Doctorant F/H A learning theory for over-parametrized bilevel optimization

Contract type : Fixed-term contract

Level of qualifications required : Graduate degree or equivalent

Fonction : PhD Position

About the research centre or Inria department

The Inria Grenoble research center groups together almost 600 people in 23 research teams and 7 research support departments.

Staff is present on three campuses in Grenoble, in close collaboration with other research and higher education institutions (University Grenoble Alpes, CNRS, CEA, INRAE, …), but also with key economic players in the area.

Inria Grenoble is active in the fields of high-performance computing, verification and embedded systems, modeling of the environment at multiple levels, and data science and artificial intelligence. The center is a top-level scientific institute with an extensive network of international collaborations in Europe and the rest of the world.

Context

Bilevel optimization is a class of methods for solving optimization problems that have a hierarchical struc- ture. These problems typically require optimizing two interdependent objectives: a lower-level objective g whose optimal solution is provided to an upper-level objective f. The hierarchical structure arises by taking into account the dependence of the lower-level solution on the upper-level variable (see figure below). These methods are increasingly recognized as a promising approach for solving a multitude of machine learning problems such as hyper-parameter optimization, meta-learning, meta-reinforcement learning [1] and metric learning [2]. Consequently, there has been an increased interest in developing scalable and reliable bilevel optimization methods for machine learning [3].

Despite recent progress in bilevel optimization, the hierarchical structure of bilevel problems raises many challenges when applied to machine learning problems involving large over-parametrized neural networks. While the use of such networks is ubiquitous and offers high modelling flexibility, it often results in non-convex bilevel problems with multiple solutions for which the generalization properties are poorly understood.

The PhD project aims at developing a learning theory for predictive models resulting from a bilevel optimization procedure.

Assignment

Assignments :
The PhD project aims at developing a learning theory for predictive models resulting from a bilevel optimization procedure.

 

Main activities

Research

Benefits package

  • Subsidized meals
  • Partial reimbursement of public transport costs
  • Leave: 7 weeks of annual leave + 10 extra days off due to RTT (statutory reduction in working hours) + possibility of exceptional leave (sick children, moving home, etc.)
  • Possibility of teleworking (90 days / year) and flexible organization of working hours
  • Professional equipment available (videoconferencing, loan of computer equipment, etc.)
  • Social, cultural and sports events and activities
  • Access to vocational training
  • Complementary health insurance under conditions

Remuneration

1st and 2nd year: 2 082 euros gross salary /month

3rd year: 2 190 euros gross salary / month