Valeriya V. Lakshina National Research University Higher School of Economics   Bolshaya Pecherskaya St., 25/12, room 411 Nizhny Novgorod, 603155 Russia   vlakshina@hse.ru   https://www.hse.ru/en/staff/lakshinav           JEL Areas: C2 : Single Equation Models; Single Variables: General C3 : Multiple or Simultaneous Equation Models: General