Local vs regional road connections

[jimrtex]

The population increase in Madison is almost entirely in Winterset is my impression. Next to no housing tracts have been built in the NE corner of Madison yet. But Winterset has some new subdivisions. Not to the south however, because that is where the Torie farm is, and Torie isn't selling yet.

Between 2000 and 2010, the 7 townships on the north and east county lines (near I-80 and I-35) increased by 893. Winterset and the 4 surrounding townships 727, and the remaining 5 townships on the south and west sides lost 70.

If you want to live in the country, you can have a job in Des Moines and commute to a small tract of land that would be too small to support full time farming.

That's interesting. I wonder if it was more on the north, or on the east. Guthrie is like Polk, but a point connection, so you know the answer.

Actually it was a trick question.  Guthrie and Madison are adjacent, Dallas and Adair are not.

The Dallas-Polk-Warren-Madison is a true 4 corners.

The fastest growing township on a percentage basis is Lee in the extreme northeast, 60% between 2000 and 2010. West Des Moines extends south of the Polk County line, and Cummings is south of that and reaches the Madison line.  The numeric increase is small, from 468 to 747.  Along the section line west from the first I-35 interchange in Warren County there are quite a few single houses.  And further south there are some acreage developments (5 or 10 acre lots, around some ponds).

The largest townships outside of Winterset are Madison near I-80 and South near I-35.  They include Earsham and St. Charles, and increased from 1238 to 1411, and 1279 to 1457.

[jimrtex]

To clarify I had lengthy conversations during the 2011 remap with experts hired in the past by the controlling party. One repeated comment they made was that contiguity without connection (rivers, railroads, etc) allowed them to design some of their best gerrymanders. So, they suggested that one of the best rules one could enact to curb the power of gerrymanders was to deny them that ability.

Were they using building blocks such as counties at large scale, with townships if necessary to split counties?

My connection between Cleveland and Akron is comprised of whole census blocks and contains not mere paved streets, but interstate highways.  I even took care to include the parts of a cloverleaf so you wouldn't have to leave the district driving in either direction.

[jimrtex]

I'm looking at the local connections on my NC map. I'll start with the western end. If there is a modification to the connection definition, we should see how it plays in the mountains.

Cherokee (Murphy) to Macon (Franklin)
The direct road is US 64 which is 49 mi and spends 27 mi in Clay. There are no urban areas in Clay and US 64 has a bypass around the Clay seat (Hayesville). Cherokee and Macon are contiguous and US 19/US 74 crosses the border, but only travels along the edge of Macon on its way north. To get to Franklin requires considerable travel on a winding local road (Wayah Rd or Junaluska then Wayah), so it's locally connected. This failed both the jimrtex and muon2 criteria.

The US 74 route is considerably longer (88 minutes vs 58 minutes).

The adjacency index is 0.309, and there is enough population in the Andrews area (about 25% of the population is in Valleytown township) to qualify the counties as connected.  But it as fast to backtrack to US 64 as to go US 74, or use the direct county roads.  The direct county road is slow (average speed 31 mph), which is less than 30 mph on a straight line.

Functionally, if you go northeast on US 74, you are getting on the north side of the ridge from Macon County.  Murphy is off the southwest end of the ridge, and US 64 keeps you south.  But that puts you through Clay County.

Cherokee (Murphy) to Graham (Robbinsville)
The direct road is US 129. Some renderings of US 129 have it clip the corner of Macon (Bing) while others show is straddling the county line (Mapquest). The satellite view shows it on the county line. I allow roads on the line to count in either county. This passes both the jimrtex and muon2 criteria.

Census maps have US 129 coincident with the Cherokee border with both Macon and Graham counties.  The direct route to Murphy and Andrews includes US 74.  Functionally, the border between Macon and Graham is an east-west ridge, that you are able to get around on the eastern end.

Graham (Robbinsville) to Macon (Franklin)
The direct road is NC 143 and NC 128 which is 45 mi and spends 14 mi in Swain. The route does not pass through any urban areas and doesn't approach the Swain county seat (Bryson City), though it does follow part of the preferred route one would take to get there from Graham. Graham and Macon are contiguous and a US highway crosses the border. One can use the the aforementioned local Wayah Rd (it's one of the NC secondary roads), so it's locally connected. This failed both the jimrtex and muon2 criteria.

You are most of the way from Robbinsville to Bryson City before you turn and go south. This is the route to Swain County, even NC 128 continues south.

[jimrtex]

I'm looking at the local connections on my NC map. I'll start with the western end. If there is a modification to the connection definition, we should see how it plays in the mountains.

These are the county pairs that I either made a note on or at least one of us classified as 'unconnected'. The other pairs can be considered to be trivially obvious that they are 'connected'. My believe is that 'contiguous' should imply 'connected', unless there is strong evidence to the contrary. That is why I am willing to let county officials override a classification of 'not connected', but that they may not override a classification of 'connected'.

Cherokee   Graham
Cherokee   Macon
Graham   Macon
Swain   Haywood
Haywood   Henderson
Haywood   Madison
Buncombe   Rutherford
Henderson   Rutherford
Yancey   McDowell
McDowell   Burke
Avery   Caldwell
Rutherford   Burke
Burke   Cleveland
Burke   Lincoln
Cleveland   Lincoln
Caldwell   Catawba
Lincoln   Iredell
Lincoln   Mecklenburg
Wilkes   Alleghany
Wilkes   Surry
Iredell   Cabarrus
Surry   Forsyth
Cabarrus   Union
Rowan   Stanly
Davidson   Guilford
Davidson   Montgomery
Randolph   Alamance
Rockingham   Alamance
Moore   Chatham
Moore   Cumberland
Chatham   Durham
Chatham   Harnett
Orange   Person
Columbus   Pender
Sampson   Pender
Sampson   Wayne
Johnston   Nash
Brunswick   Pender
Warren   Northampton
Duplin   Jones
Wilson   Pitt
Greene   Pitt
Halifax   Bertie
Lenoir   Craven
Pitt   Martin
Jones   Carteret
Hertford   Chowan
Gates   Camden
Gates   Perquimans
Pamlico   Carteret
Pamlico   Hyde
Chowan   Washington
Washington   Hyde
Washington   Perquimans
Carteret   Hyde
Perquimans   Tyrrell
Pasquotank   Tyrrell
Tyrrell   Camden
Tyrrell   Currituck

[jimrtex]

Graham (Robbinsville) to Macon (Franklin)
The direct road is NC 143 and NC 128 which is 45 mi and spends 14 mi in Swain. The route does not pass through any urban areas and doesn't approach the Swain county seat (Bryson City), though it does follow part of the preferred route one would take to get there from Graham. Graham and Macon are contiguous and a US highway crosses the border. One can use the the aforementioned local Wayah Rd (it's one of the NC secondary roads), so it's locally connected. This failed both the jimrtex and muon2 criteria.

Why does the above fail the Jimtex test? On mine, it is right on the cusp as to whether 14 miles is more than a third of the maximum length of the impinged county. If it does not exceed that, it still fails because the nik is not "direct" enough. The road is designed to go to Bryson City, not Franklin, and one needs to make a left turn off it to take the road to Franklin. The only thing going for it, is that it is the best way to get from Swain to Franklin, because the counties are so cut off from one another, that this circuitous route is the only way to do it. Which sort of emphasizes why Swain and Macon should not be deemed connected.

NC 128 follows the Little Tennessee River northward, and in Macon County is also known as the Bryson City Road.  The eastern continental divide is well into North Carolina - it isn't on the North Carolina-Tennessee border as you might expect.

[jimrtex]

Graham (Robbinsville) to Macon (Franklin)
The direct road is NC 143 and NC 128 which is 45 mi and spends 14 mi in Swain. The route does not pass through any urban areas and doesn't approach the Swain county seat (Bryson City), though it does follow part of the preferred route one would take to get there from Graham. Graham and Macon are contiguous and a US highway crosses the border. One can use the the aforementioned local Wayah Rd (it's one of the NC secondary roads), so it's locally connected. This failed both the jimrtex and muon2 criteria.

You are most of the way from Robbinsville to Bryson City before you turn and go south. This is the route to Swain County, even NC 128 continues south.

That's what I assumed based on your definition of direct route, though you didn't say how much of the initial portion must be in common. Presumably using a main road to get out of the originating town is not enough to be considered the initial portion. I imagined that you would apply something like 1/3 of the route, consistent with the (2)(b)(i).

Direct Route: A route is direct if:
    (1) it it is not circuitous; and
    (2)(a) it is entirely within the two terminating counties; or
        (b)(i) less than 1/3 route is within the intervening county (-ies); and
             (ii) the initial portion of the route would not form part of the quickest route to more than   
                  1/3 of the residents of the intervening county. This calculation should be done in both
                  directions.

We agree that it shouldn't count as a connection for different reasons. Does Torie want a different outcome?

The example I gave after the definition used the county line as the decision point.

So as you reached the Graham-Swain line, the question would be is this also the way to Swain County, and the answer would be yes.

But I just thought of an case where that might not be a good definition.  There is a road from A to B and A to C, that forks when it is barely into B, with forks heading towards both B and C.

So perhaps the condition should be a percentage of the route to the intervening county that is in common.

The Robbinsville-Franklin route used 23/30 of the Robbinsville-Bryson City route, and Franklin-Robbinsville incorporates 19/27 of the Franklin-Bryson City route.

I think that the NC 128 coming north from Macon County is the Bryson County Road settles the issue that it really the route from Macon to Swain, with US 74 overlaying the last bit of the trip to Bryson City. NC 28 has pieced together two pieces of north-south roads connected along US74.

A fly in the ointment is that Google recommends US 23 and US 74 between Franklin and Bryson City. This eastern loop is longer, but slightly faster.


Just musing.  If we were trying to draw whole-county legislative districts, would connectivity really matter?  Could we simply require a modest amount of adjacency, since simply limiting county splits is going to prevent much real gerrymandering?

[jimrtex]

I like Bing maps for its ability to drag not only the route, but also the start and end points. Bing also shows the county lines crossed along on the route. I used that to first find the route and distance from Robbinsville to Franklin, then I dragged the ends to the Swain county lines along the route to get that segment length.

I haven't dismissed the idea of local connection plus nicked direct connection as an alternative. I just want some specific language I can test both for whole county connections and when counties are chopped.

Here's where I think the Torie plan is at present, so correct me if I'm wrong.

Two counties are regionally connected if they are locally connected and have either

  A) a continuous path of numbered state highways between nodes completely within the two counties; or

  B) a continuous path of numbered state highways between nodes that includes a segment outside the two counties provided that the segment
    1) is on the most direct route between the nodes; and
    2) comprises no more than one third of the most direct route between the nodes; and
    3) passes through no Census-defined urban areas; and
    4) carries the same state or federal number on its length.

The northern terminous of NC 28 was at US 74. It was later routed northeastward to Bryson City and then north. That it carries the name Bryson City Road north from Franklin indicates this history.  The new route of NC 28 goes to Fontana Lake which is on the Swain-Graham border. There is another road needed to get from Robbinsville to



If you look at the actual border between the counties, there is nothing in the northwestern corner of Macon County. US 129 south of Robbinsville looks like it is heading to the border, but when it gets close, it turns west parallel to US 74 before getting to the Cherokee County line and then the Cherokee-Graham-Macon intersection.

[jimrtex]

Since this came up in the Florida senate trial, I got the actual census bureau classification.

Primary roads are generally divided, limited-access highways within the interstate highway system or under state management, and are distinguished by the presence of interchanges. These highways are accessible by ramps and may include some toll highways.

Secondary roads are main arteries, usually in the U.S. Highway, State Highway or County Highway system. These roads have one or more lanes of traffic in each direction, may or may not be divided, and usually have at-grade intersections with many other roads and driveways. They often have both a local name and a route number.

The census bureau provides a layer comprised of primary and secondary roads, which is what I have used in QGIS.

Local Neighborhood Road, Rural Road, City Street

Generally a paved non-arterial street, road, or byway that usually has a single lane of traffic in each direction. Roads in this feature class may be privately or publicly maintained. Scenic park roads would be included in this feature class, as would (depending on the region of the country) some unpaved roads.

There are also classifications for ramps, service roads (feeders), 4WD trails.

[jimrtex]

Are you telling me that Dave's utility has an inaccurate map here, or things have changed? Try going to mapquest, and type a request for directions from Robbinsville to Franklin, and tell me what you see. What I see is a route all along highway 28. Unfortunately, photobucket won't upload the screen shot of that at the moment.

I really don't give a hoot whether my metrics make the two counties adequately adjacent or not of course. It is a very marginal case, that just slipped under the wire because of the elongated shape of Swain, and the fact that it is rural, and the highway happens to have the same number while traversing through Swain, and in this case, for its entire route between nodes (although that second bit is not required by my metrics).

That "secondary road" list has some potential, but for my allowing counties to be connected with non state highways, such secondary roads may still be too erose a path, with one having to make right angle turns from one road to another to get from one node to another (it's just really not designed as attempting to effect the practicable path between nodes - it's designed to service local rural areas). Thus my thought that we need to have a same numbered highway, which suggests some intent to try to create such a reasonably most practicable path.

A) 9 miles on NC 143 from Robbinsville to NC 28
B) 11.5 miles on NC 28 to US 74/19/NC 28.
C) 3 miles on shared designation US 28/74/NC 28
D) 21 miles on NC 28 to Franklin.

NC 28 goes northwest along the Swain-Graham line to Tennessee.  The big empty area in Swain County is Great Smokies National Park.

Segments A-B-C are generally eastward towards Bryson City. Segment D coming northward from Franklin is known locally as the Bryson City Road.

There is an excursion train from Bryson City to Andrews through the Nantahala Gorge, so the border between Graham and Macon is along the gorge. The reason NC 119 goes west is to find a bridge across the Nantahala River. So you are crossing a declivity to go directly from Graham to Macon.

Swain is north of Macon. Graham is at the extreme northwest corner of Macon.

I wasn't necessarily advocating for use of the primary and secondary roads. It was what I downloaded to use in QDIS. The alternative was "all roads" which includes streets. Perhaps the census bureau uses the primary and secondary roads when defining hops and jumps for urban areas.

But they were mentioned in the senate trial.

Already the judge has asked questions about: "standard deviation", "VTD", "shapefile, and "primary and secondary roads". If he would just hang out here, he would understand.

[jimrtex]

Washington is at once boring and interesting.  It’s boring because the map below (and while the possibility exists that the ever talented Muon2 might manage to draw a higher scoring map, in this case I don’t think so) causes absolutely no partisan change whatsoever from the existing map. It’s 4D, 2d, 1e, 1r, 2R, just like the existing map.  It has a Dem SKEW of 1.  And because of the interesting part, I am putting this post on the Muon2 policy oriented thread, rather than my partisan impact thread.



The map almost ended up with a higher Dem skew. My penultimate effort, had a chop into Gray’s Harbor County, rather than Thurston County because I have a bias against chopping into urban counties. But it could not be drawn without an extra state highway cut, as the highway in Gray’s Harbor went into and out of the adjacent CD.  So the final map which chopped into Thurston was the superior map avoiding one state highway cut, and the cut there pushed WA-03 over the line from tossup into the lean Pub category. My penultimate map is below.



I tried doing a Muon2 special, to wit, incurring a pack penalty to avoid an extra macrochop (into Pierce County), but alas that map was a fail, with two extra chops incurred as the cost of making the trade.  Perhaps the map would still be on the pareto optimal frontier due to avoiding a bunch of road cuts in Pierce County.  Here is the Muon2 special map:



Also notice that chop in Okanogan County in the map above. The road connection across the Cascades  is through the chopped county of Okanogan (in fact that is why it is chopped – the population numbers don’t otherwise require it, because while the chopped portion may have a lot of bears, it has very few people).  Is that allowed? It needs to be.

Another map that was a fail is below, but I put it up below to show a bridge chop in Yakima County. Again, I don’t see a problem with it, and if the population numbers had been just a tad different, the map might have ended up being best. In fact, Washington is so filled with blockades - mountain blockades, water blockades (San Juan must be appended to Skagit and so forth), county shape blockades (e.g. Callum County is nested in Jefferson County), population blockades (Yakima County plus Clark County have too much population to both be put in one CD), UCC blockades (it’s inconvenient that Douglas and Chelan are in one UCC, and ditto for Franklin and Benton), that absent bridge chops, the map might have ended up something of a disaster. But the population numbers worked – barely – to avoid such unpleasantness – this time.

 

Some folks are not going to like that a winning map causes a CD like the blue one (Reickert’s new district) to be drawn, from the Pacific Ocean, then a ferry crossing, then a bridge crossing, than a Cascades Mountain crossing, and then almost all the way to the Idaho border. What kind of community of interest is that? It sucks!

And the intra county road cut rules with respect to macrochops favor chops going into lightly populated areas, where fewer localities append each other. Thus the erose shape of my WA-09, as it deliberately makes a right angle turn to chop into Snohomish County.  It looks like a gerrymander to me. Blame Muon2 not me for that. I just play the game - I didn’t design it (well my fingerprints appear here and there, but whatever).  And again, the community of interest folks might howl. It tends to cause urban folks in one county to be combined with more rural folks in the adjacent chopped county. That will be something that is rather systematic, given the rules.

So, given the fact that there is absolutely no partisan change, the map must be similar to the map in place in Washington, right? Well, not exactly.  The map that was adopted was a Pub map, because a Dem commissioner voted for it – sort of a Mathismander in reverse. It was drawn to save Reichert’s butt, as his CD stays away from all those Democrats near the water in what is numbered as WA-08. WA-01 on the map looks similar, and did push that CD into a more marginal partisan status. Maybe the Dem commissioner was into SKEW minimalization or something.   And county chops seem to be preferred, rather than eschewed. That is what happens when folks start playing with communities of interest concepts I guess, or something.  And in this case, it ended up being a paradigmatic example of a lot of sound and fury signifying next to absolutely no change in partisan effect at all.

No year-round crossing of the Cascades into Okanogan.

[jimrtex]

Wait, is Yakima a UCC of its own? It's not colored on the stickied Jimrtex map.

Fixed.

[jimrtex]

The network map I posted was in my Atlas gallery that I found through a search. I created it in 2012 using Visio. It was for a thread about connections and regions in WA that had a lot of back and forth between jimrtex and I. Our differences about connections in NC can be visited in that thread three years ago. We really keep crossing the same ground on these issues, but I tend to resist wholesale thread necromancy so here we are.

Here is my Washington network map.  The fine red lines indicate adjacent counties, that I classified as unconnected. As usual, there are differences, between my definitions and Muon2's.



This is a version that might be presented to the public as part of a simple app for creating county combinations. The links are shown as traversing the boundary, and boundaries between adjacent but non-connected counties are shown as a barriers.



This is a district map with no chops.



This divides King County into 3 districts. IIRC, I used school district boundaries for the secondary division.



This adds a split of Pierce County to reduce deviation to a reasonable level.



This is a simplified county outline map showing multi-county UCC's and connected/unconnected status.

[jimrtex]

But I will get into that dealing with your King County map on that thread. On that map, did you count non state highway road cuts between municipalities in separate CD's that do not involve another county? I ask, because in general, the county chops are incentivized to go where fewer jurisdictions exist, which would tend to help the Dems because it is less populated areas that are chopped. In general, if one CD takes in the more rural areas, and the other CD takes in the populated areas, you will have one CD appending inside a county a ton of localities, with a lot of road cuts. Each and every road that leads out from a municipality to the balance of a county, even if there are no sub jurisdictions in the balance of the county, would count as a road cut. So that issue needs to be resolved first.

I'll reply over here.

The method I used to assess erosity in the King example was the one that was initially developed and applied in our exercise in AL and other states back in 2013. That only counted at most one connection between pieces of different districts within a county. We thought about applying townships in all cases, but an initial look at minor chops in OH showed that counting all the connections between townships/munis in a chopped county overly penalized those minor chops. However, something was needed to deal with dense counties like Cuyahoga where erosity could only be measured in terms of adjacent munis.

When we came to MI we dove into detail on when those connections between munis should apply. The preferred metric was to define a macrochop then apply the subunit connections only in those counties subject to a macrochop.

The essence of this erosity measure relies on having every parcel assigned to a division. For example every parcel in a state is in a county or equivalent so erosity at the county level makes sense. In MI every parcel in a county is in a township or muni so again the metric works appropriately. What we are trying to do is accommodate macrochopped counties in states where not every parcel is in a township/muni.

A big complication is that you only want subunits that reflect preexisting precinct lines. However, as I look at various state statutes I see it's usually the opposite from the direction that would work best for you. The precincts are updated to conform with political units after redistricting, not before. The policy reason is to reflect any new chops with new precinct lines.

In King there are munis but not every parcel is in one. I did not consider muni-muni erosity because I don't have a metric to define a connection when there is an unincorporated gap. For example there is an unincorporated gap between Kirkland and Bothell on my map. The gap was small enough that today they are contiguous, though they weren't in 2010. Either way, a meaningful erosity needs to assign that 2010 unincorporated area to a subunit.

Who wants to use precinct lines?  Torie, or a representative mapdrawer?

Why wouldn't it be better to expect that King County would define county subareas well in advance of the redistricting process?

[jimrtex]

Car rides are good for thinking, but less so for drawing, so this took a while. Here is a rule based way to create subunits, applied to King. These are the rules I used:

0. Municipalities and school districts are cut at county lines.

1. Each incorporated municipality is in its own subunit.

Consideration might be given to eliminating microcities, as well as treating city segments as separate.

2. Contiguous unincorporated areas in the same school district are in a single subunit. Precincts that overlap multiple districts are assigned to the district with the most voters in that precinct.

I don't understand the purpose of the assignment rule for splitting precincts. This appears to have been applied to the area between Auburn and Kent that is attached to the Lakeland portion of the Federal Way USD.

3. Incorporated municipalities entirely within an unincorporated subunit are merged.

What if they are substantially enclosed, or dominate the unincorporated area. For example why not merge the two unincorporated areas east of Federal Way, which are within Federal Way SD in a single Federal Way subunit.

Other possibilities are Milton + Fife SD, Auburn + eastern Auburn SD, Kent + northeastern Kent SD, Covington + southeastern Kent SD, Black Diamond + Enumclaw SD, Maple Valley + Tahoma SD, Renton SD, excluding areas in cities other than Renton, Issaquah SD, excluding areas in cities other than Issaquah, Redmond + eastern Lake Washington SD. Kirkland + northwestern Lake Washington SD.

4. Unincorporated subunits entirely within an incorporated municipality are merged.

5. Unincorporated subunits smaller than 0.5% of the quota are merged with an adjoining municipality in the same school district.

I ended up with 51 subunits shown below as a whole county and with detail on the western side. Colors are grouped by school district with darker shade for munis and lighter shades for unincorporated subunits. If this seems workable I can produce the connection map to use for erosity. I also have the populations of each of the subunits if they are of interest.

It may be useful to exclude large bodies of water from any subareas, and then fill them in after the map is drawn. There is inconsistent annexation of Puget Sound and Lake Washington.

0. Cut cities and school districts at county lines. Exclude large bodies of water (eg Puget Sound and Lake Washington). Areas will continue to be connected by bridges and ferries. The water area can be added back after the district is assembled.

1. Associate cities with school districts. A city is associated with a school district if 80% or more of the city's population is in the school district. Adjust the school district boundaries to include all of any associated cities. If a city is not associated with a school district (eg Sammamish?), treat it as if it were its own school district.

2. Treat small cities as if they are unincorporated for purposes of forming subunits. A small city has less population than the lesser of (5,000 or 5% of the county population). For King County,

Algona, Beaux Arts Village, Black Diamond, Carnation, Clyde Hill, Hunts Point, Medina, Milton, Skykomish, and Yarrow Point are small cities.

Rule 1 is applied before Rule 2. While a small city may not form a subunit, it will be entirely within a subunit.

3. Treat each adjusted school district as a subunit.

[jimrtex]

Those are some useful suggestions, jimrtex.

The one I'd quibble most with is associating non-small cities with school districts. One issue is it would lead to fewer and substantially larger subunits. The second issue is that many of the incorporated cities did so to have a clear identity apart from the school district. An example of this is Lake Forest Park which incorporated in 1961 from unincorporated Shoreline. Shoreline only incorporated the western part of the school district in 1995.

The small city merger raises a parallel question to one we faced in the Detroit metro. In Oakland county there were a number of small communities around Royal Oak. This allowed a plan to avoid muni chops but at the expense of erosity. If states like WA merged them away, they lose the type of trade off available in MI.

In King County, at least, there is a strong relationship between cities and school districts. This may reflect the pattern of school district consolidation. The original districts had to be within walking or riding distance of the school, and may have only offered 6 or 8 grades of school. School districts might have been based in part on the public school survey system since there was the school section in each survey township. In Washington, this would have been adjusted based on terrain, but it probably was used in places like Lincoln and Adams counties.

There might only be high schools in towns. A promising student from a rural area might board to attend high school. During consolidation, you would want enough students to support a high school, and within busing distance. So consolidated districts would be based around a town, and the surrounding less populated hinterland.

School districts can be considered the equivalent of an organic township formation.

And considering that Seattle is a subunit, it does not make to have subunits that are less than1% that size.

The utility of the Royal Oaks area, should be considered a happenstance, and not necessarily something to be recreated. If you go further out from Detroit, the cities tend to take in the entire township.

The cities of Shoreline and Lake Forest could be tertiary subunits of the adjusted shoreline district.

[jimrtex]

I had some questions I laid out about the subunit rules that I set out, mostly out of confusion. I don't know what the Jimrtex zero rule is. Where to put bodies of water? Who cares? We don't want to generate a chop over areas with no population anyway. I am skeptical about erasing small cities. There had better be a good reason for that. Otherwise, they might feel picked upon. And it does give more guidance as to where precise lines should be drawn. I grant that it does not involve skew issues.

Any county really that is subject to a macrochop in end should be mapped out, not what our maps happen to chop up. Granted, Spokane is not subject to chop, and never will be, at least for CD maps. Clarke county might be subject to macrochop. I still want to know when city neighborhoods need to be mapped out. When they are subject to macrochop?

You probably did not notice, but school districts and cities can cross county lines in Washington, and they do in King County. Since subunits must nest, there are three ways to handle this:

(1) Chop cities and towns at county boundaries.

Pro: Simple.
Con: May produce micro-units if a city merely laps across the boundary.

(2) Adjust county boundaries, to match city boundaries that cross county lines.

Pro: Better reflects COI based on cities.
Con: Makes county boundaries irregular. May divide county-based COI, and might disrupt county-based election administration.

(3) Permit cities that cross-county boundaries to be considered as being in both (or more) counties, or in the individual counties.

Pro: Gives more discretion to the mapdrawer.
Con: Can be gamed, since it effectively creates two micro-counties where a city crosses a county boundary.

On Muon's map, there were subunits in Puget Sound, offshore Federal Way and Des Moines, but not offshore Normandy Park and Berien, because those two cities have annexed the area in the water. The same thing happens along Lake Washington.

Including these areas creates contiguity, and may foster an impression of connected, for example in this case, with Vashon Island, which should only connect based on the ferry (and the ferry landing).

In Florida, the area within the 3-mile limit is included in their maps, and within their compactness scores. It is gamed, along with the Everglades.

[jimrtex]

On Muon's map, there were subunits in Puget Sound, offshore Federal Way and Des Moines, but not offshore Normandy Park and Berien, because those two cities have annexed the area in the water. The same thing happens along Lake Washington.

Including these areas creates contiguity, and may foster an impression of connected, for example in this case, with Vashon Island, which should only connect based on the ferry (and the ferry landing).

In Florida, the area within the 3-mile limit is included in their maps, and within their compactness scores. It is gamed, along with the Everglades.

This one confuses me some. We don't do compactness. We require bridge or ferry connections. If we have an instance where municipal water surrounds an area not within the municipality, and that area not within the municipality has adequate connections to another CD, I am leery of using the water to merge that water surrounded area to the municipality, but on this one my views are more tentative.

Erosity is a compactness measurement.

The judge in Florida just approved a plan that used the Everglades to bypass population.

[jimrtex]

On Muon's map, there were subunits in Puget Sound, offshore Federal Way and Des Moines, but not offshore Normandy Park and Berien, because those two cities have annexed the area in the water. The same thing happens along Lake Washington.

Including these areas creates contiguity, and may foster an impression of connected, for example in this case, with Vashon Island, which should only connect based on the ferry (and the ferry landing).

In Florida, the area within the 3-mile limit is included in their maps, and within their compactness scores. It is gamed, along with the Everglades.

This one confuses me some. We don't do compactness. We require bridge or ferry connections. If we have an instance where municipal water surrounds an area not within the municipality, and that area not within the municipality has adequate connections to another CD, I am leery of using the water to merge that water surrounded area to the municipality, but on this one my views are more tentative.

Erosity is a compactness measurement.

The judge in Florida just approved a plan that used the Everglades to bypass population.

Yes, but we don't use it. It is one of several advantages of using the highway cut proxy as a measurement of erosity. It allows for benign rather than partisan erosity - erosity that is really not about people, but geographic obstacles, or county lines which themselves are erose.

How would you define subunits in Miami-Dade County?

I also think you are too narrowly tied to a particular methodology.

How would you in general define nested sets of units that districts may be composed of?

[jimrtex]

Here's my division of central King.



Note that the incorporated town of Beaux Arts Village is surrounded by Bellevue and was merged into it along with some unincorporated inclusions for tot pop 128192. Shown on the northern map the other small communities of Clyde Hill (2,984), Hunts Point (394), Medina (2,969), and Yarrow Point (1001) were not included since they are not surrounded by Bellevue. It's similar to the Sylvan Lake-Keego Harbor-Orchard Lake Village triad in Oakland county MI.

Beau Arts Village is not surrounded by Bellevue. It's western border is in the unincorporated portion of the Mercer Island school district.

[jimrtex]

Here's the high-contrast detail for SW King.



The Eunumclaw school district includes the cities of Black Diamond (4151) and Eunumclaw. The unincorporated part of the school district completely surrounds Eunumclaw but not Black Diamond, so  Eunumclaw is merged with the unincorporated area for a total of 23296 residents (red-orange precincts).

Enumclaw (note spelling) has some exclaves, including one that straddles the Pierce-King line. Does that mean the school district doesn't enclose Enumclaw.

[jimrtex]

Based on a threshold of 80%, only Black Diamond, Sammamish, and Newcastle would not be associated with a school district.

This would produce 20 subunits associated with school districts, and three that would be associated with cities. If the adjusted school districts were used, then a tertiary division could use both cities and CDP's. Only 56,000 residents live outside census places.

If the threshold were increased to 90%, Bellevue, Des Moines, and Kent would fail, and if it were increased to 95%, Auburn, Renton, and Tukwila would not qualify. Since 5 of these 6 districts share the name of a city, this would indicate that 80% is a reasonable threshold, and 90% may be too high.

At is almost universal that there are a few stragglers, suggesting that the districts are based on cities, which have subsequently annexed areas after school consolidation. The cities that span districts are further east, and likely reflect that their establishment (or growth) occurred after the districts were created.

There are about 800 persons outside Seattle in the Seattle school district, and a handful of Seattle residents outside the school district.

[jimrtex]

Beaux Arts Village is contiguous to Mercer Island, but not connected due to Lake Washington. Since the only connection is to Bellevue, it is surrounded.

Is this different than Asotin or San Juan counties?

If Bellevue was chopped, could I dice Beaux Arts Village as part of the chop?

[jimrtex]

The second column is the population of each school district (within King County)

The third column reflects inclusion of the entirety of a city in the school district which is the predominate district. For example, Auburn school district adds the portions of the city of Auburn that are in the Federal Way and Kent school districts, plus the portion of the city of Pacific in Fife school district.

Federal Way and Issaquah school districts lose the most to this adjustment, with Federal Way losing to the cities of Kent, Des Moines, and Auburn; while Issaquah loses mainly to the city of Bellevue.

The fourth column is adjust to treat the cities that are divided among several districts as separate subunits.

Black Diamond is about 60% in Enumclaw district, with the remainder in Kent and Tahoma.
Newcastle is about evenly split between Renton and Issaquah.
Sammamish is about evenly split between Lake Washington and Issaquah.

These three cities are further east, with growth after the school districts had been delineated.

Auburn School District   77609   81444   81431
Bellevue School District   124003   134166   134123
Enumclaw School District   25179   25179   22708
Federal Way School District   130706   111023   111023
Fife Public Schools   4302   4058   4058
Highline School District   124481   127691   127691
Issaquah School District   98660   86439   60477
Kent School District   158233   168732   167727
Lake Washington School District   177476   178289   153417
Mercer Island School District   22699   22699   22699
Northshore School District   76338   76304   76304
Renton School District   115511   117924   112850
Riverview School District   19315   19315   19315
Seattle School District   609471   609060   609060
Shoreline School District   65547   65605   65605
Skykomish School District   627   627   627
Snoqualmie Valley School District   35054   35054   34845
Tahoma School District   37376   37516   36854
Tukwila School District   18038   19500   19500
Vashon Island School District   10624   10624   10624
Black Diamond city   0   0   4151
Newcastle city   0   0   10380
Sammamish city   0   0   45780

[jimrtex]

The subunits of a city are its precincts? What does that mean? That seems to imply there would never be a chop. When does a city have neighborhoods larger than single precincts?

I was quoting the rule we adopted for MI last year. We decided that we would only define neighborhoods for Detroit, since it had to be chopped. No one raised the issue of neighborhoods for the other communities, so we defined precincts as the subunits for computing erosity had the situation occurred. It's in the thread I linked.

The MI rules implied that cities that must be chopped would have defined neighborhoods, but we never addressed what if any other cities would have neighborhoods.

Is it your intent that units would also be used for legislative redistricting?

[jimrtex]

Beaux Arts Village is contiguous to Mercer Island, but not connected due to Lake Washington. Since the only connection is to Bellevue, it is surrounded.

Is this different than Asotin or San Juan counties?

If Bellevue was chopped, could I dice Beaux Arts Village as part of the chop?

When I'm shifting counties to form regions I treat Asotin and Garfield as a single unit. Any shift of Garfield brings Asotin along with it, since Asotin is only connected to Garfield. A bigger example is the UP of MI which stays together with Cheboygan for CDs since it has only that one connection.

Bellevue is large enough to macrochop so it's conceivable that neighborhoods could be defined, and Beaux Arts Village would be a neighborhood. If we treat Bellevue as we did other large cities in MI (except Detroit), then the subunits of the city are the precincts and Beaux Arts Village is its own precinct, so it would not be chopped.

If the rule set forces Beaux Arts Village to be included in a district that includes Bellevue, there is no reason to do a formal merging. You have similar situations in Idaho, Minnesota, New York, Florida, and Texas with counties and probably others.