Helena Perrone

Published  Papers

Chips in on a merger:  the Arm-Nvidia case, International Journal of Industrial Organization, 2025, 98: 103130.

Consumers' Costly Responses to Product-Harm Crises (joint with Rosa Ferrer),  Management Science, 2023, 69(5):2639-2671. 

Demand for nondurable goods: a shortcut to long-run demand elasticities, Rand Journal of Economics, 2017, 48: 856-873.

Consumers' quality choice during demand peaks, International Journal of Industrial Organization, 2016, 44: 154-162.

Gender Bias in Intrahousehold Allocation: Evidence from an Unintentional Experiment, joint with Luis B. Braido and Pedro Olinto,  Review of Economics and Statistics 2012, 94: 552-565

Working Papers

Demand steering through the smokescreen of stockouts: evidence from cigarette vending machines (with Pablo Casas  and Asis Martinez-Jerez) 

 We show evidence of retailers using stockouts to steer demand towards products with higher retailer margins. We consider a unique setting where regulation limits the use of vertical agreements that could weaken steering incentives, prices are set by manufacturers,  and product assortment is fixed in the short run. Using data on cigarette vending machines, we find empirical evidence consistent with retailers making strategic product re-stocking decisions. They exert less re-stocking effort for low-margin products, prompting consumers to shift purchases toward high-margin products. In a setting where prices vary infrequently, we exploit variation in product availability as a source of identification to recover preference parameters. Estimated diversion ratios are high across products within the same vending machine and low towards outside retailers. We also recover manufacturers' marginal costs. Counterfactual exercises based on our model parameter estimates measure the welfare effects of demand steering for consumers and manufacturers. On average, welfare losses are economically relevant; however, some manufacturers are better off under strategic stockouts.

Quality upgrade and the diffusion of innovation: Effects on Mobile Internet Usage (with Mattia Colombo and Eleftheria Triviza)

This paper examines the impact of a quality upgrade on the adoption rate of new technologies, exploiting the staggered transition from 3G to 4G in mobile internet usage in Greece. We use individual monthly mobile consumption data from a major Greek Internet Service Provider (ISP) spanning from 2011 to 2013.  Our results show that introducing 4G leads to a significant increase in mobile internet consumption, both among existing users and in attracting new users. This innovation accelerates the diffusion of mobile internet usage, particularly in areas with more technologically savvy consumers. Consumers start responding to the quality shock with a few months delay, and mobile internet usage increases gradually, suggesting a learning process. Furthermore, adoption rates are heterogeneous across the population and are driven by young men, who increase their use more than women and consumers aged over 40.

Drivers of Switching in Autoinsurance: Evidence from observable and exogenous consideration sets  (with Fabricio Valiati)

This paper studies switching behavior and its determinants in auto-insurance markets using a dataset that includes information on policyholder choices and their consideration sets, including alternative contract prices. We show that disregarding consumers' consideration sets and the price of alternative offers, especially the premium offered by the previous insurance at renewal, leads to an overestimation of choice inertia and an understatement of consumer price responsiveness. Our empirical evidence is consistent with inertia in the form of brand loyalty. We also find that previous claim history is a primary determinant of switching behavior, even after controlling for premium differentials and observed and unobserved characteristics of the contract and insurers. 

The value of platforms: Evidence from the American Airlines vs Expedia conflict (with Raquel Sampaio and Miguel Urdanoz)

This paper explores the welfare impact of intermediaries in the air ticket market, focusing on a 2010 conflict between airlines and online platforms. Using a difference-in-difference approach and transaction-level data, we find that the temporary withdrawal of American Airlines and Delta products led to the near elimination of high-search-cost interline products. This underscores the significant role intermediaries play in enhancing consumer welfare by reducing search costs.

Price dispersion and informational frictions: evidence from supermarket purchases (with Pierre Dubois) 

Traditional demand models assume that consumers are perfectly informed about product characteristics, including price. However, this assumption may be too strong. Unannounced sales are a common supermarket practice. As we show, retailers frequently change position in the price rankings, thus making it unlikely that consumers are aware of all deals offered in each period. Further empirical evidence on consumer behavior is also consistent with a model with price information frictions. We develop such a model for horizontally differentiated products and structurally estimate the search cost distribution. The results show that in equilibrium, consumers observe a limited number of prices before making a purchase decision, which implies that imperfect information is indeed important and that local market power is potentially high. We also show that a full information demand model yields severely biased price elasticities.

Gender Differences in Academic Performance: The Role of Negative Marking in Multiple-Choice Exams (joint with Patricia Funk) 

We investigate whether penalizing wrong answers on multiple-choice tests (``negative marking'') makes females relatively worse off compared to males (the comparison being no penalties for wrong answers). With a cohort of more than 500 undergraduate students at a major Spanish university, we conducted a field experiment in the Microeconomics course. We created a final exam, which was composed of two parts: one with penalties for wrong answers and one without. Students were randomly allocated to different exam permutations, which differed in the questions that carried penalties for wrong answers. We find that the penalties did not harm female students. Females performed better than males on both parts of the exam and did so to a greater extent on the part with penalties. Whereas risk aversion did not affect overall scores (despite affecting answering behavior), ability did. High-ability students performed relatively better with negative marking, and these were more likely to be women.

Work in progress

The Competitive Effects of Subprime Credit for Consumption

Using data from Brazil, I study the effect of entry of large subprime lenders in markets where the population was previously credit constrained on: (i) consumers’ purchase patterns; (ii)  consumers’ welfare measures; and (iii) the local competitive environment.