ND Nicolas Djob
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Research

Working papers and ongoing research

My research investigates tax design, imperfect competition, firm mobility, market power, and income distribution in integrated economies.

Research output

Working Papers

Completed research papers currently available for circulation.

Fiscal Union Without Factor Union: Optimal VAT under Monopolistic Competition

Nicolas Djob Li Ngue Bikob · 2026 · Under review International Tax and Public Finance

Under review

This paper studies destination-based value-added taxation in a two-country economy with monopolistic competition, endogenous entry, and asymmetric public-expenditure requirements. A supranational planner can accommodate international imbalances through a zero-sum transfer, creating a common marginal cost of public funds. The optimal Ramsey rule combines social resource costs, consumption values, product-market competition, and entry responses.

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BibTeX 
@unpublished{djob2026allocation,
  author = {Djob Li Ngue Bikob, Nicolas},
  title  = {Fiscal Union Without Factor Union: Optimal VAT under Monopolistic Competition},
  year   = {2026},
  note   = {Working paper}
}

Commodity Tax Principles, Firm Location, and Skilled-Wage Incidence under the Destination and Origin Principles

Nicolas Djob Li Ngue Bikob · 2026 · Revised and Resubmit at International Tax and Public Finance

Revised and Resubmit · 2026

The paper compares destination- and origin-based commodity taxation in an economy with monopolistic competition, mobile firms, and heterogeneous labour. Destination taxation changes consumer prices but leaves production location pinned down by factor supplies. Origin taxation changes the relative attractiveness of locations and therefore affects skilled wages, capital income, consumer prices, and fiscal revenue through firm relocation.

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BibTeX 
@unpublished{djob2026principles,
  author = {Djob Li Ngue Bikob, Nicolas},
  title  = {Commodity Tax Principles, Firm Location, and Skilled-Wage Incidence under the Destination and Origin Principles},
  year   = {2026},
  note   = {Submitted to International Tax and Public Finance}
}

Monopolistic Competition in OLG models: efficiency and inequality

Nicolas Djob Li Ngue Bikob and Pascal Belan · 2026 · Submitted to Journal of Public Economic Theory

Submitted · 2026

We study intergenerational and intragenerational redistribution in an overlapping-generations economy with monopolistic competition, in which workers differ in skill and firms pay a fixed entry cost in physical capital. This capital-based fixed cost implies that greater market power raises the equilibrium real interest rate by lowering wages and aggregate saving. We characterize Pareto-efficient steady states and show that productive and dynamic efficiency require correcting the markup distortion and attaining the Golden Rule. Because skill is unobservable, however, the available fiscal instruments cannot in general decentralize an arbitrary distribution along the Pareto frontier, and financing the Pigouvian subsidy may widen wage and consumption inequality. At the second best, the capital correction remains efficient. With homogeneous time preferences, this implies the Golden Rule and leaves labor taxation as the main intragenerational redistributive instrument. With heterogeneous patience, capital policy acquires a redistributive role and the optimal allocation may depart from the Golden Rule.

BibTeX 
@unpublished{djob2026principles,
  author = {Djob Li Ngue Bikob, Nicolas and Belan, Pascal},
  title  = {Monopolistic Competition in OLG Models: Efficiency and
                  Inequality},
  year   = {2026},
  note   = {Submitted to Journal of Public Economic Theory}
}

Research agenda

Ongoing Research

Research projects currently under development. Drafts are available upon request.

Origin vs Destination-Based Commodity Taxation with Skilled Labor Mobility

with Thierry Noumi · 2026 · Ongoing research

Optimal Taxation and Firms spatial location

Draft available upon request
BibTeX 
@unpublished{belan_djob2026olg,
  author = { Thierry Nana Noumi and Nicolas Djob Li Ngue},
  title  = {Origin vs Destination-Based Commodity Taxation with Skilled Labor Mobility},
  year   = {2026},
  note   = {Ongoing research}
}

Commodity Tax Principles, Iceberg Trade Costs, and Skilled-Wage Incidence

Anderson Vil, Nicolas Djob Li Ngue Bikob and Usama Jamal · 2026 · Ongoing research

International taxation

This project studies the design and incidence of commodity taxation under the destination and origin principles when international trade is subject to iceberg costs. The analysis examines how trade frictions affect firms’ location decisions, cross-border tax competition, consumer prices, and skilled wages. Particular attention is paid to the interaction between commodity-tax rules, market access, production relocation, and the distribution of welfare between skilled workers, unskilled workers, consumers, and governments.

Draft available upon request
BibTeX 
@unpublished{vil_djob_jamal2026tax,
  author = {Vil, Anderson and Djob Li Ngue Bikob, Nicolas and Jamal, Usama},
  title  = {Commodity Tax Principles, Iceberg Trade Costs, and Skilled-Wage Incidence},
  year   = {2026},
  note   = {Ongoing research}
}

Dissertation

PhD Thesis

Taxation in a Globalized Economy: Resource Allocation, Monopolistic Competition, and Cross-Border Dynamics

Nicolas Djob Li Ngue Bikob · CY Cergy Paris Université · 2025

PhD thesis

The dissertation studies tax-policy design in a globalized economy. Its chapters examine optimal destination-based VAT, the welfare comparison between destination and origin principles, and extensions involving trade costs and the mobility of skilled labour.

BibTeX 
@phdthesis{djob2025thesis,
  author = {Djob Li Ngue Bikob, Nicolas},
  title  = {Taxation in a Globalized Economy: Resource Allocation, Monopolistic Competition, and Cross-Border Dynamics},
  school = {CY Cergy Paris Université},
  year   = {2025}
}