Chops and Erosity - Great Lakes Style

[jimrtex]

Somehow I knew that is what you would do.  For erosity, would not a map with juts containing now much area, but a lot of population, garner far less of a penalty, as compared with what makes for the minimum line length of more rural districts large in area, unless you somehow take a ratio of line length to population for subsets of each CD? Your method really emphasizes overall equality in population. That will tend to result I suspect in "uglier" maps. Anyway, it will be interesting to compare what your map looks like that gets the high score with your system vis  a vis Mike's, and get forumite reaction to it. Good luck!

Can you give me a hypothetical example of the bolded part?  I'm not sure what you are saying.

[traininthedistance]

Train, do you think you did your best to minimize your intra Philly UCC erosity zoom score between CD's? It may be that the PA-08 jut into Philly is not a macrochop, which gives you a freebie, which is itself an issue in the scoring system (maybe all chops into a county except microchops, should be zoomed, but penalized only for the excess subunit connector cuts (Philly hoods in this case) over the minimum for the size of the chop), but I wonder about PA-07 going into Berks rather than Chester.  

The PA-8 part in Philly is a macrochop; no getting around the fact that PA-8 is Bucks plus a macrochop of something else.  The lines were drawn there to minimize chops rather than erosity, the wards are pretty large out in the far Northeast which decreases flexibility.  Presumably you could lower the erosity by chopping one of the big wards or something instead.

PA-7 doesn't go anywhere near Berks, that's the Delco district. Its chops are more erosity-minimizing, with the Chester and Philly bits non-macro, while the remainder of Montgomery that's too big for PA-13 is, yes, a macrochop, but a pretty obvious and clean one.

It is very likely that a different line between 1 and 2 could score better, but I wanted to keep the traditional Broad Street divide for the time being.  

[muon2]

To be connected, counties must be contiguous.   In general there must be a direct, non-circuitous way to travel between the counties, particularly considering the distribution of the population.  There is no requirement that the route be entirely in the two counties, but if the route goes through other counties it should not be through population concentrations, or drawn in a way to evade the population concentrations.

Can this be defined in a way that a person sitting at a computer with a program such as MapQuest could determine whether such a connection exists? As I read this it has a substantial subjective component, and two groups working on the connectivity map could reasonably come up with two different plans.

[jimrtex]

Scoring example:



This is a submitted map.  The three multi-county Urban County Clusters (UC), Detroit, Lansing, and Grand Rapids are highlighted in purple.

Each region is comprised of a group of connected counties, and has a population that is approximately equal to that of a whole number of congressional districts of ideal size.  For Michigan, the ideal population (the quota) is 705,974 which is the state's population of 9,883,640 divided by the total number of congressional districts (14). 

The population of each region is shown as the actual population relative to the quota.  For example, the population of the blue region in the Upper Peninsula and northern Lower Peninsula is 701,034, which is 0.993 (99.3%) of the quota.

An urban county cluster must be wholly contained in a region.  There may be multiple UCC in a region.   There are 11 single county UCC in Michigan (not shown).  In this submited plan, the Muskegon UCC is in the same region as the Grand Rapids UCC, and the Jackson UCC is in the same region as the Lansing UCC.

It is within the rules to have multiple larger UCC in a region.  The Detroit and Lansing UCC could be be combined into a single region with a population equal to about 7 districts.  But this would reduce the total number of regions from 8 to 7, and any 8-region plan automatically defeats a 7-region plan.  The Lansing and Grand Rapids UCC could be combined into a single 2-district region.  But this will create a band across the state.  The area south of the band has a population equivalent to 2.4 districts, too large for two regions, but too small for 3 regions.

[Torie]

Somehow I knew that is what you would do.  For erosity, would not a map with juts containing now much area, but a lot of population, garner far less of a penalty, as compared with what makes for the minimum line length of more rural districts large in area, unless you somehow take a ratio of line length to population for subsets of each CD? Your method really emphasizes overall equality in population. That will tend to result I suspect in "uglier" maps. Anyway, it will be interesting to compare what your map looks like that gets the high score with your system vis  a vis Mike's, and get forumite reaction to it. Good luck!

Can you give me a hypothetical example of the bolded part?  I'm not sure what you are saying.

Think of a long thin tendril that is not very big, but contains a lot of people. Picture it being in Manhattan or something. The overall effect on the line length is trivial. The psephological impact might be large.

[Torie]

Below is Ohio. It has the requisite two macrochops, plus 3 microchops, one requisite I-chop between Summit and Cuyahoga Counties into the Cleveland UCC between OH-12 and OH-14, plus one microchop of a town, and a macrochop of Columbus (kind of unavoidable), but no hood chop within Columbus. The trickiest part was playing the anti-erosity game in Licking County. The map has 3 uncompetitive D districts (OH-09 barely at 5.6% Dem PVI), 2 competitive D districts, 2 even districts (both on the cusp of being competitive Dem, and both probably are now, particularly OH-01), 4 competitive Pub districts, and 5 uncompetitive Pub districts. None of the competitive CD's are really that competitive, except perhaps Pub OH-14). The split of Canton and Akron into two UCC's helped the Pubs push the Canton CD into the competitive Pub column.

As to the line between OH-11 and OH-08 on my map, this is one case where an extra I chop might be worth it, because it saves two highway cuts doing it that way, and thus two erosity points. I must say, I find Mike's system works extremely well, and I congratulate him. I still favor all of my "friendly" amendments, as to which I am making absolutely no headway with him, but that is OK. This little show alas is unlikely to hit Broadway in any event. Pity that.

[jimrtex]

To be connected, counties must be contiguous.   In general there must be a direct, non-circuitous way to travel between the counties, particularly considering the distribution of the population.  There is no requirement that the route be entirely in the two counties, but if the route goes through other counties it should not be through population concentrations, or drawn in a way to evade the population concentrations.

Can this be defined in a way that a person sitting at a computer with a program such as MapQuest could determine whether such a connection exists? As I read this it has a substantial subjective component, and two groups working on the connectivity map could reasonably come up with two different plans.

The organizers would define the connectivity map.  Presumably if they provided an app, this could be a displayable layer.  Any scoring would verify connectivity.

The Census Bureau has a county contiguity file for the United States, which can be trimmed to an individual state (eg the census file includes the contiguity between Monroe, MI and Lucas, OH). 

From census files the land boundary (direct) distance and areas can be obtained.  The substantiality of each border can be calculated.  I have used the border distance divided by the square root of the area of the smaller county.  We can imagine that the counties are wood blocks that have been glued together.  If there is longer surface the bond will be tighter.  Shorter, and we might be able to break them apart.  The size of block is an indication of the leverage that may be applied.

Where we can twist the blocks apart, we might use pegs or reinforcing rods.  This is the equivalent to roads connecting the counties.  Some of the reinforcing rods might be outside the boundary of the junction, but they can be seen as reinforcing the connectivity, particularly if they are not through the populated areas.

I used the primary/secondary road shapefile from the census bureau, as well as the urban areas shapefile.

If the organizer were a public commission, they could prepare a preliminary definition of connectivity, which would be reviewed by the government of each county.

[jimrtex]

Somehow I knew that is what you would do.  For erosity, would not a map with juts containing now much area, but a lot of population, garner far less of a penalty, as compared with what makes for the minimum line length of more rural districts large in area, unless you somehow take a ratio of line length to population for subsets of each CD? Your method really emphasizes overall equality in population. That will tend to result I suspect in "uglier" maps. Anyway, it will be interesting to compare what your map looks like that gets the high score with your system vis  a vis Mike's, and get forumite reaction to it. Good luck!

Can you give me a hypothetical example of the bolded part?  I'm not sure what you are saying.

Think of a long thin tendril that is not very big, but contains a lot of people. Picture it being in Manhattan or something. The overall effect on the line length is trivial. The psephological impact might be large.

Definition of districts within multi-region CDs would be at a second phase.

In New York the initial phase would define 6 regions, a 19-district region for the NY UCC, and 2-district regions for Buffalo, Rochester, and Albany-Schenectady, and 2 single-district regions.

[muon2]

Here's a test case to try to understand the role (or not) of microchops and their potential interaction with single and multi-county UCCs.

MI muon2 2015A


There are no chops except in the big three counties and Detroit neighborhoods are whole. There is an extra chop of the Detroit UCC, instead of in Lansing like with Torie's plans. There is also an extra chop in Oakland to bring CD 14 over 50% BVAP, much like the IRL map. The study is in CD 7, which is slightly under the 0.5% threshold below quota, but within a microchop of the quota.

The neighboring CDs are above quota and could be used to bring CD 7 up. One could move two townships on the eastern edge of Kalamazoo (pop 3276), the southwestern township of Eaton (pop 3150), or Rockwood in Wayne (pop 3289) to make all the districts within deviation of quota.

Without the last shift identified above the CHOP score would be 7 for UCCs, 7 for counties, and 1 for Detroit. That's a low score of 15. It could go down to 14 if a 47% BVAP in Wayne would satisfy the VRA allowing an Oakland chop to be eliminated. For comparison trainB was a CHOP of 16.

But that doesn't include the fix to CD 7. If it is a pure non-scoring microchop, then the above paragraph applies. If it is full scoring chop then it matters which of the three UCC choices I use. In Wayne or Eaton it creates an additional UCC chop as well as a county chop, but in the single-county UCC Kalamazoo, there would be no UCC chop. That seems strange to me. If it gets a fractional score as suggested by Torie, that leaves the question of the UCC penalty up in the air.

Should the three choices outlined above score equally on CHOP or not? Should the fact that it's a microchop matter for either the UCC or the county chop? If it matters, should it only matter for one of the two possible scores?

Edit: It should say 8 UCC chops, not 7. I was focusing on the microchop impact, and forgot to count the whole county chop from CD 8 in the Detroit UCC.

[traininthedistance]

But that doesn't include the fix to CD 7. If it is a pure non-scoring microchop, then the above paragraph applies. If it is full scoring chop then it matters which of the three UCC choices I use. In Wayne or Eaton it creates an additional UCC chop as well as a county chop, but in the single-county UCC Kalamazoo, there would be no UCC chop. That seems strange to me. If it gets a fractional score as suggested by Torie, that leaves the question of the UCC penalty up in the air.

Hm.  You could probably guess that I'd advocate for microchops to score, and just score the same as any old chop, so that the above paragraph wouldn't apply.  There are a few possible fixes to what you find strange:

* perhaps microchops shouldn't incur the UCC penalty, unlike I-chops and macro chops (since I really haven't left any role for rewarding microchops in my thinking, this might be an opportunity to carve out a role for them after all)
* perhaps single-county UCCs should incur penalties for being chopped after all
* perhaps it's okay to live with that as an artifact of the scoring system

I"m honestly undecided as to which of the three is best.  Possibly need a day or two to mull it over- there's a part of me that wants to say Option 2 is the best, and single-county metros deserve some measure of protection as well, TBH.

...

I feel like this map is an even better test case, though, for that question I asked earlier regarding Pittsburgh and having multiple districts span the UCC boundary.  In Detroit, there are a full four districts which are partially within the UCC and without it.  That seems like... an abuse of the system to my eyes.  (As well as a traveling chop, which I guess is no big deal anymore, but I remember was verboten in really early attempts at these rules.)  Almost feel like it makes a case for maybe not having unlimited flexibility in that arena, and dinging maps that don't try to keep as many UCC districts as they can entirely within the UCC.

[traininthedistance]

Below is Ohio. It has the requisite two macrochops, plus 3 microchops, one requisite I-chop between Summit and Cuyahoga Counties into the Cleveland UCC between OH-12 and OH-14, plus one microchop of a town, and a macrochop of Columbus (kind of unavoidable), but no hood chop within Columbus. The trickiest part was playing the anti-erosity game in Licking County. The map has 3 uncompetitive D districts (OH-09 barely at 5.6% Dem PVI), 2 competitive D districts, 2 even districts (both on the cusp of being competitive Dem, and both probably are now, particularly OH-01), 4 competitive Pub districts, and 5 uncompetitive Pub districts. None of the competitive CD's are really that competitive, except perhaps Pub OH-14). The split of Canton and Akron into two UCC's helped the Pubs push the Canton CD into the competitive Pub column.

Below is a better Ohio. 













Plenty of chops are, well, chopped.  The Cincy-Dayton assemblage loses a county cut.  The Columbus area loses two county cuts.  The Cleveland UCC loses a county cut: it's not requisite to have more than 3 districts in there (you do need to send Akron-Portage somewhere, but that somewhere doesn't need to be in Cuyahoga). 

As is to be expected, the only municipality chopped is Columbus, which is indeed unavoidable.  But none of the weird fragmentary townships in Franklin/Hamilton get separated, nor do the apparent Columbus subunits.

Oh, and hey, the inequality is lower too.  Haven't counted erosity (would help if the Torie map zoomed in on the metros) but with all the saved cuts in places like Licking and such this map has a great chance of even winning that derby.

...

Kinda want to end this post with one of those mic drop GIFs the kids these days seem to love.  Boom.

[muon2]

I feel like this map is an even better test case, though, for that question I asked earlier regarding Pittsburgh and having multiple districts span the UCC boundary.  In Detroit, there are a full four districts which are partially within the UCC and without it.  That seems like... an abuse of the system to my eyes.  (As well as a traveling chop, which I guess is no big deal anymore, but I remember was verboten in really early attempts at these rules.)  Almost feel like it makes a case for maybe not having unlimited flexibility in that arena, and dinging maps that don't try to keep as many UCC districts as they can entirely within the UCC.

I think this map shows how the UCC penalty works. In trainB there are 5 Detroit UCC chops due to the 6 CDs covering it. There are also 5 county chops in the Detroit UCC (2 Wayne, 2 Oakland, 1 Macomb). There are also 4 county chops outside the Detroit UCC.

In muon2A above I eliminated all the outstate county chops and moved the remaining necessary chops to the Detroit UCC to get a total of 7 (3 Wayne, 3 Oakland, 1 Macomb). Even though this is 2 lower than the total in trainB, the UCC penalty is 2 higher since 8 CDs cover the Detroit UCC. In addition those extra chops into Wayne and Oakland greatly increase the erosity, so by virtue of the UCC penalty the trainB map would prevail.

[Torie]

The fan out of UCC CD's the way Train did of the Columbus UCC per Mike's rules, is indeed an abuse of the system it seems to me. It defeats the whole purpose of UCC's in my view. That purpose was to limit the fan out of the UCC population. Yes, it may be severing all of Licking is a good idea, but not at the no penalty  movement of the UCC based CD's fanning outside the UCC to where they need not go, with the ensuing maxi chop of Franklin causing the CD's to suck up Pickaway and Madison Counties. Indeed, it looks like a Dem gerrymander to me. I guess the "fix" for UCC's which require a chop in, is to assess just how large the chop in is over the minimum, and to assess an additional penalty point for each additional macrochop size increment. For UCC's which require a chop out, the baseline figure would be the minimum size of the chop out. I guess we are really talking about the same thing. In looking at the Columbus UCC as requiring a chop in, it's the additional population in Licking involved in the whole county severance. If looking at it as a chop out, it's the population of Pickaway plus Madison. We just think of it as chops in for UCC's with a population just under a an even number of CD's (1.51 to 1.99), and a chop out where just over such whole number (2.01 to 2.49).  

Train has a chop into the UCC of Columbus that involves an additional population of 99,463 people over my map by virtue of his total severance of Licking (represented by the population of Madison plus Pickaway, less the population of my microchop of Madison), so that would be an additional two chop penalty points over my map. Balance that against the one chop penalty point I get for chopping Licking (well actually not, since Train gets a penalty point for the whole county severance anyway), plus the additional erosity highway cut within Licking that my map entails over his (it was hard work there to avoid two highways being severed). Sure, Train's map works for a Democratic favorable plan here, but in some states, the same device could be used to erase a Democratic inner city district, where there needs to be a macrochop into the UCC. Train also has a much bigger chop into the Dayton UCC than the minimum. My chops into both UCC's were the minimum in population, plus the population involved with respect to one microchop into Madison County.

Another issue is should it be allowed without penalty, absent VRA concerns, to get close to bisecting big cities, rather than minimize the size of the chops of subunits as well, again using the one point per macrochop increment penalty (so, for subunits, a quarter point for a microchop, a half point for an I chop, and one point per macrochop increment penalty, to be consistent with my scheme)? Train's map basically gets close to evenly bisecting Columbus, along with slicing up the black population in the wash (albeit legally here). I don't think that is acceptable without penalty myself; it should be penalized. It seems to me that subunits should be treated the same as counties for this purpose.

Which gets back to Jimtex's double chop of the Lansing UCC, where the amount of the total chop in was about the same as my larger one chop in, but his score crashed. There, it really should not, given that the same population was involved. But in Train's map, involving much larger population sized UCC related chops than mine, where one bisects the big population county (and city), and causes a huge fan out, there is a problem. Often the VRA will prohibit it, but that is not in play in Columbus, so one can just do a huge chops of the UCC and City itself with impunity. I think my proposed fix appropriately "saves" Jimtex's map, while penalizing Train's map.  

Speaking of the VRA, in Train's map the BVAP percentage of the Cleveland centered CD crashes (down to 30.5%). If a 46% BVAP CD as I drew it (lots of socially liberal whites - e.g., Parma is not in the CD, but Shaker Heights is), constitutes a CD that is deemed able to elect a congressperson of the minority population's choice, then Train's map is illegal. A lot will ride on that lawsuit, because the blacks will be very unhappy with his map.

As to the CD-07 issue in Mike's MI map, I see no reason to treat single county UCC's differently from any other county.  Any macrochop, I chop or microchop of a county  scores an additional penalty, 1 point per macrochop increment (2 points for the first incremental macrochop), 1 point for an I chop, and 0.5 points for a microchop, respectively. So Mike can pick any county he wants for his microchop, and it generates a half point penalty. So his map gets a chop score (assuming he does not reach for a 50% BVAP CD), of 15.5, Train's gets 16, and my map gets 17 (I don't remember now if Train's and my scores counted the Detroit hood chop, which has now been reduced to a microchop in my map, which should get a quarter point penalty), and that sounds about right, because my map I suspect has the lowest erosity score, by a fair margin, while Mike's perhaps has the highest (that would be interesting to check).

[traininthedistance]

The fan out of UCC CD's the way Train did of the Columbus UCC per Mike's rules, is indeed an abuse of the system it seems to me. It defeats the whole purpose of UCC's in my view. That purpose was to limit the fan out of the UCC population. Yes, it may be severing all of Licking is a good idea, but not at the no penalty  movement of the UCC based CD's fanning outside the UCC to where they need not go, with the ensuing maxi chop of Franklin causing the CD's to suck up Pickaway and Madison Counties. Indeed, it looks like a Dem gerrymander to me. I guess the "fix" for UCC's which require a chop in, is to assess just how large the chop in is over the minimum, and to assess an additional penalty point for each additional macrochop size increment. For UCC's which require a chop out, the baseline figure would be the minimum size of the chop out. I guess we are really talking about the same thing. In looking at the Columbus UCC as requiring a chop in, it's the additional population in Licking involved in the whole county severance. If looking at it as a chop out, it's the population of Pickaway plus Madison. We just think of it as chops in for UCC's with a population just under a an even number of CD's (1.51 to 1.99), and a chop out where just over such whole number (2.01 to 2.49).  

You do realize that Fairfield is part of the Columbus UCC, not just Licking?  And it's not like your map perfectly conserves all-UCC districts; the chop of 15 into Huron sees to that.  

Train has a chop into the UCC of Columbus that involves an additional population of 99,463 people over my map by virtue of his total severance of Licking (represented by the population of Madison plus Pickaway, less the population of my microchop of Madison), so that would be an additional two chop penalty points over my map. Balance that against the one chop penalty point I get for chopping Licking (well actually not, since Train gets a penalty point for the whole county severance anyway), plus the additional erosity highway cut within Licking that my map entails over his (it was hard work there to avoid two highways being severed).

Okay, now you're just making up numbers.  Two chop penalty points only works if your county cut of Licking somehow magically doesn't count, to which I say nice try.  By this scoring system there would be no incentive to keep counties whole within a UCC.

Sure, Train's map works for a Democratic favorable plan here, but in some states, the same device could be used to erase a Democratic inner city district, where there needs to be a macrochop into the UCC. Train also has a much bigger chop into the Dayton UCC than the minimum. My chops into both UCC's were the minimum in population, plus the population involved with respect to one microchop into Madison County.

I'd like to see the SKEWs calculated here: pretty sure mine is lower than yours, so best to not whine about "gerrymanders", just sayin'.

You know... thing is I actually could agree to having a penalty for not maximizing all-UCC districts, in which case yes my Dayton and Columbus would get dinged.  I kind of suspect that is an area where fractional points would be appropriate; they were in fact split as such for the goal of eliminating county cuts, and I still think that's a good goal, but maybe it shouldn't be entirely scot-free.  

Of course, if this penalty gets put back in we'll all have to redraw our Grand Rapids areas.

Which gets back to Jimtex's double chop of the Lansing UCC, where the amount of the total chop in was about the same as my larger one chop in, but his score crashed. There, it really should not, given that the same population was involved, but in Train's map, involving a much larger population than mine, where one bisects the big population county, and causes a huge fan out, there is a problem. Often the VRA will prohibit it, but that is not in play in Columbus, so one can just do a huge chop of the City itself with impunity. I think my proposed fix appropriately "saves" Jimtex's map, while tanking Train's map.  

"Appropriate" my ear.  

Speaking of the VRA, in Train's map the BVAP percentage of the Cleveland centered CD crashes (down to 30.5%). If a 46% BVAP CD as I drew it (lots of socially liberal whites - e.g., Parma is not in the CD, but Shaker Heights is), constitutes a CD that is deemed able to elect a congressperson of the minority population's choice, then Train's map is illegal. A lot will ride on that lawsuit, because the blacks will be very unhappy with his map.

I was operating under the assumption that you can't draw a VRA district without Akron anyway, so that problem is moot.  I mean, you could goose the numbers on mine as well at the expense of considerable ugliness and propensity to use the VRA as a Republican gerrymander, for sure.

But the Cuyahoga lines could, if necessary, be shifted without changing anything else.

As to the CD-07 issue in Mike's MI map, I see no reason to treat single county UCC's differently from any other county (other than perhaps the population shift issue discussed with Train's Ohio map). Any macrochop, I chop or microchop of a county  scores an additional penalty, 2 points, 1 point, and 0.5 points respectively. So Mike can pick any county he wants for his microchop, and it generates a half point penalty. So his map gets a chop score (assuming he does not reach for a 50% BVAP CD), of 15.5, Train's gets 16, and my map gets 17 (I don't remember now if Train's and my scores counted the Detroit hood chop, which has now been reduced to a microchop in my map, which should get a quarter point penalty), and that sounds about right, because my map I suspect has the lowest erosity score, by a fair margin, while Mike's perhaps has the highest (that would be interesting to check).

Well, I treat all chops as 1 point, as is good and proper.  Keep in mind that I have not signed on to your sliding scale chop regime, and am unlikely to.  I'm willing to treat them differently for erosity purposes (so that all else being equal small chops can be preferred as a tiebreaker on that measure), but at the end of the day a chop is a chop is a chop far as I'm concerned.  (My first map had a Detroit hood chop, but I fixed that so it no longer exists.)  And, pretty sure if we're going to penalize maps for not maximizing the number of districts entirely within the UCC, muon's latest Michigan would get hit more than that?

...

I'll probably be AFK all day, but should be back for more soon.

[Torie]

1. Huron isn't part of a UCC. If it were, my map should be penalized.

2. I am aware that removing Fairfield is a chop. Both of our maps do that. It is part of a minimum chop size. I was focusing on where the scoring of our respective maps should differ.

3. Yes, my chop of Licking counts as a chop. Your whole county severance of Licking counts as a chop. I take your point however. I should get an extra chop point over yours, and the only significance of whole county chops should be their population counts as part of the size of the chop. We both get macrochop increments points for the size of our respective chops, with you having more increments than mine for an extra two point penalty, but I get an I chop penalty on top of that (which is why a county with one macrochop gets two points, one for the I chop, and 1 for the macrochop as it were). Plus I have an additional highway cut. So in that sense, at least before we get to the issue of your hideous near equa-bisecting of Columbus (), our maps here are basically tied.  If you had not done your Columbus thing, I agree that our maps in this area should be deemed about even. Good point by you indeed, Train.

4. Glad we agree on the UCC fanout issue, which is what I am really focusing on, along with the size of chops within subunits, and yes, that does mean revised MI maps. When I drew mine initially, I though Barry and that other county (Ionia?) were in the GR UCC, and Ottawa was not. And then it turned out there was no problem with the size of the macrochop in Mike's scheme, so the slicing off Ottawa was a freebie under Mike's rules (other than counting towards the one macrochop penalty point, but if MI-02 macrochops into Kent anyway in addition to sucking up Ottawa, then yes, a total freebie). It should not be. You take the population of the smaller of the two pieces of the GR UCC, and divide by the macrochop increment, to calculate the number of penalty points, in addition to the I chop of Kent. Presumably the population of Ottawa plus the portion of MI-02 in Kent, is the smaller of the two pieces in population. The penalty points that could be avoided would involve the population in MI-03 that should be in Ottawa and Kent, but is not, because it heads off west instead.

5. Your skew might well be "better" than mine indeed. But we don't "gerrymander" to get there. It factors in later after the scoring is done to break ties. If we did, the Pubs could demand a hideous gerrymander of Massachusetts.

6. The VRA test is about minority's electing candidates of their choice. The 50% figure is just a safe harbor. If a lower figure is deemed to do the trick, that is possible to effect within the subject community of interest, the VRA is still in play. Granted the law might not be totally clear on that. I am not sure there has been a case where it is possible to draw a district close to 50%, but not quite, but the lower figure is enough for the minority to elect the candidate of their choice, but the CD is not drawn, and thus the minority is not able to elect a candidate of their choice. In all events, as I said, what you did would be highly unpopular.

7. I know we disagree about the sliding scale, and we will just have to agree to disagree. I think beyond the number of chops, the size of chops is of the very essence of what makes good maps. You seem to agree when the concept involves multi county UCC's. I think the concept should be applied everywhere, with the impact of multi county UCC's being simply  to sum the population of all of the chops involving the UCC, for purposes of calculating the number of penalty points to be assessed. KISS, the concept Mike likes to invoke, except when he doesn't want to.

8. Mike's map would be a chop point disaster under my system. Given that MI-05 (assuming that is the smallest population within the Detroit UCC of any of the CD's) should not be in the UCC at all, you would add the population within the Detroit UCC that is in MI-05, or to calculate it more easily here, since it is offset by a whole county Livingston chop into the Detroit UCC that is totally needless, take the 180,967 population of Livingston County, and divide that by the macrochop size of 35,299, which equals 5.126 machochop increments, or 5 penalty points. If his map is high scoring, it makes the whole concept of UCC's, and trying to avoid large numbers of people being involved in chops in general, be it UCC's or counties, or subunits, but a chimera. We might as well pack up our bags and go home.

[jimrtex]

The submitted map can be represented as a graph, with the vertices representing the regions, and the links representing the boundary between the regions.   Since we will making our population shifts/chops along these boundaries, we can eliminate any links where there are not connected counties.  There were none in this example, but in Michigan they might occur if four regions met at the junction of four counties.  In that case, the diagonally opposite regions would not be linked.

[traininthedistance]

1. Huron isn't part of a UCC. If it were, my map should be penalized.

2. I am aware that removing Fairfield is a chop. Both of our maps do that. It is part of a minimum chop size. I was focusing on where the scoring of our respective maps should differ.

3. Yes, my chop of Licking counts as a chop. Your whole county severance of Licking counts as a chop. I take your point however. I should get an extra chop point over yours, and the only significance of whole county chops should be their population counts as part of the size of the chop. Good point by you indeed, Train.

4. Glad we agree on the UCC fanout issue, which is what I am really focusing on, along with the size of chops within subunits, and yes, that does mean revised MI maps. When I drew mine initially, I though Barry and that other county were in the GR UCC, and Ottawa was not. And then it turned out there was no problem with the size of the macrochop, so slicing off Ottawa was a freebie under Mike's rules. It should not be.

5. Your skew might well be "better" than mine indeed. But we don't "gerrymander" to get there. It factors in later after the scoring is done to break ties. If we did, the Pubs could demand a hideous gerrymander of Massachusetts.

6. The VRA test is about minority's electing candidates of their choice. The 50% figure is just a safe harbor. If a lower figure is deemed to do the trick, that is possible to effect within the subject community of interest, the VRA is still in play. Granted the law might not be totally clear on that. I am not sure there has been a case where it is possible to draw a district close to 50%, but not quite, but the lower figure is enough for the minority to elect the candidate of their choice, but the CD is not drawn, and thus the minority is not able to elect a candidate of their choice. In all events, as I said, what you did would be highly unpopular.

7. I know we disagree about the sliding scale, and we will just have to agree to disagree. I think beyond the number of chops, the size of chops is of the very essence of what makes good maps. You seem to agree when the concept involves multi county UCC's. I think the concept should be applied everywhere, with the impact of multi county UCC's being simply  to sum the population of  all of the chops involving the UCC, for purposes of calculating the number of penalty points to be assessed. KISS, the concept Mike likes to invoke, except when he doesn't want to.

8. Mike's map would be a chop point disaster under my system. Given that MI-05 (assuming that is the smallest population within the Detroit UCC of any of the CD's) should not be in the UCC at all, you would add the population within the Detroit UCC that is in MI-05, or to calculate it more easily here, since it is offset by a whole county Livingston chop into the Detroit UCC that is totally needless, the population of Livingston County, that has a population of 180,967, which divided by the macrochop size of 35,299, equals 5.126 machochop increments, or 5 penalty points. If his map is high scoring, it makes the whole concept of UCC's, and trying to avoid large numbers of people being involved in chops in general, be it UCC's or counties, or subunits, but a chimera. We might as well pack up our bags and go home.

Yeah... I think we're actually closer to "on the same page" than I thought we were earlier.

As it so happens I just noticed a couple rogue precincts screwing up District 6, so my map will need some re-drawing anyway.  Will take into account the UCC fans preemptively this time.  I expect that Columbus will be de-fanned, but the savings in county cuts for Dayton might mean that I'd live with the hit there.  I kinda feel, just gut-wise, that having two districts span the UCC boundary (so long as the minimum # of districts are within the UCC) doesn't bother me too much (hence my suggestion of possibly fractional chop penalties), but it's when you add in a third district that it feels like a Problem.  My Columbus is indeed problematic by that definition, so back to the drawing board for it.

I also might live with the hit in Grand Rapids, or not.  Definitely living with the hit in Pittsburgh, I think.

Some guidance on what exactly "safe harbor" for BVAP in Cuyahoga is would be nice.  It indeed looks like 46% BVAP is the best you can get, obviously at the expense of considerable erosity for both of us.  Obviously if the VRA is in play at all 30 percent is not going to fly, but I wonder if something cleaner in the low 40s or so would work.

[Torie]

There is no bright line test under the VRA for this issue. It is fact specific. But where it is possible to draw a pretty compact CD (the erosity involves the CD's around the Cleveland CD due to all the other rules in play, not the CD itself) with a higher BVAP, and involving no chops in particular, but instead draw one with a lower one, I suspect the courts will look at it with a jaundiced eye, unless SCOTUS deems it open season on minorities no matter what if there is not a 50% BVAP CD to be had in the hood. Given that your map would be politically dead in the water anyway, I would suggest you just assume that you need to keep the BVAP very near 46% (say within 1% anyway).

Just assume that your goal is to move OH-14 into the equal category politically rather than the competitive R category (eroding off 1.3% in Pub PVI), and see if you can do that with say the BVAP being at least 45.5% - 45% being the absolute minimum, but try for 45.5% if you can (mine is 46.6%, and that is just about the max absent generating a host of chops, which might get it up to about 47%).

FWIW, below is about the minimum chop size of Columbus, effected by me, with some minor modifications per my previous map, without the zoom erosity score, however calculated, going wild. You might compare your chop size to this chop size of 173,294, more or less, for comparison purposes. You, in your map have about twice that, plus or minus, for about 5 more penalty points if my system were adopted, plus or minus one point. To get both Columbus based CD's down to about the same PVI ("competitive" Dem), or reasonably close to it, it would be about 3 penalty points more per my system, if skillfully done, without being beat up by more erosity points, however scored per the zoom regime, and assuming that Licking is totally chopped off. Addendum: actually, without more erosity points, you can put Arlington and that other burb into OH-15, and get the chop size down to about 125,000 or so (adding some precincts of Columbus way off to the east that I forgot to count that are in OH-15. So 3 penalty points is about the minimum.

\\

[muon2]

The IL Dems successfully defended state rep districts with 46% BVAP in court, and that was with more compact 50% BVAP districts available. In Cook the data supported a finding that polarized voting was not prevalent to the extent that the black minority would be unable to elect a candidate of choice. It helped that major black groups like the Urban League were supporting the Dems position.

In the OH competition, a threshold of 48% BVAP was used for CDs based on consultation with black community groups. They recognized that a 50% BVAP CD would need to reach into Akron, where as 48% could be put together in Cuyahoga. The Dem map that was filed in response to the Pub plan was between 48% and 50%.

However, a Pub-gerrymandered map that went under 50% BVAP would almost certainly be subject to attack by Dem-leaning minority groups. That is why Pubs stick to the 50% threshold.

[muon2]

Hm.  You could probably guess that I'd advocate for microchops to score, and just score the same as any old chop, so that the above paragraph wouldn't apply.  There are a few possible fixes to what you find strange:

* perhaps microchops shouldn't incur the UCC penalty, unlike I-chops and macro chops (since I really haven't left any role for rewarding microchops in my thinking, this might be an opportunity to carve out a role for them after all)
* perhaps single-county UCCs should incur penalties for being chopped after all
* perhaps it's okay to live with that as an artifact of the scoring system

I"m honestly undecided as to which of the three is best.  Possibly need a day or two to mull it over- there's a part of me that wants to say Option 2 is the best, and single-county metros deserve some measure of protection as well, TBH.

These are some interesting ideas, here's my take.

Exempting microchops from the UCC penalty, but otherwise counting as a chop would cause all three of my possible placements to be equal in terms of CHOP. That would push the choice to which ever improves EROSITY or INEQUALITY, which seems like the right reason to choose between the three options for placing the microchop.

Causing single-county UCCs to have a penalty for the UCC as well as the county double the points there. The use of the chop in Jackson by Torie and you would garner an extra point, and that seems severe to me. I fear this would cause plans to preferentially place all chops in small counties.

There's nothing inherently wrong with treating it as an artifact. Part of why I brought up the plan was to show a discrepancy and see if it was worth fixing, or would a fix be more complicate than the problem.

[muon2]

Here's my plan to reduce chops in MI without relying on microchops. I used a UCC chop of whole county Livingston and a threshold of 47% BVAP for the Detroit CDs. This allowed the removal of one chop in Oakland and a chop outside of the Detroit UCC.

The Muskegon chop is a macrochop and the townships are used to determine cut links there. The other two outstate chops are small. The chop in Ionia isn't a microchop, but it could be if it were moved to the SW corner of Eaton. However if microchops get no advantage as county or UCC chops then to place it there would be counterproductive, despite a better shape.

The Detroit CDs are 48.3% and 47.5% BVAP for CDs 13 and 14 respectively. It's quite possible that the BCVAP in CD 13 is over 50% since there is a 7.5% HVAP population and a large Arab population which would have high non-citizen rates.

The score for this plan muon2 B is
SKEW 1 (R)
POLARIZATION 18
INEQUALITY 10
CHOP 15
EROSITY 106

Compared to train B (I:10, C:16, E:117) this matches INEQUALITY and reduces both CHOP and EROSITY. It does not get erosity as low as Torie B or C (I:11, C:18, E:95) so it remains Pareto equivalent.

MI muon2 2015B

[traininthedistance]

Man, the more of these maps I'm seeing, the more I'm convinced that:

A) We should have some penalty for not keeping as many large-UCC districts entirely within the UCC as possible.  Torie and I seem to be on the same page, here, even if we haven't figured out the mechanism of the penalty seems like we both believe some penalty is warranted.
B) This is perhaps a more lonely crusade, but I increasingly feel there ought to be some recognition for Combined Statistical Areas, where the Census delimits separate metros but the facts on the ground veer towards a common regional identity.  If we're getting rewarded for splitting Saginaw/Bay City/Midland (or Cleveland/Akron/Canton, or Dayton/Springfield, or any similar assemblage of nearby mid-sized cities that are functionally the same region, and nigh-universally felt as such), then IMO something's gone wrong.

[muon2]

Man, the more of these maps I'm seeing, the more I'm convinced that:

A) We should have some penalty for not keeping as many large-UCC districts entirely within the UCC as possible.  Torie and I seem to be on the same page, here, even if we haven't figured out the mechanism of the penalty seems like we both believe some penalty is warranted.
B) This is perhaps a more lonely crusade, but I increasingly feel there ought to be some recognition for Combined Statistical Areas, where the Census delimits separate metros but the facts on the ground veer towards a common regional identity.  If we're getting rewarded for splitting Saginaw/Bay City/Midland (or Cleveland/Akron/Canton, or Dayton/Springfield, or any similar assemblage of nearby mid-sized cities that are functionally the same region, and nigh-universally felt as such), then IMO something's gone wrong.

Trying to score by eye is tough. My latest map has as many CDs entirely in the Detroit UCC as any of the other scored offerings. I made a conscious choice to add a chop in the Detroit area to rid the plan of two others. It's similar to Torie placing a chop in the Lansing UCC to reduce erosity.

The UCC factor was hard to work out when we started in 2013. Not all CSAs work as well as others, and that leads to subjective choices. In some states the MSAs spread into thinly populated areas, so we had to construct an objective measure as what counties were really the built up area. The goal is to recognize an objective community of interest.

I've tried to design scoring so that tradeoffs are conscious and not incremental. Some systems become exercises in shifting single census blocks around to get fractionally better scores without demonstrably changing the plan, and I want to avoid that. At the same time I don't want the only permissible shifts to be so large that one cannot break a UCC. To me that should be avoided as much as a requirement that no county can be split regardless of the shape that might result.

[jimrtex]

B) This is perhaps a more lonely crusade, but I increasingly feel there ought to be some recognition for Combined Statistical Areas, where the Census delimits separate metros but the facts on the ground veer towards a common regional identity.  If we're getting rewarded for splitting Saginaw/Bay City/Midland (or Cleveland/Akron/Canton, or Dayton/Springfield, or any similar assemblage of nearby mid-sized cities that are functionally the same region, and nigh-universally felt as such), then IMO something's gone wrong.

The risk with using CSA is either overconstraining or underconstraining.

Is it desirable to have a district starting in Lenawee coming in to Wayne County if it can avoid a crossing of the Wayne-Macomb border (underconstraint).

Not only do we have Saginaw/Bay City/Midland, there is Kalamazoo-Battle Creek which is 4 counties.  Lansing drags in Shiawassee.   Mount Pleasant-Alma forces Gratiot and Isabella to stick together.  Muskegon gets added to Grand Rapids.   Genesee  and Washtenaw get added to Detroit.

We haven't said that there can't be some subjective judgment that would keep Saginaw, Bay City, and Midland together.  But it must be something that works quantitatively as well.

[Torie]

The IL Dems successfully defended state rep districts with 46% BVAP in court, and that was with more compact 50% BVAP districts available. In Cook the data supported a finding that polarized voting was not prevalent to the extent that the black minority would be unable to elect a candidate of choice. It helped that major black groups like the Urban League were supporting the Dems position.

In the OH competition, a threshold of 48% BVAP was used for CDs based on consultation with black community groups. They recognized that a 50% BVAP CD would need to reach into Akron, where as 48% could be put together in Cuyahoga. The Dem map that was filed in response to the Pub plan was between 48% and 50%.

However, a Pub-gerrymandered map that went under 50% BVAP would almost certainly be subject to attack by Dem-leaning minority groups. That is why Pubs stick to the 50% threshold.

Can you get to 48% BVAP without chops of subunits? Can you get there without such a map causing the map score to tank whether using your system, or your system as modified by me?  If Ohio enacted into law "our" system, I suspect that would tend to defang any such lawsuit, because there would be objective reasons per previously enacted law to cut down the BVAP a tad, tied to good map making. That is a different context, from a map that chops here, there and everywhere, but then suddenly does not when it comes to the Cleveland district.

I am falling in love with my system.   I find it simple and intuitive, focusing on chop size, along with the number of chops, universally applied with just the UCC aggregation overlay.