arXiv subjects

Pallavi Pal

Publications and source records attributed to Pallavi Pal.

4 recordsLinked to original sources

arXiv2026

To Combine or Not? Consolidating Horizontal Acquisitions in Multi-sided Market

When a parent company acquires a horizontal competitor on the same side of a multi-sided market, it must decide whether to fully integrate the acquired platform or keep it as a separate brand. We study this in the context of Uber's acquisition of Postmates, using novel consumer receipt data that tracks food delivery spending. Employing an Age-Period-Cohort (APC) decomposition, we isolate the merger's effect on consumer spending while controlling for lifecycle and cohort effects. We find that Postmates users sharply reduced their spending on the platform after the merger, but spending shifted not only to UberEats, but also to competitors like DoorDash and Grubhub. Consumers who used multiple platforms and had low pre-merger activity on Postmates were more 'sticky', showing little change. Comparing our APC results with a standard Difference-in-Differences (DiD) design, we find the DiD underestimates the merger's total impact by missing market-wide effects. Our findings suggest that in multi-sided markets, keeping acquired platforms separate can be beneficial; dissolving them may push demand to competitors, and some sticky multihoming users may not shift spending at all.

econ.EM↗

arXiv2026

Algorithm or Creative? Disentangling Algorithmic Divergent Delivery from User Ad Preferences in Digital Platforms

Online advertising platforms host hundreds of thousands of A/B tests, but the platform's delivery algorithm routes each creative to the audience it predicts will engage. Every two-arm test therefore conflates the creative's effect with the algorithm's targeting response, and adjusting for the realized audience is biased because audience is a post-treatment mediator. We propose a three-arm design that adds an arm exposing the algorithm to the treatment metadata while holding the user-facing creative identical to control, separately point-identifying the algorithmic delivery and ad creative effects. In a live Meta campaign with a women-targeted text fragment, the algorithmic delivery channel raises female impression share by $+2.27$ ppt, while the visible creative leaves delivery composition statistically unchanged. A conventional two-arm test would attribute the entire delivery shift to the creative. The design isolates the contribution of platform's algorithm to the outcome which is separable from creative content.

econ.EM↗

arXiv2026

Partial Identification of the Valuation Distribution in Sequential English Auctions

This paper extends the incomplete model of Haile and Tamer (2003) from static English auctions to sequential English auctions. Because bidders may wait for future opportunities, the static condition that bidders do not let rivals win at beatable prices need not hold. We replace it with a dynamic opportunity-cost restriction, yielding nonparametric valuation bounds without solving a dynamic equilibrium. Sharp bounds are also characterized. We propose a novel moment-condition inversion estimator that pools auctions with heterogeneous bidder counts, mitigating finite-sample instability of order statistics approaches and admitting analytical standard errors and smooth confidence intervals. Applications to Korean wholesale used-car auctions and Cars and Bids online auctions deliver informative bounds. Counterfactual analyses show that the option to wait lowers first-period revenue by 8--11% in the Korean market, that increasing effective competition from 8 to 20 serious bidders in Cars and Bids raises seller revenue by 40--65%, and that maximin reserve prices vary substantially across vehicle clusters.

econ.EM↗

arXiv2024

The Benefits from Bundling Demand in K-12 Broadband Procurement

We study a new market design for K-12 school broadband procurement that switched from school-specific bidding to a system that bundled schools into groups. Using an event study approach, we estimate that the program reduced internet prices by \$9.17 (55\%) per Mbps per month while increasing bandwidth by 380.06 Mbps (136\%). These benefits resulted primarily from mitigating exposure risk in broadband procurement - the risk that providers win too few contracts to cover their fixed infrastructure costs. Using a bounds approach, we show robustness of our estimates and document that participants saved between \$1.61 million and \$3.48 million, while their existing federal E-rate subsidy was \$2.47 million, and experienced substantial welfare gains.

econ.GN↗