Changes

In first stage we vote on <math>x_{i}</math>. and obtain policy equal to median voters bliss point <math>x_{m}</math>. In second stage we vote on <math>y_i</math> and obtain policy equal to median voters bliss point <math>y_m</math>, so we obtain unique outcome <math>z=(x_m, y_m)</math>. Notice, that with this sequential voting, we do not get the median policy, but the median policy by dimension.