Published and Forthcoming Papers
"Using List Prices to Collude or to Compete?" (with Juan-Pablo Montero). Economic Journal (2024).
[Slides] [Accepted manuscript] [Policy coverage] [NotebookLM (decent but imperfect)]
Abstract: It is often argued that collusion is not possible in wholesale markets where suppliers and buyers privately bargain over discounts off list prices and sales quotas are unfeasible. In many wholesale markets, however, there are buyers of varying sizes and bargaining powers who compete for final consumers in the retail market. We study the role of public announcements of list prices in this wholesale-retail setting, whether suppliers collude or compete. Two effects are at work. When suppliers collude, public announcements of list prices further extend the possibility of collusion from small to large buyers (the multibuyer contact effect). When suppliers compete, these public announcements provide them with commitment to negotiate better terms with large buyers (the commitment effect).
"Effects of mindfulness-based stress reduction on psychological distress in health workers: A three-arm parallel randomized controlled trial" (with Antonia Errázuriz, Kristin Schmidt, Eduardo A. Undurraga, Sebastián Medeiros, Rene Baudrand, Marcela Henriquez, Pablo Celhay, and Rodrigo A. Figueroa). Journal of Psychiatric Research (2022).
[NotebookLM (decent but imperfect)]
Abstract: Mindfulness-based Stress Reduction (MBSR) has shown good efficacy for improving wellbeing in employees experiencing occupational stress. However, comparisons with other interventions, longer-term follow-up, and data from varying sociocultural contexts are lacking. This three-arm, parallel randomised controlled trial (RCT) examined the effects of MBSR on psychological distress in non-physician health workers in direct contact with patients. 105 participants were randomly allocated to either: (1) MBSR (N = 35), (2) Stress Management Course (SMC; N = 34) or (3) wait-list (N = 36). Participants and those assessing outcomes were blinded to group assignment. Participants completed questionnaires pre- and post-intervention and four months after the intervention. Psychological distress was measured using the General Health Questionnaire (GHQ-12) and Outcome Questionnaire (OQ-45). Secondary outcomes included perceived stress, job satisfaction, mindfulness skills and changes in salivary cortisol. 77 participants completed measures post-intervention and 52 at 4-month follow-up. MBSR showed a post-intervention effect in reducing GHQ-12 (ß = −0.80 [SE = 1.58] p < 0.01) and OQ-45 (ß = −0.72, [SE = 5.87] p < 0.05) psychological distress, compared to SMC and in reducing GHQ-12 (ß = −1.30 [SE = 1.38] p < 0.001) and OQ-45 (ß = −0.71, [SE = 5.58] p < 0.01) psychological distress compared to wait-list condition. In our secondary outcome, only MBSR was associated with a decrease in the cortisol awaking response by 23% (p < 0.05). At follow-up, only effects of MBSR on the psychological distress ‘social role’ subscale (ß = −0.76 [SE = 1.31] p < 0.05) remained significant, compared to SMC. In conclusion, MBSR appears useful in reducing short-term psychological distress in healthcare workers, but these effects were not maintained at follow-up.
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Working Papers
"Nash-in-Nash Equilibrium with Inefficient Contracts" (with Moeen Nehzati).
[New draft coming soon]
Abstract: Inefficient contracts between firms and suppliers - contracts that do not maximize gains from trade - are ubiquitous. Research on bilateral oligopolies with inefficient contracts commonly employs the Nash-in-Nash bargaining equilibrium concept, but has been hampered by a lack of theoretical foundations for this equilibrium concept. We provide conditions for the existence and uniqueness of Nash-in-Nash equilibria in vertical relations games. These conditions imply that bargaining models are point identified, and can be verified in empirical work. We also provide an algorithm for fast equilibrium computation. These results advance our theoretical understanding of bilateral oligopolies and extend the toolset available to empirical researchers.
"Inference From Random Restarts" (with Moeen Nehzati).
Abstract: Algorithms for computing equilibria, optima, and fixed points in nonconvex problems often depend sensitively on practitioner-chosen initial conditions. When uniqueness of a solution is of interest, a common heuristic is to run such algorithms from many randomly selected initial conditions and to interpret repeated convergence to the same output as evidence of a unique solution or a dominant basin of attraction. Despite its widespread use, this practice lacks a formal inferential foundation.
We provide a simple probabilistic framework for interpreting such numerical evidence. First, we give sufficient conditions under which an algorithm's terminal output is a measurable function of its initial condition, allowing probabilistic reasoning over outcomes. Second, we provide sufficient conditions ensuring that an algorithm admits only finitely many possible terminal outcomes. While these conditions may be difficult to verify on a case-by-case basis, we give simple sufficient conditions for broad classes of problems under which almost all instances admit only finitely many outcomes (in the sense of prevalence). Standard algorithms such as gradient descent and damped fixed-point iteration applied to sufficiently smooth functions satisfy these conditions.
Within this framework, repeated solver runs correspond to independent samples from the induced distribution over outcomes. We adopt a Bayesian approach to infer basin sizes and the probability of solution uniqueness from repeated identical outputs, and we establish convergence rates for the resulting posterior beliefs. Finally, we apply our framework to settings in the existing industrial organization literature, where random-restart heuristics are used. Our results formalize and qualify these arguments, clarifying when repeated convergence provides meaningful evidence for uniqueness and when it does not.
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Work in Progress
"Design of Emissions Trading Systems" (with Niklas Schoch ).
"Prevalence Results for Economics and Game Theory" (with Moeen Nehzati).
"Determinants of Fiscal Capacity in Early Modern Europe".