
Research
Publications in refereed journals
“Local taxation and tax base mobility : Evidence from France”, T. Ly, S. Paty, Regional Science and Urban Economics, 2019.
Working Paper available as: GATE Working Paper
Local taxation and tax base mobility : Evidence from France
Abstract
This paper investigates the impact of tax base mobility on local taxation. First, we develop a theoretical model in order to examine the connection between local business property taxation and tax base mobility within a metropolitan area. We and that, in the presence of a budget compensation, decreasing capital intensity in business property tax base, composed of capital and land, increases the business property tax rates and decreases the tax rates on residents. We test this result using a French reform which changed the composition of the main local business tax base in 2010. Difference-in-difference estimations show that in 2010, the reduction in tax base mobility indeed resulted in a 14% rise in business property tax rates and a reduction in housing tax rates of 1.3%, compared to pre-reform average levels.
“Sub-metropolitan tax competition with mobile household and capital”, T. Ly, International Tax and Public Finance, 2018.
Working Paper available as : GATE Working Paper
Sub-metropolitan tax competition with mobile household and capital
Abstract
This paper investigates the efficiency properties of tax competition between submetropolitan jurisdictions when capital, residents and workers are mobile, and both households and firms compete for local land markets. We analyze two decentralized equilibria: (1) with a local tax on residents and two separate local taxes on capital and land inputs, efficiency is achieved and the existence of a marginal fiscal cost due to residents’ mobility is revealed; (2) combination of the taxes on capital and land inputs into a single business property tax leads local authorities to charge inefficiently high taxation on capital. We show that capital mobility induces a reduction in the business land taxation and local public inputs are used to offset the distorting effects of the property tax, accounting for the distorting impact of workers’ mobility.
Working papers
Taxes, traffic jam and splillover in the metropolis
Abstract
This paper studies local governments’ public policies in a metropolitan area plagued by traffic congestion, where both residents and workers consume local public goods.
We develop a new spatial sub-metropolitan tax competition model which features a central city surrounded by suburban towns linked by mobile capital and mobile residents who commute to work.
We show that Pareto-efficiency is achieved if towns can retain their workers using labor subsidies.
Otherwise, traffic congestion in the city is inefficiently high and local governments respond by setting inefficient public policies:
(1) the city over-taxes capital and under-taxes residents, which leads to too little capital and too many residents in the city;
(2) local public goods are under-provided in the city and over-provided in the towns.
“Fourniture de biens publics en présence de préférences altruistes : une approche redistributive avec sélection adverse“, T. Ly, HAL., 2014
Fourniture de biens publics en présence de préférences altruistes : une approche redistributive avec sélection adverse
Abstract
Cette étude porte un nouvel éclairage sur la fourniture d’un bien par une autorité publique à des agents ayant des préférences altruistes. Elle repose sur une généralisation du modèle de Besley et Coate (2002). Il y est montré que lorsque le niveau d’altruisme relatif est une information privée des agents, une interprétation de ce paramètre plus précise que celle qui en est communément faite doit être effectuée. L’altruisme relatif mesure la manière dont un agent perçoit sa situation relativement à celle d’autrui. Ainsi, afin de pallier son manque d’information, le gouvernement doit favoriser d’autant plus un agent qu’il a un niveau d’altruisme éloigné du niveau moyen. Il est également montré que lorsque le régulateur n’observe pas le type des agents, il est contraint à un arbitrage entre équité et efficacité. Sa règle de provision optimale doit donc tenir compte non seulement des préférences des agents mais également des inégalités que cette politique peut générer.
Work in progress
“Can private schools slow down the capitalization of public school quality into house values ? Evidence from Shanghai”, T. Ly, T. Wang, C. Zhan, Z. Zhao
Can private schools slow down the capitalization of public school quality into house values ? Evidence from Shanghai
Abstract
This paper uses a geographic regression discontinuity design to estimate the effect of private schools on supply efficiency and equality of elementary education supply. The study finds that private schools improve the spatial supply efficiency of elementary education significantly and reduce education inequality. The results show that private schools can markedly slow down the capitalization of public school quality into house values by 2.4 percent. This study provides an important basis for evaluating the role of social capital in elementary education. It also provides a new clue to optimize spatial allocation of elementary education resources in order to curb an overheated housing prices in specific regions.
“Housing prices, ownership incentives and rent control: Evidence from France”, S. Chareyron, T.Ly, Y. Trouvé-Sargison
Housing prices, ownership incentives and rent control: Evidence from France
Abstract
This paper studies the relevance of ownership incentives to improve housing affordability in a metropolitan area where rent control is imposed.
We develop a theoretical model in which owners of new housing benefit from either a homeownership incentive or a rental investment incentive.
We show that both incentives reduce second-hand housing prices and increase new housing prices.
Moreover, in the new housing market, rent control amplifies the price increase induced by both incentives.
However, in the second-hand housing market, while rent control amplifies the price decrease due to the homeownership incentive markets, it dampens the price cut due to the rental investment incentive.
We empirically test these findings by exploiting a 2014 French reform in the metropolitan area of Lyon which intensified both incentives.
We find that the reform reduces second-hand housing prices but increases new housing prices and that rent control amplifies the increase in the new housing prices but dampens the decrease in the second-hand housing prices which suggests that the effect of the rental investment incentive prevailed over that of the homeownership incentive.
Project
“Sorting, tax competition and the rise of local tax heavens”, T. Ly, R. Parchet
Awards
- Graduate Student Paper Award of the North American Regional Science Council (NARSC), 2019
→ Awarded to: “Taxes, traffic jam and spillover in the metropolis“
- PhD Prize of the French Economic Association (AFSE), 2019
→ Awarded to: “Tax competition within metropolitan areas“

The 2019 AFSE PhD Prize has been awarded to Tidiane Ly for his thesis entitled “Tax competition within Metropolitan areas”, conducted at the University of Lyon 2 under the supervision of Florence Goffette-Nagot and Sonia Paty. The jury was really impressed by the originality, the quality and the rigor of the work carried out. The jury also greatly appreciated Tidiane’s wish to provide policy recommendations from his theoretical investigations and findings. Indeed, his thesis helps municipalities and lower-level jurisdictions in their policy instrument choice, and suggests that reforming the local institutional context requires to account for the specific responses of local governments.
Conferences & Presentations
- Annual Meeting of the National Tax Association (NTA), november 2019, Tampa
- Annual Meeting of the North American Regional Science Council (NARSC), november 2019, Pittsburgh
- Invited Seminar Cesaer, INRA october 2019, Dijon
- Annual Meeting of the French Economic Association (AFSE), june 2019, Orléans
- Workshop on economics of taxation and public expenditures, june 2019, Barcelona
- Swiss workshop on local public finance and regional economics, may 2019, Lugano
- Invited Seminar Università della Svizzera italiana, november 2018, Lugano
- Public Economics at the Regional Level (PEARL) workshop, september 2018, Zermatt
- European Public Choice Society conference, april 2018, Roma
- Invited Seminar Economics and Taxation Group, Panthéon ASSAS, december 2017, Paris
- Workshop Public Policies, Cities and Regions, december, 2017, Lyon
- Public Policies and Spatial Economics Seminar, october 2017, Lyon
- Rhône Spatial Economics Workshop, march 2017, Geneva
- Annual Meeting of the Urban Economics Association (UEA), november 2016, Minneapolis
- Public Policies and Spatial Economics Seminar, october 2016, Lyon
- Public Economics at the Regional Level (PEARL) workshop, september 2016, Santiago de Compostela
- Annual Meeting of the French Economic Association (AFSE), june 2016, Nancy
- Journées de Microéconomie Appliquée (JMA), june 2016, Besançon
- Workshop Political Economy and Local Public Finance, september 2015, Lille
- GATE Research Seminar, october 2015, Lyon
- Public Policies and Spatial Economics Seminar, may 2015, Lyon
- GATE Seminar, december 2014, Lyon