tirole’s Edgeworth cycles, a model of equilibrium in delegated strategies fits the data better.
This model suggests that the average price over the cycle will be the monopoly price. Moreover, if the
available repricing technologies remain fixed, cycling and prices could rise significantly. However,
cycling is still relative rare in the data, even when studying a convenience sample of products with at
least one merchant using a repricing tool.
This study evaluates the effect of generative AI on software developer productivity via randomized
controlled trials at Microsoft, Accenture, and an anonymous Fortune 100 company. These field experiments,
run by the companies as part of their ordinary course of business, provided a random subset of developers
with access to an AI-based coding assistant suggesting intelligent code completions. Though each
experiment is noisy and results vary across experiments, when data is combined across three experiments
and 4,867 developers, our analysis reveals a 26.08% increase (SE: 10.3%) in completed tasks among
developers using the AI tool. Notably, less experienced developers had higher adoption rates and greater
productivity gains.
We analyze a vote-buying setup where a committee votes on a proposal important to the vote buyer. We
characterize the cheapest combination of bribes that guarantees the proposal's passing in different voting
environments. We find that the vote buyer publicly offers small bribes to a large supermajority of members
for both simultaneous and sequential votes. Each member accepts because he anticipates that the proposal
will pass regardless of his vote. We discuss the committee design that maximizes capture cost: combining
demanding majority requirements with diversity among members makes the committee more expensive. In small
committees, sequential voting increases cost, but the opposite is true for large committees. On the other
hand, additional members and transparent voting rules lower the cost.
(PDF of Old Version with
Additional Examples.)