can garner enough votes in the next election to remain in government.Since votes can only plausibly be instrumental goals,for parties in government,seeking to implement their ideal policies will most likely be the most important concern of the parties.Another support for emphasizing parties'policy concern comes from the literature on partisan models of party competition.According to the partisan models,parties as well as voters care about policy outcomes in addition to winning elections(Calvert 1985;Wittman 1977, 1983),and rather than in a Downsian model where parties choose policies in order to win elections,"parties want to be elected in order to choose policies".3 A unified and cohesive party or governing coalition tend to have an advantage in decision-making over an internally divided or heterogeneous party or coalition;such an advantage is more pronounced when the party is in the government trying to implement its preferred policies.Intuitively,heterogeneity adds a number of veto players to the decision-making process,and as the number of veto players increases,the probability of making policy changes decreases (Axelrod and Keohane 1985;Tsebelis 2002).Higher cohesiveness among the constituency tends to decrease the number of the potential"veto players"as various segments now possess increasingly similar economic interests.To the extent that parties care about policy outcomes,they have an interest to have a cohesive constituency so as to decrease the number of potential veto players.The following model shows how interindustry labor mobility is intrinsically linked with the cohesiveness among the constituencies of different political spectrum. 2.2.A simple general equilibrium model on constituency cohesiveness Ronald Jones proposed a general equilibrium model of production that analyzes an economy consisting of two factors (Labor and Capital),two sectors,and two 3 Alesina and Rosenthal,1995,p17.can garner enough votes in the next election to remain in government. Since votes can only plausibly be instrumental goals, for parties in government, seeking to implement their ideal policies will most likely be the most important concern of the parties. Another support for emphasizing parties’ policy concern comes from the literature on partisan models of party competition. According to the partisan models, parties as well as voters care about policy outcomes in addition to winning elections (Calvert 1985; Wittman 1977, 1983), and rather than in a Downsian model where parties choose policies in order to win elections, “parties want to be elected in order to choose policies”. 3 A unified and cohesive party or governing coalition tend to have an advantage in decision-making over an internally divided or heterogeneous party or coalition; such an advantage is more pronounced when the party is in the government trying to implement its preferred policies. Intuitively, heterogeneity adds a number of veto players to the decision-making process, and as the number of veto players increases, the probability of making policy changes decreases (Axelrod and Keohane 1985; Tsebelis 2002). Higher cohesiveness among the constituency tends to decrease the number of the potential “veto players” as various segments now possess increasingly similar economic interests. To the extent that parties care about policy outcomes, they have an interest to have a cohesive constituency so as to decrease the number of potential veto players. The following model shows how interindustry labor mobility is intrinsically linked with the cohesiveness among the constituencies of different political spectrum. 2.2. A simple general equilibrium model on constituency cohesiveness Ronald Jones proposed a general equilibrium model of production that analyzes an economy consisting of two factors (Labor and Capital), two sectors, and two 3 Alesina and Rosenthal, 1995, p17