Summer 2015 License Plate Game
By Mark Kloha
© 2015
The Hypothesis
The probability, frequency, and difficulty of finding a
license plate from any given state is related to three variables – population,
distance, and per capita income for that state.
The number of license plates that I find from any given state will be
highly correlated to a combination of these three variables.
Background
I've been playing the license plate game since I was a kid.
We would go on fairly long summer trips to various places across the U.S.
as my dad was a teacher and had the summers off. I spent a lot of time in
the car and needed something to do. When I was a kid, there were no iPhones
or apps. I had a notebook and a pen. I would make my lists of the
states and check them off as I found them. I would do this every summer
on our trips.
When I was a kid, I had made the connection fairly quickly
between frequency of a license plate and the distance and population of that
state. I remember I always had a hard time finding Idaho. It was
far away and not a lot of people. I didn't have any problems finding California. Even though it was far away, it was and is
the most populous state.
Recently, I was playing this game with my wife and kids, I
commented that there were a few southern states that were fairly difficult to
find. The states that I could not find were southern states that were not
that far away from Michigan and are not considered low population states.
Trish suggested that it was the economy of that particular state. I
considered it for a while and it made sense.
Now that I am older with kids of my own, an iphone with some
cool apps replacing the pen and paper, this summer we are on the hunt to find
license plates from all 50 states and to track how often we see license plates
from other states.
Methodology
Timing –
I will begin Wednesday, May 20, and go through Tuesday,
September 8 (Memorial Day Weekend through Labor Day Weekend). For the purposes of this research, each
‘week’ begins on Wednesday and ends on the following Tuesday. This timing allows the weekends to be grouped
together including the Mondays of holiday weekends such as Memorial Day weekend
and Labor Day weekend.
Tools –
When tracking license plates, I will be using an iphone app
to track when and where I see a license plate.
The app I am using is “License Plate Zone”. This app allows me to log any state and any
license plate multiple times. Most
license plate apps will only let me log a state once.
Trish does most of the driving on the weekends and in the
evenings. I will be able to log the
license plates quite effectively. If I
am driving and see an out-of-state license plate, I can press a button on my
iphone to talk to Siri through a Bluetooth-hands-free connection and have Siri
make a note of what license plate I just saw.
Then I can enter the information into the app later on.
How I’m Counting
I am only counting the official 50 States in the United
States of America minus the State of Michigan.
I am not tracking U.S. districts and territories. I am not tracking Canadian provinces or
territories.
Some states only require a license plate on the back of the
car. Some states require a license plate
on front and back. It is possible for a
car to have two different plates from two different states. This can happen if a person lived in say
Hawaii for a while, brought their license plate back (or even their car) to a
state that only requires a license plate on the back, and then they kept the
license plate on the front. For the
purposes of this study, front license plates do not count. That’s right – front license plates do not
count. Last summer I did see a Hawaii
license plate on the back of a pickup truck right here in mid-Michigan. I have seen a number of Hawaii license plates
on the front – while these are rare in of themselves, these front license plates
will not be counted. I cannot make an
exception for Hawaii because then I would need to make an exception for all
front license plates. Technically, what
counting the front license plate would do is increase the population of that
state to anyone who had ever lived there and just happened to keep their
license plate, and I have no way of adjusting the population factor to
accommodate these front license plates.
License plates from semi-trucks, U-Hauls, etc. do not
count. Depending on the state laws, it
is more beneficial for certain types of truck companies to be registered in
various states. I’ve seen a lot of
semi-trucks with Maine license plates but very few passenger vehicles with a
Maine license plate.
I will do my best not to double count license plates. For example, on my way into work, I see a car
parked on the side of the road and it has a Tennessee license plate. I see this car on my way into work every
day. If I’m at a campground, it is
possible that there are campers from out of state there. As we move around the campsite, I will not
record a license plate every time I see the same vehicle again later on.
Where I’m Counting –
I am only counting out of state license plates while in
Michigan. Our summer travel plans are
mostly in Michigan. We have several
weekend camping trips planned throughout Michigan. Also, I will be looking for license plates
just in our daily routines. We will be
going to Columbus, Ohio and Indianapolis, Indiana in June and August
respectively. While out of Michigan, the
license plates that I do find in these other states will not be counted.
Variables -
I have three variables – population, distance, and adjusted per
capita income,
Population
The population data is from the U.S. Census Bureau and its Estimated
2014 Population.
Per Capita Income and
Cost of Living
The Per Capita Income is from Wikipedia which in turn uses
American Community Survey 5 Year Average as its source.
While I was putting together this information in an Excel
spreadsheet, it occurred to me that the states have different costs of living
and that I should take that into consideration.
So, after a Google search I found a “Cost of Living” index for each
state. I then applied this index to each
state’s per capita income. I will be
testing for both the per capita income and the adjusted per capita income.
Distance
The fourth variable is distance. The app I am using lists the latitude and
longitude of where I found that license plate.
Then I had to figure out how to calculate the distance from that
particular point back to their home state.
I needed to define a single point in the other state to calculate the
distance back to that particular state.
I considered the following options for points in the other states:
1.
The state’s capital
2.
The state’s largest city
3.
The state’s largest metro area
4.
The state’s border
5.
The state’s geographic center
6.
The state’s population center
7.
Some average of the above methods
In some states, the capital, largest city, and largest metro
are all the same; in some states, all three are different; in other states, two
out of the three are the same; in some states, the largest metro area is
sprawling into another state.
For the final statistical analysis, I am using the distance
to the largest city as my distance variable.
Da U.P.
Michigan has an Upper Peninsula! I know.
I went to college there. I did
not use the U.P. border for any measurements to any other state. Approximately 80% of Michigan’s population
lives within a two hour drive of Michigan’s southern border, and 90% live
within a 2.5 hour drive of Michigan’s southern border. For people visiting Michigan, the large
majority of these visitors will come through the southern border rather than
through the U.P. border.
Shortcuts through
Canada and the Lake Michigan ferry boats
For the purposes of computing distance from Michigan to
other states, there were no shortcuts through Ontario, Canada to get to the
Northeastern states. To get from
Michigan to the New England states, it is quicker to travel through Ontario, Canada;
however, all distances are based on traveling through the United States. The one exception to this rule is
Alaska. It is possible to drive to
Alaska, and then it is necessary to drive through Canada.
To get to Michigan from Wisconsin, Minnesota, or other
western states, there are two car ferries that go across Lake Michigan. The Lake
Express goes from Milwaukee to Muskegon in 2.5 hours. When calculating routes in Google Maps,
Google Maps always said the quickest way to some places was via ferry
specifically the Lake Express. The S.S Badger goes from Manitowoc, WI to
Ludington, MI in 4 hours. The routes to
Wisconsin were based on driving through Chicago and not the ferry boats.
Distance to Hawaii
Calculation
It is possible to find a car with a Hawaii license plate on
the back in the mainland and even right here in Michigan. I’ve seen one. It is impossible to drive to Hawaii. I completely realize I am stating the
obvious; however, this obvious fact causes some concern as to whether or not
Hawaii should be included in the study.
Alaska has a population, per capita income, and a drivable distance even
though it is through Canada. Hawaii has
a population and per capita income but no drivable distance to Michigan. If I were to include Hawaii in this study,
then how should the distance be calculated?
If I use the actual distance from Hawaii to Michigan of 4,500 miles,
then this assumes that the distance is drivable. If it were drivable, then Alaska should be
more difficult to find than Hawaii.
It is possible to transport a car from Hawaii to California
by boat. It costs approximately a thousand
dollars (give or take a few hundred dollars) and takes ten days. http://www.matson.com/pov/booking/shipping_rates.htm
There are a few possibilities for dealing with Hawaii:
1.
Not include
Hawaii in the study
2.
Convert all the distances to a “time”
variable.
3.
Convert the shipping time and costs from Hawaii
to California to a “distance”.
I would like to keep Hawaii in the study. I do not want to convert all the distances to
a driving/traveling time. Driving time
is quite subjective with so many factors such as how many people are traveling,
are they traveling 24/7, are they driving slow, fast, speed of traffic, etc. I did not want to try to account for people’s
personal driving habits.
I came up with a method to convert the time at sea to a
driving time. It takes 10 days to ship
the car. The trip will take 10 days, and
assuming that an average driver could easily drive 500 miles in one day, then that
means the entire trip has been assigned a mileage of 5,000 miles from Hawaii to
California, and this will get the vehicle from Honolulu, Hawaii to Los Angeles,
California. The distance from Detroit,
MI, to Los Angeles, CA, is 2,270 miles.
So, adding the converted time on the boat to miles with the actual mile
from Michigan to California, this gives 7,270 miles.
As mentioned earlier, a license plate on the front of a car
does not count. I have seen many Hawaii
license plates on the front of cars; however, the back license plate was the
state the driver currently lives in.
Counting the license plates on the front actually increases the
population factor of the state. Not only
would you be looking for current residents of that state, you would be looking
for past residents who kept a memento of their stay their tattooed to the front
of their car.
Quick Summary –
1.
I am only tracking the official 50 States – not
including D.C or other U.S. territories.
2.
I am not tracking Michigan.
3.
Distances are measured from Michigan’s southern
border only.
4.
Distances do not use the short cut route through
Canada to get to the New England States.
5.
The distance to Alaska is based on driving
through Canada.
6.
Only license plates on the back of a vehicle
count
7.
License plates on semi-trucks and rentable
trailers/trucks do not count.
8.
I will be tracking both the frequency, date,
time, and location for where and when I see an out of state license plate
Results
During the 16 weeks, I traveled, 9,870 miles within
Michigan. I logged 1,400 out of state
license plates. The top 5 were:
Illinois
Ohio
Indiana
Florida
New York
These 5 states made up over 50% of my sightings.
The bottom 5 were:
Idaho
Delaware
Maine
North Dakota
Hawaii
Except for the bottom 5 states, I saw every state at
least three times. I saw Idaho and
Delaware twice; Maine only once; and no North Dakota or Hawaii. I was a little surprised that I did not see
any North Dakota plates.
The days of the week that I saw the most out of state
license plates in order:
Sunday
Friday
Saturday
Monday (Labor Day and Memorial Day both saw spikes
compared to the other Mondays)
Thursday
Tuesday
Wednesday
For the following statistical computations, the independent
variable is Frequency - how many times I saw each state. The three dependent variables as mentioned earlier
are population, distance, and per capita income adjusted. I did do some correlations with just the per
capita income but this was not used in the multiple regressions.
Correlations
Using Microsoft Excel, I ran independent correlations
between the following four variables and got the following results –
Population: 40%
correlation
Distance: -27%
correlation
Per Capita Income (PCI):
0% correlation
Per Capita Income Adjusted (PCIA): 23% correlation
So, population is the most significant variable. The distance factor is a negative
correlation. This means it is an inverse
correlation – the closer the state then the higher the frequency. I found it interesting that I got a 0% correlation
on the PCI but then it jumped to 23% once I adjusted the state incomes based on
the Cost of Living Adjustment factor.
When I take out the top 5 states and the bottom 5 states, I
get the following results –
Population: 59%
correlation
Distance: -29%
correlation
PCI: 16%
correlation
PCIA: 37%
correlation
In this analysis, the PCIA has a higher absolute value correlation
than the Distance variable.
Multiple Regressions
Using Microsoft Excel, I ran several multiple regressions.
For Population and Distance for 49 states
Multiple R: .471
R Squared: .222
Adjusted R Squared: .188
Pop t-stat: 2.961
Distance t-stat: -1.946
For Population and Distance without Hawaii – 48 states
Multiple R: .537
R Squared: .288
Adjusted R Squared:
.256
Population t-stat:
3.268
Distance t-stat:
-2.910
For Population and Distance without the top 5 and bottom
5 (39 states)
Multiple R: .698
R Sqaured: .488
Adjusted R Squared:
.459
Population t-stat:
5.328
Distance t-stat:
-3.164
For Population, Distance, and PCIA with 49 states:
Multiple R: .483
R Square: .234
Adjusted R: .18
Population t-stat:
2.966
Distance t-stat:
-1.182
PCIA t-stat: .825
For Population, Distance, PCIA without Hawaii (48
states)
Multiple R: .550
R Squared: .303
Adjusted R Squared:
.255
Population t-stat:
3.287
Distance t-stat:
-2.433
PCIA t-stat: .960
For Population, Distance, PCIA without the top 5 and
bottom 5 states (39 states)
Multiple R: .753
R Square: .567
Adjusted R: .530
Population t-stat:
5.667
Distance t-stat:
-2.458
PCIA t-stat: 2.526
My new variable
If I create a new variable - (Pop*PCIA)/Distance and run
a correlation of that with Frequency for the 49 state, I get a 91.7%
correlation!!
In the world of academic Geography, they like to be all
scientific and stuff and they have various equations to calculate interactions
between two places. It’s based on
Newton’s law of gravitational attraction F=m1*m2/d2. Gravitational Force is equal to the mass of
object 1 times mass of object 2 divided by the distance squared. This equation has been adopted by geographers
to the following:
Demographic Gravitation is DG = p1*p2/d2.
Demographic gravitation is equal to the population of
place 1 times the population of place 2 divided by the distance squared. The other equation is Demographic Energy –
DE=p1*p2/d. Demographic Energy is equal
to the population of place 1 times the population of place 2 divided by the
distance.
For the purposes of this research, I have adapted these
equations further. I created three new
variables:
P/D
= Population/Distance
PDIA
= (Population*Adjusted Income)/Distance
PIA=
Population*Adusted Income
Since I was focusing just on the license plates found
here in Michigan, it was not necessary to multiply the population of the other
states by Michigan’s population 49 times.
I ran the correlation between my new variables and
frequency for all 49 states and got the following:
P/D
= 89.2% correlation (without top 5 and bottom 5, this is a 90.2% correlation)
PDIA
= 91.7% correlation (stays the same without top 5 and bottom 5)
PIA
= 45% correlation (without top 5 and bottom, this is a 43% correlation)
Summary
It is readily apparent that the most significant factor
in sighting out of state license plates is the Population for any given
state. After that, the next most
important factor is Distance. The Per
Capita Income Adjusted variable is the weakest variable but should not be
entirely ignored.
So, if you want to calculate the difficulty of finding
any given state, or predict which states you will see more often than others,
simply take the population of all 50 states and divide that by the calculated
distance to the other state, and then rank them – the higher the number, the
easier that state is to find. FYI –
using the largest city or capital or border statistically will not make any
significant difference. Adding in the
adjusted income factor will only give it a slight boost and is more work to
find all the per capita incomes for all the states and adjust those based on a
COLA.
Sources –
|
http://www.missourieconomy.org/indicators/cost_of_living/
|
|
http://en.wikipedia.org/wiki/List_of_U.S._states_by_income#States_ranked_by_per_capita_income
|
Bonus Section –
Review of License Plate Apps for iphone
US PL8S
·
List of all 50 states and D.C. with only 1 plate
per state
·
List has feature to hide the states that have
been found
·
Has Statistics function – Lists what percentage
of the 51 States/District you have found (50 States plus D.C.)
·
For the individual states, it lists the date
found, how many license plates are issued for the state, and ranks the states
into four categories – easy, medium, hard, and very hard
What I like about this app is that it is very
simple. It’s great if you just want to
check off each state as you find it. The
information about when and where is also available.
License Plate Zone
·
For all 50 states and D.C., this app lists all
the plates issued in that state. It has
a picture of each license plate in that state.
This allows you to check off specifically which plate you found.
·
In the list of the States, it shows how many
different plates are issued for that state.
For example, Alabama has 161 different plates, Alaska has 35 different
types of plates, etc.
·
Map feature shows where it was found
·
Lists the date, time, and latitude and longitude
of when and where the plate was found.
·
The “Trips” feature lists how many plates from
how many different states have been found.
For example, my app currently says I have found 71 plates from 49
different states.
·
Lists all the plates in the order found along
with date, time, lat. and long.
·
Allows the same plate from the same state to be
selected multiple times if and when that particular plate is found again
·
Can edit the location. This means that if you are driving, you see a
license plate from Alaska, you wait until you are safely parked and enter the
information, it will drop a pin of your current location; however, you can move
this pin to where you actually saw the license plate.
What I like about this app is
that it has all the plates from all the states.
I also like the feature where you can edit where you found the license
plate. I like the fact that it lists the
order in which you found them. It allows
a person to enter the same license plate multiple times. This is the only app that allows a person to
do this.
Miles to Go
·
This app like the other apps allows you to track
which states you have found.
·
It has Facts and Quizzes section – this includes
capital, largest city, flag, statehood date and order of admission to the
Union, nickname, state seal, area and rank, population and rank, state bird and
state flower.
·
The quizzes can be customized to focus on just
certain aspects of the information in the facts section. Such as only being quizzed on capitals and
largest city versus being quizzed on everything from capitals to state birds.
·
It has a travel log – it is a notes section
where you can enter what cities you visited and what you did.
·
This app includes Canada. Canada has its own section of facts and
quizzes.
·
It has a “Progress” chart for the United States
and a separate chart for Canada.
·
It’s glitchy.
I cannot reset the game or reset a license plate if I incorrectly enter
that after I found a plate and need to fix it.
To reset the entire app, you can delete the app and then reload. If you just enter an incorrect state, it is
impossible to fix.
What I like about this app –
It has Canada!! The facts and quizzes section looks fun for
kids who want to learn some geography and history. The Notes section is a great travel log. It is glitchy. If you want a new game, you can delete the
app and then reload it. If you need to
reset a license plate, you are kind of stuck.
States and Pl8S
My least favorite app although
it has a few redeeming qualities –
·
It has a running “mileage score”. The score is based on your location to the
center of the other states. So, if you
are in Ohio and you see a Florida license plates you score more “mileage
points” for that license plate than if you are in Georgia and you find a
Florida license plate.
·
It has a reminder to not Play and Drive
·
It has a fun facts section for each state.
Summary –
The USPL8S app is the simplest
to use and great for kids who just want to check off if they found the state or
not.
The License Plate Zone app is
the one I use the most. I love the fact
that it lists all the plates for each state.
Also, multiple plates from the same state can be logged. This is the only app that allows a person to
do this.
The Miles to Go app is awesome
in that it has Canada along with the fun facts and quizzes section.
Then the States and Pl8S has the
awesome “Mileage Points” game.
My ideal app would combine the
License Plate Zone features with the Miles to Go features and include Canada
and list all the different plates from our northern neighbor. Then it would also tell you how far you were
from that state when you found it. Fun
facts, trivia, and quizzes is an awesome bonus.
