Recently, I was on a trip with my

family, and we listened to an NPR podcast called “Who’s Gerry, and Why is he so

Bad at Drawing Maps?” The issue that was

being discussed is a case (Gill v. Whitford) that the supreme court was about

to hear at the time. In 2010, many state

legislatures around the country were controlled by republicans. Also in 2010, there was a census. This means that all of these republican

controlled legislatures would be redrawing electoral maps for their

states. Naturally, the republicans drew

up maps that would benefit themselves.

This particular case is from the

state of Wisconsin. In 2012, democrats

got 53% of the votes, but only 39% of the seats. The republicans managed this by packing

democrats into districts where their votes would be, essentially, wasted, and

dividing up remaining democrats into areas dominated by republicans. This case was prominent because it was taking

place right before the lines being redrawn again in 2020.

One of the biggest problems with

drawing electoral districts is that it is not as simple as it seems. In a perfect world, each district on the map

would have the exact same population and a 50/50 split of republican and

democrat. Obviously, this cannot be

achieved by simply drawing some rectangles on a city. Real electoral maps, generally, look funny

because the districts are all kinds of abstract shapes and sizes.

A few years ago, the supreme court

heard a different case about gerrymandering of electoral maps. Basically, the justices decided to ask the

public what to do about it. Justice

Kennedy basically issued a public challenge to see if anyone could come up with

a solid solution to this problem. As it

turns out, the answer can be found through math. Two political scientists developed an idea

called the “efficiency gap formula.”

This formula is a simple math formula that allows anyone with access to

the proper statistics to be able to take out a calculator and quickly see how

fair the electoral map is. The

efficiency gap formula does this by measuring the amount of “wasted votes.”

Here’s how it works: First, the number of wasted votes is

counted. Any vote that does not

contribute to the victory in the election is considered a wasted vote. Votes that go over the simple majority needed

are also considered wasted votes (if there are 100 voters, any vote over number

51, for the winning candidate, is a wasted vote). Any vote that is for the loser of the

election is also “wasted.” The

efficiency gap is the difference between the number of wasted votes on each

side divided by the total number of votes.

In the end, you get out a percentage that shows which party is

benefiting most from the current legislative districts. In short:

After the numbers are plugged in, the

efficiency gap will be a percentage.

Researchers say that a gap greater than is too extreme

of a gap. A gap between 0% and 7% is a

fair map. A gap greater than 7% is

gerrymandered.

Below is an example of the

efficiency gap at work. There is an area

with 20 A voters and 30 B voters. The

area is divided into five electoral districts with ten people in each one.

There are two groups

with nine B’s and only one A. The other

three groups have six A’s and four B’s.

In the next visual, the areas with majority A are highlighted with pink,

and the areas with majority B are highlighted with yellow.

As shown by the drawing,

we can see that even though the B’s are majority in the population, it will be

extremely difficult for them to win the majority of the seats in the

legislature. The A’s will most likely

win seats in the pink districts, and the B’s will most likely win in the yellow

districts. Just from this example, we

can see that this map is gerrymandered to favor the A voters, but we can prove

it with the efficiency gap. The “wasted votes” are marked out with x’s in the

next visual.

Party A wasted

votes: 2

Party B wasted

votes: 18

() 100 = 32%

The efficiency gap is

32%, which means the map in this area is extremely unfair for party B.

Efficiency

gap can also be used to calculate the number of seats that should be won based

on the percent of the votes received.

First, you take the percent of the votes received, 57% for example. Then calculate what percent of the votes are

wasted. In this case it is 7%. Next, double this percentage (14%). Finally, add this percentage back onto the

original percentage of the votes. With

this formula, if a party gets 57% of the votes, then it should have 64% of the

seats in the legislature.

(Percentage of votes) + (percent of wasted votes )

This

concept was created based on actual elections.

This doubling of the margin is what actually tends to occur in real

life. This idea is called a “seat

bonus.” The party with the majority of

the votes gets a small percentage bonus in seats in the legislature.

The

efficiency gap is a concept created in response to a supreme court case that

deals with gerrymandering of electoral maps.

Basically, the efficiency gap formula gives the judges, as well as the

public, a way to mathematically prove that an electoral map is fair or unfair

for a political party. Now, anyone with

the proper information can easily plug in numbers and figure out a simple

percentage that tells whether or not an area is fair. Concepts from the efficiency gap formula can

also be used to determine what percent of seats a party should hold in

legislature based on the amount of votes that party received. With the next census coming up in 2020, the

emergence of the efficiency gap in 2017 could play a major role in elections

from 2021-2030. After the maps are

redrawn and one election passes, the government will have the ability to easily

check every map, and they will have a reason to make changes to unfair maps.

“Here’s how the Supreme Court could decide whether your

vote will count.” The Washington Post,

WP Company,

www.washingtonpost.com/graphics/2017/politics/courts-law/gerrymander/?utm_term=.0310e7645ec7.

“Who’s Gerry and Why Is He So Bad at Drawing Maps?” WNYC,

www.wnyc.org/story/whos-gerry-and-why-he-so-bad-drawing-maps/.