Back to questioning the Muon2 rules

[Torie]

I drew this Pub gerrymander circa after the 2020 census for the benefit of Krazen, to display to him the joys of at once legal yet aesthetic Pub gerrymanders (yes, I know I was soft in Pubbing up MI-03 (shifting a bit of Pub strength into MI-03 from MI-02), but my heart just wasn't in it to squeeze out another Pub point or two, at the cost of just going slash and burn), and it raised an issue that we have discussed before. Below is my macro-chop into Macomb. I take it I could avoid two erosity penalty points by avoiding having the chop into Macomb result in a CD line touching either Centerline or Roseville. Is that wise? Remind me what the policy reason here is again. By avoiding the touchings, the lines would become more jagged (it would look like a staircase), leaving the "artist" community very upset at the discretion of it all. We strive for straight lines, unless the cost is too high in the gerrymander mode, not jagged ones.



Feel free to move this post elsewhere, and delete this thread if you like, Muon2. I am just too lazy to search for the old thread that included our discussions. No doubt you know exactly where it is!

[Torie]

You have macrochopped Warren and the erosity is much higher than you think. Once it is macrochopped we consider the subunits of the macrochop. In this case it would be the precincts within Warren. The erosity just across the two parts of Warren is something like 13 or 14 given the number of precincts that are connected by road there. If you try to avoid touching Center Line it will only make the erosity that much worse through the very stair steps you describe.

As I look at it, the line across Warren isn't that straight. The better plan would fill that last precinct surrounding Center Line with blue Warren, then shift the northwest blue precinct over to pink Warren. Still both are gross compared to any plan that keeps Warren whole or at least to a simple chop.

You do it precinct by precinct? That seems insane to me (ask me if you want, as to why). I thought it was by subunit by subunit, which makes more sense, putting aside the issue that I raised. It is not easy to do a simple chop of Warren. But yeah, it could be better, if not in the gerrymandering mode, when it comes to straight lines probably.

I guess the real issue is the zoom within zoom. First you zoom into a macro chopped county, and then you zoom within a macro chopped subunit (this time precinct by precinct). I never understood that before. Maybe that has merit. Is that in your rules? If so, is the double zoom clearly stated? 

The result is that one would never unless one has to, macro-chop a subunit. Maybe given that Warren does not have hoods (ala Detroit), you are just reverting to precincts. That seems problematical. When does a subunit get large enough, that you search for hoods, and if you find none, revert to precincts?

[Torie]

Is that all clearly stated in your rules? Using precincts I think is a terrible idea. They are too small among other things. And they are subject to arbitrary adjustment to affect the score. For example, knowing the Muon2 rules, as a Pub gerrymanderer, I would call up the Pub hack who runs the Board of Elections in Warren, and tell him to redraw the precinct lines as follows (each square is a precinct, with the CD border running between two precincts that stretch the length of the city of Warren):



Warren does I see have school districts in which the precincts conveniently enough seem to be nested, so I guess those could be used.

I see that the precinct lines have changed since 2008, but an approximation of school district nesting would look like the below. It isn’t very pretty, because the school district lines are not pretty.  



Of course, one can lose the subunit macro-chop by doing the below.  But then, if one is in the gerrymandering mode, one isn’t playing by the Muon2 rules anyway. Perhaps there should be chapter on the Muon2 rules for gerrymanders, which penalizes macro-chops. Putting aside the Warren contretemps, notice that my map avoids macro-chops, except where absolutely necessary to get the job done (i.e., Ingram).  That is not an accident, but I digress.  

[Torie]

A macro chop is 38k+. 

"If you want to avoid the macrochop (35K and up) why not put Warren and Center Line in the blue CD minus a nice rectangular chop out of the NE corner of Warren for the pink?"

Because Eastpointe is where the Dems are in highest concentration (this map is designed to be a "good government" gerrymander, following the pigs get fat, but hogs get slaughtered metric), and also the blacks for VRA purposes (with southern Warren next best). The two black CD's are on the cusp. The one going into Oakland is 49.9% BVAP, and the cyan one going into Macomb is 51% BVAP. That is based on the 2010 census. I suspect the percentages are lower now (and the map assumed the population changes were even across the counties, and they certainly are not in Wayne, Macomb or Oakland, so the cyan CD will need to dig deeper into Macomb anyway, and ditto for the black CD having to go deeper into Oakland. That will reduce the black percentages too.

[Torie]

Yes, I know, a lower percentage might well be legal. But politics is so racially polarized, particularly in Macomb, that the BVAP cannot go too much below 50% without it being problematical (bearing in mind that there are few Hispanics to push the CBVAP up). I suspect that in 2021 or 2022, when the lines are drawn, we might be down to about 45% BVAP for both CD's, if the BVAP is evenly split between them.