How to Learn to Defeat Noisy Robot in Rock-Paper-Scissors Game: An Exploratory Study
This paper studies learning in strategic environment using experimental data from the Rock-Paper-Scissors game. In a repeated game framework, we explore the response of human subjects to uncertain behavior of strategically sophisticated opponent. We model this opponent as a robot who played a stationary strategy with superimposed noise varying across four experimental treatments. Using experimental data from 85 subjects playing against such a stationary robot for 100 periods, we show that humans can decode their strategies, on average outperforming the random response to such a robot by 17%. Further, we show that human ability to recognize such strategies decreases with exogenous noise in the behavior of the robot. Further, we fit learning data to classical Reinforcement Learning (RL) and Fictitious Play (FP) models and show that the classic action-based approach to learning is inferior to the strategy-based one. Unlike the previous papers in this field, e.g. Ioannou, Romero (2014), we extend and adapt the strategy-based learning techniques to the 3x3 game. We also show, using a combination of experimental and ex-post survey data, that human participants are better at learning separate components of an opponent's strategy than in recognizing this strategy as a whole. This decomposition offers them a shorter and more intuitive way to figure out their own best response. We build a strategic extension of the classical learning models accounting for these behavioral phenomena.
Using a simplified multistage bidding model with asymmetrically informed agents, De Meyer and Saley  demonstrated an idea of endogenous origin of the Brownian component in the evolution of prices on stock markets: random price fluctuations may be caused by strategic randomization of “insiders.” The model is reduced to a repeated game with incomplete information. This paper presents a survey of numerous researches inspired by the pioneering publication of De Meyer and Saley.
This paper presents a novel combinatorial approach for voting rule analysis. Applying reversal symmetry, we introduce a new class of preference profiles and a new representation (bracelet representation) of preference profiles. By applying an impartial, anonymous, and neutral culture model for the case of three alternatives, we obtain precise theoretical values for the number of election scores for the plurality rule, the Kemeny rule, the Borda rule, and the scoring rules in the extreme case.
This paper evaluates the empirical performance of a medium-scale DSGE model with agents forming expectations using small forecasting models updated by the Kalman filter. The adaptive learning model fits the data better than the rational expectations (RE) model. Beliefs about the inflation persistence explain the observed decline in the mean and the volatility of inflation as well as Phillips curve flattening. Learning about inflation results in lower estimates for the persistence of the exogenous shocks that drive price and wage dynamics in the RE version of the model. Expectations based on small forecasting models are closely related to the survey evidence on inflation expectations.
In this paper, we investigate real-time behavior of constant-gain stochastic gradient (SG) learning, using the Phelps model of monetary policy as a testing ground. We find that whereas the self-confirming equilibrium is stable under the mean dynamics in a very large region, real-time learning diverges for all but the very smallest gain values. We employ a stochastic Lyapunov function approach to demonstrate that the SG mean dynamics is easily destabilized by the noise associated with real-time learning, because its Jacobian contains stable but very small eigenvalues. We also express caution on usage of perpetual learning algorithms with such small eigenvalues, as the real-time dynamics might diverge from the equilibrium that is stable under the mean dynamics.
The paper examines the structure, governance, and balance sheets of state-controlled banks in Russia, which accounted for over 55 percent of the total assets in the country's banking system in early 2012. The author offers a credible estimate of the size of the country's state banking sector by including banks that are indirectly owned by public organizations. Contrary to some predictions based on the theoretical literature on economic transition, he explains the relatively high profitability and efficiency of Russian state-controlled banks by pointing to their competitive position in such functions as acquisition and disposal of assets on behalf of the government. Also suggested in the paper is a different way of looking at market concentration in Russia (by consolidating the market shares of core state-controlled banks), which produces a picture of a more concentrated market than officially reported. Lastly, one of the author's interesting conclusions is that China provides a better benchmark than the formerly centrally planned economies of Central and Eastern Europe by which to assess the viability of state ownership of banks in Russia and to evaluate the country's banking sector.
The paper examines the principles for the supervision of financial conglomerates proposed by BCBS in the consultative document published in December 2011. Moreover, the article proposes a number of suggestions worked out by the authors within the HSE research team.