
Gerrymandering and a cure for it – the shortest splitline algorithm - clukic
http://rangevoting.org/GerryExec.html
======
tunesmith
Isn't gerrymandering a much more complex problem than that makes it out to be?
I've always thought the problem was that it's actually difficult to even come
up with a definition of what fair is. For instance, do you want each district
to be as representative of the population as possible? Or do you want the
house of representatives to be as representative of the population as
possible? I suspect that you can't have both. For instance, if you have a
state that is 60/40, then do you want each district to be 60/40? Or if it has
ten representatives/districts, do you want 6 reps of one party and 4 of the
other? What is districting even supposed to aim for? I don't think there is
one reasonable answer to this question, which is why I think any attempt to
answer this question for all states is doomed to fail.

The only way I can think of to get both is to increase the number of
representatives. The House of Representatives was originally supposed to scale
with the size of the population, and they eventually put a stop to that. If
they had continued, then we'd have a house with a makeup that matches national
polling much more closely than it does now, and gerrymandering wouldn't be as
much of a problem. Isn't it true that as you add more representatives,
gerrymandering distortions lessen?

~~~
dragonwriter
> Isn't gerrymandering a much more complex problem than that makes it out to
> be?

No, its vastly simpler: the problem with gerrymandering is that there is _no_
good way to draw single-member winner-take-all districts, and the solution is
just _don 't do that_. Multimember districts with a system that provides
proportional representation within each district (e.g., five-member districts
with STV) solve the problem pretty much completely.

Algorithmic line-drawing of single-member winner-take-all district pretty much
guarantees poorly-representative districts, but without anyone being able to
control how and where they are bad (well, except that there are quite a lot of
algorithms that can be chosen, so the political choice of _which_ to choose
will be influenced by the effect the particular algorithm would have on the
particular jurisdiction adopting it.)

~~~
specialist
Agreed.

But even when the USA sees the light on proportional representation, there
will continue to be winner takes all elections. Executive positions
(president, governor, mayor), senators, judges, ballot issues, etc.

In those cases, approval voting is the correct answer. Easy to explain, easy
to tabulate, most mathematically fair, hardest to game.

Per Duvenger's Law, approval voting would probably also help replace the
current two party system with more choices.

~~~
Turing_Machine
"But even when the USA sees the light on proportional representation"

"Sees the light"? Proportional representation is far from a panacea. It tends
to lead to a fragmented government (which is usually bad). It also privileges
party over individual candidates (which can be good or bad, but those who
dislike partisanship would certainly disapprove). There are other factors at
play as well.

Most (in)famously, the Weimar Republic used PR. That didn't end well.

~~~
dragonwriter
> Proportional representation is far from a panacea.

Among modern, established democracies, proportionality of representation is
pretty closely linked to public satisfaction with government, and public
participation with government. Its as close to a panacea for effective
democracy as you could have -- which isn't surprising, proportionality of
representation is a pretty direct measure of the extent to which a government
_is_ democratic.

> It tends to lead to a fragmented government (which is usually bad).

Any government in a system with a diversity of viewpoints is either going to
be minoritarian or coalition based; winner take all tends to majority-of-a-
majority -- which can be minoritarian -- and, whether it is that or not, tends
also to involve non-overt coalition building in structuring big-tent parties.
PR systems tend to be more likely to be actually majoritarian, and tend to
feature _explicit_ \-- and thus more accountable -- coalition building. It
doesn't lead to "fragmented" government by any meaningful measures.

Itssometimes portrayed as leading to less _stable_ government, because in
parliamentary systems its associated with more rapid turnover of government
administrations/cabinets, but by another measure, it leads to _more_ stable
government, as while there is more frequent turnover of cabinets, there is
more continuity between successive governments/cabinets, and more continuity
in governments/cabinets over time.

> It also privileges party over individual candidates (which can be good or
> bad, but those who dislike partisanship would certainly disapprove).

Certain methods of achieving proportionality (e.g., party list systems) may do
so; candidate-centered election methods with rules that produce proportional
results (like single transferrable vote in small multimember districts) do
not. In fact, such systems would do the opposite compared to the status quo
system in the US, emphasizing individual candidates over party by offering
more competition, even in general elections, between individual candidates
even in districts with a clear majority for a single party.

> Most (in)famously, the Weimar Republic used PR. That didn't end well.

Constitutional provisions for Presidential rule-by-decree had a lot to do with
that, PR -- or even the particular form of PR used by the Weimar Republic --
well, if you want to argue that that was responsible for something, then go
ahead and make that argument.

~~~
Turing_Machine
"Among modern, established democracies, proportionality of representation is
pretty closely linked to public satisfaction with government"

When one of these "modern, established democracies" manages to maintain a
stable government (or even survive) for as long as the United States has,
perhaps that statement could be made.

[https://en.wikipedia.org/wiki/Proportional_representation#Li...](https://en.wikipedia.org/wiki/Proportional_representation#List_of_countries_using_proportional_representation)

Other than perhaps the Scandinavian countries, that's not exactly a list that
makes one optimistic about stability.

Edit: "Constitutional provisions for Presidential rule-by-decree had a lot to
do with that, PR -- or even the particular form of PR used by the Weimar
Republic -- well, if you want to argue that that was responsible for
something, then go ahead and make that argument."

See my response to the other poster below. The PR system (and the myriad of
squabbling parties produced by it) led to there being no effective government
for two subsequent parliamentary elections.

~~~
samfoo
Of the top twenty most developed countries in the world (ranked by HDI), over
half (13) have some form of proportional representation. They aren't all
Scandinavian countries, though predictably many are. Which of them would you
not consider a stable government?

    
    
        Y    Norway 
        Y    Australia 
        Y    Switzerland 
        Y    Netherlands 
             United States
        Y    Germany 
        Y    New Zealand 
             Canada 
             Singapore 
        Y    Denmark 
        Y    Ireland 
        Y    Sweden 
        Y    Iceland 
             United Kingdom
        Y    Hong Kong 
             South Korea 
             Japan 
        Y    Liechtenstein
        Y    Israel 
             France

~~~
mseebach
Correlation isn't causation. The best conclusion you can draw from your list
is that _neither_ PR or FPTP inherently _hampers_ development.

> Which of them would you not consider a stable government?

Whoa, that's some strawman. The standard we're looking to prove is
"proportionality of representation is pretty closely linked to public
satisfaction with government".

~~~
icebraining
_> Which of them would you not consider a stable government?_

 _Whoa, that 's some strawman._

No. The person who was being replied to specifically wrote about stability.

------
specialist
The goal isn't pretty lines.

The goal is maximal competitiveness. Which boosts voter participation. Which
gives legitimacy to the results.

[https://en.wikipedia.org/wiki/California_Citizens_Redistrict...](https://en.wikipedia.org/wiki/California_Citizens_Redistricting_Commission)

 _" While the long-term results will bear out over time, independent studies
by the Public Policy Institute of California, the National Journal, and
Ballotpedia have shown that California now has some of the most competitive
districts in the nation, creating opportunities for new elected
officials.[12][13][14]"_

~~~
ClayShentrup
Independent redistricting commissions don't work.

[http://scorevoting.net/GerryComm.html](http://scorevoting.net/GerryComm.html)

~~~
caf
Apparently they don't work _in the US_.

That link says that they work in Canada, and they work in Australia too.

Without an underlying reason identified, this conclusion is somewhat
unsatisfying.

~~~
Frondo
The link also gives unsatisfying reasons for _why_ it says they don't work,
e.g. incumbents keep winning elections.

I haven't studied the matter really closely, but from what little I do know of
the issue, it makes me wonder--are Arizona, Washington, and NJ examples of the
hyper-gerrymandered states that citizen redistricting is supposed to prevent?

Could it be that, in those states, they're already starting out from a pretty
equitable district layout, such that when the citizenry gets to redraw the
layout, it doesn't actually matter much?

Or, put another way, how would a citizen redistricting panel work in Florida
or North Carolina or Texas?

------
JDDunn9
Gerrymandering gets attention because it is malicious misrepresentation, but
unintentional misrepresentation is just as bad. Voting is a flawed system that
will always give some voters more voice than others.

\- The people who voted for the loser will not be represented (one of the
reasons minorities are underrepresented).

\- The need of local representation is illusory. Make a list of all the
political issues you care about. How many of them are local?

\- The effect of a bi-cameral legislature means that in the Senate, voters in
Wyoming have over 60x the voting power of voters in California.

\- Voting itself is irrational under a cost/benefit analysis. So by
definition, the least rational citizens are picking candidates.

\- Name recognition is huge for elections, meaning money will always effect
elections.

\- Candidates suffer self-selection bias (as well as others). To run, you need
to be good at public speaking (fear of public speaking is one of the most
common fear in America), look a certain way (no tattoos or piercings allowed),
and have a lust for power.

Representation is a math problem. The only solution is random sampling.
Replace Congress with 1 house made up of 1,000 randomly sampled citizens and
we will have true representation.

~~~
panglott
You'd get a good sample, but a poor representative. If a group of people is
attempting to choose a person to advocate their interests, they'll choose the
person best at advocacy, who is likely atypical in a variety of ways.

Because typically people are bad at public speaking, rhetoric, bargaining, and
other means of advocating their interests.

~~~
JDDunn9
Not everyone has to address Congress. As long as each valid viewpoint has at
least one advocate, I trust people could figure out the best option. Less
bargaining means fewer riders and pork, which is a good thing. I'm fine if
only the best ~10% of Congress wrote/debated laws and the rest simply voted.

Also, remember we are comparing against the current Congress, which only
represents the wealthiest among us. Pretty low bar.

------
kevinoid
This is an elegant solution with a lot of good properties: Equal population
balancing, politically unbiased, reasonably understandable by the layman,
typically geographically compact districts. But where's the discussion of the
desirable and undesirable properties in a districting algorithm and how this
algorithm achieves or doesn't achieve these properties?

specialist already mentioned maximal competetiveness, ROFISH mentioned
clustering due to natural features. Is regional or ethnic representation
important, or is it an undesirable bias? How about travel distance (either for
voters or campaigners)? I'm sure you guys can think of others you'd like to
see or to avoid. Feel free to suggest some, I'm curious.

There is a little more information at
[http://rangevoting.org/SplitLR.html](http://rangevoting.org/SplitLR.html) but
did I miss the real weighing of the tradeoffs and advocacy for this particular
method above all others?

Edit: Found a discussion of the theoretical issues at
[http://rangevoting.org/TheorDistrict.html](http://rangevoting.org/TheorDistrict.html)
which touches on some, but not all of the points raised.

------
username223
This is no more a cure for gerrymandering than Condorcet voting is a cure for
the various ills of the two-party system. Until you have a plan to implement
this algorithm in the current political system, you're just solving sudokus
and crosswords.

------
chasing
The problem with gerrymandering isn't that people aren't capable of drawing
simple lines to split states into districts.

~~~
eru
Oh, but this algorithms removes all the choice. So there's nothing up anyone's
sleeves.

~~~
tfinniga
It just moves the problem.

Instead of arguing about the borders, you have arguments about which
clustering algorithm to use, and what the weights to the inputs should be.

A simplistic algorithm like shortest splitline will give impractical results
in many cases. For sure you're going to put Eagleton and Pawnee in the same
district.

Unless you have a mathematical definition of districts that lead to good
government, a purely mathematical solution won't be possible.

~~~
eru
> Instead of arguing about the borders, you have arguments about which
> clustering algorithm to use, and what the weights to the inputs should be.

Yes, that's true. But with any luck the weights will have less knobs to turn,
ie less information, than drawing lines.

> Unless you have a mathematical definition of districts that lead to good
> government, a purely mathematical solution won't be possible.

We just need to avoid the worst government.

Or perhaps the Americans can just look around the world to see how other
countries are drawing their voting districts, and compare what works and what
doesn't. (Shouldn't federalisms make that kind of experimenting work inside
the US alone, too?)

In any case, there's a more interesting simple technocratic fix to try: count
ballot papers that tick more than one candidate as a vote for each of the
ticked candidates.

This way you can vote for the lesser evil and who you actually want.

(See
[https://en.wikipedia.org/wiki/Approval_voting](https://en.wikipedia.org/wiki/Approval_voting))

------
brianolson
Here's a better algorithmic non-gerrymandered districting, solving for
compactness: [http://bdistricting.com/2010/](http://bdistricting.com/2010/)

------
onewaystreet
Gerrymandering is an intentional act carried out by politicians, not one of
happenstance. It's not something that can be cured with algorithms.

~~~
gjm11
I take it the proposal is that there should be a law requiring that such-and-
such an algorithm be used. That would take away the politicians' power to
gerrymander.

(Of course it would also need to be voted for by the same politicians who
presumably won by gerrymandering. Good luck with that.)

------
statenjason
The Redistricting Game[1] is an interesting approach to teaching about how
gerrymandering works.

[1]:
[http://redistrictinggame.org/game/launchgame.php](http://redistrictinggame.org/game/launchgame.php)

------
CWuestefeld
I'm concerned with the stability of the district borders. Because of the way
this algorithm seems to like to slice through cities, it seems like minor
changes in neighborhood density of a city is likely to significantly change
the angle of the bisecting line, thus shifting large areas of the outlying
region from one district to another.

This is bad for two reasons.

First, it seems a big weakness of democracy is voter ignorance. Throwing
people repeatedly from one district to another, so they don't have time to
learn the issues relevant to their district and the record of their
representatives, will exacerbate the problem.

Second, the system can be gamed. It looks to me like approving or denying the
construction of a large apartment complex near the center of a city can be
used as a tool to push lines one direction or another. So approving that big
apartment building in the city will increase population in that region,
tending to tighten the angle made around it, thus freeing some voters from
that district and pushing them into a neighboring one. Indeed, since the
algorithm is recursive, this could have big follow-on effects subsequent
iterations.

------
ROFISH
One problem with this: it makes sense that district lines could be along
natural (rivers, lakes, mountains) or political (towns, county) lines.
Trusting a simple line algorithm may bisect a town down the middle.

~~~
cjensen
Yep. Consider Eastern California: the Sierra Nevada runs north to south
creating a natural barrier. There's a small sequence of cities east of the
barrier. During the Spring and Fall campaign season, it can be literally
impossible to cross that barrier: you must go a long way around or fly.

The suggested algorithm would unite cities on both sides of the divide. It
would be very difficult for an underfunded candidate to campaign on both
sides.

------
DennisP
A while back, I was friends with someone who was a forensic accountant and
former state senator. She talked about gerrymandering quite a bit. She'd say
"you don't choose your representatives, they choose you."

She said both parties cooperated in drawing safe seats for everybody, and
claimed that most of the people in our state congress were corrupt. Anyone who
didn't play along with the graft would find their district redrawn out from
under them, if the timing made that possible.

This actually happened to another friend who was a former state house member.
The two of them were instrumental in revealing the corrupt activities of state
House Speaker Jim Black, who ended up serving time in prison.

~~~
JoeAltmaier
I imagine Jim Black was a sacrifice as well - he didn't play along with
somebody, so he got tossed to the wolves. And the public thinks "Well, that's
been dealt with" and the rest of the corrupt remain safe from further
scrutiny. For a while.

------
kevinpet
I think this is fascinating even if it will never happen. It's important to
keep in mind the nominal and actual result of human drawn district boundaries
("gerrymandering" is a pejorative).

In theory, human drawn district boundaries can create districts which are more
homogenous so that, for example, a state with a few representatives and a few
defined geographic or political divisions can divide things up in a way that
makes sense. For example, it would seem odd for Las Vegas to be split into
multiple districts in vast barren Nevada (it isn't -- LV is the smallest
district).

What happens in practice is: "Contrary to one popular misconception about the
practice, the point of gerrymandering isn't to draw yourself a collection of
overwhelmingly safe seats. Rather, it's to give your opponents a small number
of safe seats, while drawing yourself a larger number of seats that are not
quite as safe, but that you can expect to win comfortably."
[http://www.washingtonpost.com/news/wonkblog/wp/2014/05/15/am...](http://www.washingtonpost.com/news/wonkblog/wp/2014/05/15/americas-
most-gerrymandered-congressional-districts/)

~~~
vezzy-fnord
_Contrary to one popular misconception about the practice, the point of
gerrymandering isn 't to draw yourself a collection of overwhelmingly safe
seats. Rather, it's to give your opponents a small number of safe seats, while
drawing yourself a larger number of seats that are not quite as safe, but that
you can expect to win comfortably._

That almost sounds like a tautology.

~~~
chadzawistowski
What's tautological about it?

Here's the same sentiment expressed in image form:
[http://i.imgur.com/bRPcQ7O.jpg](http://i.imgur.com/bRPcQ7O.jpg)

~~~
vezzy-fnord
In the original statement, the latter is just a slightly more detailed
strategy for achieving the former.

~~~
bjterry
I think the ideal strategy in gerrymandering is not immediately obvious
(although it may technically be a tautology, it is not obviously
tautological). If you asked people which of the two following strategies is
ideal, many would give the wrong answer:

1\. Begin by drawing the districts such that your opponents win almost 100% of
the votes in as many districts as possible.

2\. Begin by drawing the districts such that you win almost 100% of the votes
in as many districts as possible.

Upon analysis the mathematics of the situation is obvious, but one's gut
reaction may be that winning elections handily for yourself seems obviously
good.

------
peter303
Splitline doesnt honor community or geographic boundaries. I'd suggest a
modification that honors zipcode boundaries. The USPS has figured out basic
units already.

~~~
saalweachter
Fun fact: there is actually no such thing as ZIP code boundaries.

ZIP codes are actually based on delivery routes: your ZIP code is the post
office your mail carrier leaves from. ZIP codes will not actually respect
community boundaries: if a town lies between two post offices, it is
frequently more efficient for mail to be delivered by carriers from multiple
post offices.

Moreover, not every address in the US receives home delivery. If the post
office does not have a delivery route going past your home address, you can
instead get a post office box from whichever post office you find most
convenient. What happens to packages addressed to those street addresses is
... complex.

The "ZIP code maps" you have probably seen are actually creations of third-
parties. If you ask very nicely, the Post Office will give you a list of which
street addresses belong to which ZIP codes. A couple of different third party
map-makers will then try to create a map based on these lists. They are not
always useful or accurate.

~~~
JoeAltmaier
Ok I wondered about this. Our local village has no mail delivery; everybody in
town has to have a PO box. I thought Federal mail delivery was a given thing,
like a right. How can the town just decide to blow it off?

~~~
saalweachter
Home delivery was never quite universal. Rural Free Delivery
([https://en.wikipedia.org/wiki/Rural_Free_Delivery](https://en.wikipedia.org/wiki/Rural_Free_Delivery))
wasn't even a thing until the 1890s. Hilariously, with budget cuts, there has
been more of a tendency to keep RFD while cutting home delivery in some of the
smaller towns and villages, since it is easier for people in the village to
get to the post office.

------
mudetroit
It is pretty... but vastly oversimplifies the problem. If we are ever going to
get something for real it needs to take into account real problems. Talking
about things like actual operation of elections, not producing high numbers of
different ballots because of splitting of districts.

For something to really work it is going to need to take into account things
like existing political, and probably some physical, boundaries.

------
tomohawk
I'd love to get rid of gerrymandering. I live in a massively gerrymandered
district where the representative can very safely ignore the area where I
live.

This algorithm appears to have some interesting results though. Check out
Maryland:
[http://rangevoting.org/Splitline2009/md.png](http://rangevoting.org/Splitline2009/md.png)

~~~
dhimes
(O/T) And I live in the town where Gerry was from (his name is pronounced with
a hard-G by the way, like Gail, not Jerry).

We have a drinking club named after him!

[https://en.wikipedia.org/wiki/Elbridge_Gerry](https://en.wikipedia.org/wiki/Elbridge_Gerry)

------
cschmidt
That seems to be a very oversimple approach. Cities are the most obvious
problem. You kind of want a population center to have a single congressmen
representing it. Mathematically, you want districts to be fairly compact.
There have a been several Operations Research papers that try to do things in
a more practical way.

Also, a greedy approach (split in half, repeat) seems weird to me.

------
asmithmd1
Technology can be used to help with this problem. Take a look at the maps from
CommonCensus:

[http://commoncensus.org/maps.php#local_maps](http://commoncensus.org/maps.php#local_maps)

First people "vote" for the boundaries of their neighborhood and then
congressional districts are created using these neighborhoods as atomic.

------
orik
The author of this site seems to think that in the ideal world, districts
would be decided up with clear straight lines.

This is not the case. Districts should represent distinct groups of people.
Ideally, with well drawn districts, political representation will be accurate
to the popular vote.

I'd recommend you all read the following article if you haven't yet.

I think if you wanted to solve districts algorithmically, you would need a
neural network.

[http://www.washingtonpost.com/news/wonkblog/wp/2015/03/01/th...](http://www.washingtonpost.com/news/wonkblog/wp/2015/03/01/this-
is-the-best-explanation-of-gerrymandering-you-will-ever-see/)

------
thephyber
Similar to this other algo:

[http://bdistricting.com/2010/](http://bdistricting.com/2010/)

------
wahsd
Although I don't necessarily disagree with this concept, I am not sure it is
well refined. I noticed, looking at a certain city, that even with this
shortest splitline the city was still rather split by more or less ethnically
demographic lines.

------
Glyptodon
Another more obvious solution is to get rid of congressional districts and
then apportion the seats down the list of highest vote getters to lowest vote
getters until there are no more seats (across the entire state).

------
cmatt85
[https://www.youtube.com/watch?v=kUS9uvYyn3A](https://www.youtube.com/watch?v=kUS9uvYyn3A)

this explains it quite well.

------
EGreg
Gerrymandering has more to do with Simpson's paradox. Look it up :)

~~~
bru_
Dude... thank you

------
cmatt85
This describes it quite well.

------
a8da6b0c91d
Doesn't gerrymandering mostly carve out a lot of districts for black
congressmen who otherwise wouldn't have districts? I think that's kinda what
it boils down to in America. There are conservative areas adjacent to and
mixed with majority black areas and they want different representation.

~~~
igonvalue
I'm not sure how common it is, but the linked site actually has an interesting
discussion of this phenomenon, which Wikipedia calls "affirmative racial
gerrymandering"[0], and how it would interact with the proposed scheme:
[http://scorevoting.net/TheorDistrict.html#Minority](http://scorevoting.net/TheorDistrict.html#Minority)

[0]
[https://en.wikipedia.org/wiki/Gerrymandering_in_the_United_S...](https://en.wikipedia.org/wiki/Gerrymandering_in_the_United_States#Affirmative)

------
cryogospel
gerrymandering is good--for the electorate. why?

Because gerrymandering increases homogeneity. A gerrymandered district is more
homogeneous--the voters are more alike than they were before. In general.

Homogeneity in general increases unity. A more homogeneous district means the
voters in general share more common interests. If the voters share more common
interests then it is easier for them to elect and hold accountable a
politician who can represent their common interests.

Of course if you want the corporations to have more control over the
government, and you want the people to have less control, then gerrymandering
is indeed bad.

~~~
jkestner
Texas's 23rd stretched from Austin to the Mexico border. You think this has
"more common interests"?

[https://upload.wikimedia.org/wikipedia/commons/2/24/TravisCo...](https://upload.wikimedia.org/wikipedia/commons/2/24/TravisCountyDistricts.png)

Regardless of desirability, gerrymandering does not by definition increase
homogeneity. It's a tool that is used for political gain, whatever that may
be.

------
teslaberry
gerry mandering is a symptom of democracy not the problem.

democracy is the problem, or rather it is a form of self governance which
presents many dillemas.

historically , we know the bigger and more mature a democracy gets , the more
it ages into socially defunct patterns of corruption , lowest common
denominator, the decay of ethics, and embedded social passivity.

the solution to 'gerrymandering' is the end of our current democratic system,
not some 2 bit claim that an algorithm is a solution to a symptom of a bigger
problem .

~~~
saryant
And replace it with what?

~~~
hackeraccount
Duh. Something better.*

*"better" is left as an exercise for the reader. I have a better solution but the margins of this textbox don't provide enough room for it.

