Tasos Kalandrakis

Dynamic Legislative Policy Making

We prove existence of stationary Markov perfect equilibria in an infinite-horizon model of legislative policy making in which the policy outcome in one period determines the status quo for the next. We allow for a multidimensional policy space and arbitrary smooth stage utilities, and we assume preferences and the status quo are subject to arbitrarily small shocks. We prove that equilibrium continuation values are differentiable and that proposal strategies are continuous almost everywhere. We establish upper hemicontinuity of the equilibrium correspondence, and we provide weak conditions under which each equilibrium of our model determines an aperiodic transition probability over policies. We establish a convergence theorem giving conditions under which the invariant distributions generated by stationary equilibria must be close to the core in a canonical spatial model. Finally, we extend the analysis to sequential move stochastic games and to a version of the model in which the proposer and voting rule are determined by play of a finite, perfect information game.

A Newton collocation method for solving dynamic bargaining games

We develop and implement a collocation method to solve for an equilibrium in the dynamic legislative bargaining game of Duggan and Kalandrakis 2008, unpublished manuscript. We formulate the collocation equations in a quasi-discrete version of the model, and we show that they are locally Lipchitz continuous and directionally differentiable. In numerical experiments, we successfully implement a globally convergent variant of Broyden’s method on a preconditioned version of the collocation equations, and the method economizes on computation cost by more than 50% compared to the value iteration method. We rely on a continuity property of the equilibrium set to obtain increasingly precise approximations of solutions to the continuum model. We showcase these techniques with an illustration of the dynamic core convergence theorem of Duggan and Kalandrakis 2008, unpublished manuscript in a nine-player, two-dimensional model with negative quadratic preferences.

Dynamics of the presidential veto: A computational analysis

We specify and compute equilibria of a dynamic policy-making game between a president and a legislature under institutional rules that emulate those of the US Constitution. Policies are assumed to lie in a two-dimensional space in which one issue dimension captures systemic differences in partisan preferences, while the other summarizes non-partisan attributes of policy. In any period, the policy choices of politicians are influenced by the position of the status quo policy in this space, with the current policy outcome determining the location of the status quo in the next period. Partisan control of the legislature and presidency changes probabilistically over time. We find that politicians strategically compromise their ideal policy in equilibrium, and that the degree of compromise increases when the opposition party is more likely to take control of the legislature in the next period, while politicians become relatively more extreme when the opposition party is more likely to control the presidency. We measure gridlock by (the inverse of) the expected distance of enacted policies from the status quo in the long run, and we show that both gridlock and the long run welfare of a representative voter are maximized when government is divided without a supermajority in the legislature. Under unified government, we find that the endogeneity of the status quo leads to a non-monotonic effect of the size of the legislative majority on gridlock; surprisingly, under unified government, gridlock is higher when the party in control of the legislature has a supermajority than when it has a bare majority. Furthermore, a relatively larger component of policy change occurs in the non-partisan policy dimension when a supermajority controls the legislature. We conduct constitutional experiments, and we find that voter welfare is minimized when the veto override provision is abolished and maximized when the presidential veto is abolished.

A Reputational Theory of Two-Party Competition

I study a dynamic game of two-party competition in which party preferences are private information, exhibit serial correlation, and change with higher probability following defeat in elections. Assuming partisans care sufficiently about office, extreme policies are pursued with positive probability by the government when (a) both parties have a reputation for being extreme that exceeds a fixed level, and (b) elections are close in that both parties have similar reputations. Two qualitatively different equilibrium dynamics are possible depending on the speed with which the latent preferences of parties in government shift between moderation and extremism relative to the opposition. One dynamic produces regular government turnover and extreme policies along the path of play, whereas the other involves a strong incumbency advantage and moderate policies.

On participation games with complete information

We analyze a class of two-candidate voter participation games under complete information that encompasses as special cases certain public good provision games. We characterize the Nash equilibria of these games as stationary points of a non-linear programming problem, the objective function of which is a Morse function (onethat does not admit degenerate critical points) for almost all costs of participation. We use this fact to establish that, outside a closed set of measure zero of participation costs, all equilibria of these games are regular (an alternative to the result of De Sinopoli and Iannantuoni in Econ Theory 25(2):477–486, 2005). One consequence of regularity is that the equilibria of these games are robust to the introduction of (mild) incomplete information. Finally, we establish the existence of monotone Nash equilibria, such that players with higher participation cost abstain with (weakly) higher probability.

Pareto efficiency in the dynamic one-dimensional bargaining model

Pareto-dominated agreements are shown to prevail with positive probability in an open set of status quo in a Markov perfect equilibrium of a one-dimensional dynamic bargaining game. This equilibrium is continuous, symmetric, with dynamic preferences that satisfy the single-plateau property. It is also shown that there does not exist a symmetric equilibrium with single-peaked preferences.

Computation of equilibrium values in the Baron and Ferejohn bargaining model

Computation of exact equilibrium values for n-player divide-the-dollar legislative bargaining games as in Baron and Ferejohn (1989) with general quota voting rules, recognition probabilities, and discount factors, can be achieved by solving at most n bivariate square linear systems of equations. The approach recovers Eraslans (2002) uniqueness result and relies on a characterization of equilibria in terms of two variables that satisfy a pair of piecewise linear equations.