Fair redistricting is hard

Gerrymandering is a long-standing issue within the U.S. political system, and it has received scrutiny recently by the U.S. Supreme Court. In this note, we prove that deciding whether there exists a fair redistricting among legal maps is NP-hard. To make this precise, we use simplified notions of "legal" and "fair" that account for desirable traits such as geographic compactness of districts and sufficient representation of voters. The proof of our result is inspired by the work of Mahanjan, Minbhorkar and Varadarajan that proves that planar k-means is NP-hard

Don’t Just Make Redistricters More Accountable to the People, Make Them the People

This thesis investigated the heat transfer of internally oil cooled rotors in permanent magnet electric machines which are, among other things, used in hybrid vehicles or zero emission vehicles. The magnets become sensitive and can be demagnetized at high working temperatures, hence the need of cooling. The scope of this work included CFD simulations in STAR-CCM+. Three different 3D multiphase models simulating the oil propagation in the rotor were performed. A Lagrangian multiphase model combined with a fluid film model was the most suitable model for simulating the spray of the oil and the film thickness along the inner rotor wall. It was noticed that periodic boundaries caused problems for the fluid film model, therefore a complete geometry was preferred over a truncated model. The 3D solutions provided thicker film thicknesses than the analytical solutions from the fluid film thickness theory. The maximum analytical thickness was of the same order of magnitude as the surface average film thickness provided by the multiphase models. This thickness was assumed to be constant when used as the base for the fluid region in the 2D one-phase models.The study showed that aluminum was the most suitable rotor material due to its high conductive capacity, which provided a more even distribution of the temperature in the solid and hence resulted in lower overall temperatures. The cooling power increased linearly with the volumetric flow rate, however the heat transfer coefficient decreased for the higher flow rates. A volumetric flow rate of 10dl/min was recommended. A 2D model was compared to a preliminary experiment and showed that these were not correlated. The conclusion was that more experiments and simulations are needed in order to confirm the validity of the 2D model

A Citizen's Guide to Redistricting

Provides a detailed overview of states' rules and processes for redrawing federal, state, and local legislative districts. Illustrates possible motives behind redistricting, effects on elections, implications for legislation, and reform recommendations

The “Unwelcome Obligation”: Why Neither State nor Federal Courts Should Draw District Lines

In recent years, the judiciary’s inability to hold state legislatures accountable for partisan gerrymanders has encouraged state governments to draw legislative and congressional district lines with high partisan advantage, thereby allowing a political party to acquire seats in numbers disproportionate to their popular support. In 2017, the U.S. Supreme Court granted certiorari on two partisan gerrymandering cases: Gill v. Whitford and Benisek v. Lamone. Although the Court might articulate a judicially manageable standard to determine when a districting plan is politically fair, other methods to prevent federal courts from creating district maps that perpetuate partisan bias exist. This Note examines and critiques current debates regarding the judiciary’s role in redistricting and adjudicating partisan gerrymandering claims. It argues that independent redistricting commissions—enacted through state voter initiatives or referendums—should replace federal courts’ authority to develop redistricting plans

Getting From Here to There in Resistricting Reform

This symposium has been largely devoted to whether and how we ought to reform our districting process. Today I want to talk about a related but often neglected question: if we are serious about reform, how do we make it happen? I will thus set aside some of the important normative and practical questions associated with what kind of redistricting reform we should pursue and focus instead on how to get from here to there. As we think about getting redistricting reform passed, we ought to ask ourselves three questions. First, what should our goals be during the 2010 cycle? Second, moving from principle to practice, what specifically can we do to promote reform during this period? Third, if we succeed in getting some traction with reform post-2010, what kind of reform proposals should we push