Electing a parliament

We present a model where a society elects a parliament by voting for candidates belonging to two parties. The electoral rule determines the seats distribution between the two parties. We analyze two electoral rules, multidistrict majority and single-district proportional. In this framework, the policy outcome is simply a function of the number of seats parties take in the election. We prove that in both systems there is a unique pure strategy perfect equilibrium outcome. Finally, we compare the outcomes in the two systems

Electing a parliament

We present a model where a society elects a parliament by voting for candidates belonging to two parties. The electoral rule determines the seats distribution between the two parties. We analyze two electoral rules, multidistrict majority and single-district proportional. In this framework, the policy outcome is simply a function of the number of seats parties take in the election. We prove that in both systems there is a unique pure strategy perfect equilibrium outcome. Finally, we compare the outcomes in the two systems.

The effect of ideology on policy outcomes in proportional representation systems

In this paper we propose a model in which there are ideological and strate- gic voters who vote under poportional rule. We prove that the behavior of ideological voters matters for the determination of the outcome. We show that a subset of strategic voters partially counteracts the votes of the ideological voters.Proportional Election, Strategic Voting, Ideological Voting

Moderating Government

We consider a model where policy motivated citizens vote in two simultaneous elections, one for the President who is elected by majority rule, in a single national district, and one for the Congressmen, each of whom is elected by majority rule in a local district. The policy to be implemented depends not only on who is elected President but also on the composition of the Congress. We characterize the equilibria of the model using a conditional sincerity concept that takes into account the possibility that some voters may be simultaneously decisive in both elections. Such a concept emerges naturally in a model with trembles. A crucial feature of the solution is the moderation of Government.voting, proportional rule, majority, parliament.

Changes in total choline concentration in the breast of healthy fertile young women in relation to menstrual cycle or use of oral contraceptives: a 3-T 1H-MRS study

BACKGROUND: To evaluate changes in total choline (tCho) absolute concentration ([tCho]) in the breast of healthy fertile women in relation to menstrual cycle (MC) or use of oral contraceptives (OC). METHODS: After institutional review board approval, we prospectively evaluated 40 healthy fertile volunteers: 20 with physiological MC, aged 28 ± 3 years (mean ± standard deviation; nOC group); 20 using OC, aged 26 ± 3 years (OC group). Hormonal assays and water-suppressed single-voxel 3-T proton magnetic resonance spectroscopy (1H-MRS) were performed on MC days 7, 14, and 21 in the nOC group and only on MC day 14 in the OC group. [tCho] was measured versus an external phantom. Mann-Whitney U test and Spearman coefficient were used; data are given as median and interquartile interval. RESULTS: All spectra had good quality. In the nOC group, [tCho] (mM) did not change significantly during MC: 0.8 (0.3-2.4) on day 7, 0.9 (0.4-1.2) on day 14, and 0.4 (0.2-0.8) on day 21 (p = 0.963). In the OC group, [tCho] was 0.7 (0.2-1.7) mM. The between-groups difference was not significant on all days (p ≥ 0.411). All hormones except prolactin changed during MC (p ≤ 0.024). In the OC group, [tCho] showed a borderline correlation with estradiol (r = 0.458, p = 0.056), but no correlation with other hormones (p ≥ 0.128). In the nOC group, [tCho] negatively correlated with prolactin (r = -0.587, p = 0.006) on day 7; positive correlation was found with estradiol on day 14 (r = 0.679, p = 0.001). CONCLUSIONS: A tCho peak can be detected in the normal mammary gland using 3-T 1H-MRS. The [tCho] in healthy volunteers was 0.4-0.9 mM, constant over the MC and independent of OC use

Extreme wave analysis based on atmospheric pattern classification: an application along the Italian coast

Abstract. This paper provides a methodology for classifying samples of significant wave-height peaks in homogeneous subsets in terms of the atmospheric circulation patterns behind the observed extreme wave conditions. Then, a methodology is given for the computation of the overall extreme value distribution by starting from the distributions fitted to each single subset. To this end, the k-means clustering technique is used to classify the shape of the wind fields that occurred simultaneously to and prior to the occurrences of the extreme wave events. This results in a small number of characteristic circulation patterns related to as many subsets of extreme wave values. After fitting an extreme value distribution to each subset, bootstrapping is used to reconstruct the omni-circulation pattern's extreme value distribution. The methodology is applied to several locations along the Italian buoy network, and it is concluded from the obtained results that it yields a two-fold advantage: first, it is capable of identifying clearly differentiated subsets driven by homogeneous circulation patterns; second, it allows one to estimate high-return-period quantiles consistent with those resulting from the usual extreme value analysis. In particular, the circulation patterns highlighted are analyzed in the context of the Mediterranean Sea's atmospheric climatology and are shown to be due to well-known cyclonic systems typically crossing the Mediterranean basin