Part one:
Section 1:
The first exercise in this
assignment has us looking at the correlation between Distance (in Feet) and
Sound Level (in Decibels). My null hypothesis is that there is no linear
correlation between Distance and Sound Level. My alternative hypothesis is that
there is a linear correlation between Distance and Sound Level. The Pearson
Correlation test that I ran shows that there IS a correlation between the two
and it is a very high negative correlation (-.896). Therefore I reject the Null
hypothesis and fail to reject the alternative hypothesis.
| Table 1: Graph showing a very high negative correlation between Sound Level and Distance. Sound level is on the X-Axis while Distance is on the Y-Axis. |
Section 2:
For the second section of
Part One we created a Correlation Matrix of Milwaukee County in Wisconsin.
There are some patterns that we can gather from this matrix. One variable we
can look at is Percent White. When looking at Percent White we can see that
when it increases, other races decrease. This is rather obvious as when one
percent of race goes up then the other must go down, however in Milwaukee
County it is especially true between white and black. Milwaukee is one of the
most racially segregated cities in America and the high negative correlation
(-.887) shows that through statistical values.
Some more analytical
variables we can look at are the correlation between people who are below the
poverty line to people that walk to work. There is a low correlation between
the two which means that we can see that when proportions of people below the
poverty line increase, proportions of people that walk to work increase as
well.
Part Two:
Introduction:
I have
been hired by the Texas Election Commission (TEC) to run some statistics on
data from the 1980 and 2008 elections. They have given me the percent
democratic and voter turnout for each election. I wanted to add another variable
to maybe shed some light on why we might be seeing the patterns that we see
after running the statistics tests, so I have also downloaded a Hispanic
population dataset.
The reason why they want me to
analyze this data is to determine if there is a clustering of voting patterns
anywhere in state along with if there is a clustering of voting turnout
patterns. The TEC wants to give this information to the governor to see if over
a 30 year period the patterns have changed throughout the state. To run this
data analysis I will be mostly using GeoDa and SPSS to determine if any
patterns take place. The TEC specifically wants me to determine if there is any
special autocorrelation within the state.
Methods:
To
start the data analysis I first had to gain access to all of the required data.
Luckily for me the wonderful TEC commissioner has provided me with the Texas
election data. It is up to me to get the Hispanic data, so I choose to go
through the Census Bureau. I got the Percent Hispanic Population for 2010 and
while I was there, I also downloaded the county shapefile for Texas. Now I have
all the files that I need to run the statistics, all I need now is the software
to do all the complicated stuff that I cant do. No need to download any
software as it is already on the computers so I jump right into GeoDa. Within
GeoDa I imported the Texas County shapefile and created a new spatial weight
since I would be running a spatial autocorrelation test. While creating the
weight I selected ROOK as the contiguity weight.
Now
since I determined the weight I am able to make Moran’s I and LISA Cluster
Maps. To create the Moran’s I was very self-explanatory as I simply clicked on
the Moran’s I icon and selected the variable I wanted and it instantly made the
graph. I then did that for the rest of
the variables and then moved onto the LISA Cluster Maps. This was just as
simple as I selected its own icon and then cluster map and WALA, I had myself a
LISA Cluster Map.
Results:
After
running all the tests I was left with 5 Moran’s I’s and 5 LISA Cluster Maps. I
can instantly see from the Moran’s I that over time (from 1980-2008) that the
counties that vote democratic have become more clustered. This is not the case
with the voter turnout as it seems to have gotten less clustered over time.
When looking at the percent Hispanic population we can see that it is very
concentrated and by looking at the beautiful LISA Cluster Maps that Geoda
created we can see where that is. As you see by Figure 1 we can see that
there is high clustering of counties that all have high Hispanic population in
the south along the US-Mexico border. There is also a cluster in the northeast
of counties that all don’t have high populations of Hispanics. We can see from
the other Cluster Maps that the same area that is occupied by a high number of
Hispanics also has a high number of counties that all vote democratic both in
1980 and 2008. One other pattern we see in the state (especially in south
Texas) is that those areas with high numbers of Hispanics and a high number of
democratic voters also have a low percentage of voting turnout.
![]() |
| Figure 1: LISA Cluster Map showing percent Hispanic Population. |
![]() |
| Legend for LISA MAPS |
One
interesting thing that goes against the pattern that we see through most the
state is that the Dallas-Fort Worth area (Figure 2) has a high voter turnout
but with a higher Hispanic population as well. It doesn’t show up on the map in
Figure 1 because all the counties around it have a much lower Hispanic
population and due to the Rook Contiguity Weight that I put on before, those
high Hispanic counties are affected by the lower Hispanic counties to the top,
bottom, left, and right of them.
![]() |
| Figure 2: LISA Cluster Map showing voter turnout in 2008. |
Here are the other Moran’s I and LISA Cluster Maps:
![]() |
| Figure 3: Moran's I for Percent Hispanic Population |
![]() |
| Figure 4: Moran's I for Percent Democratic 1980 |
![]() |
| Figure 5: Moran's I for Percent Voter Turnout 2008 |
![]() |
| Figure 6: Moran's I for Percent Voter Turnout 1980 |
![]() |
| Figure 7: Moran's I for Percent Democratic 2008 |
![]() |
| Figure 8: LISA Cluster Map showing Percent Democratic 1980 |
![]() |
| Figure 9: LISA Cluster Map showing Percent Democratic 2008 |
![]() |
| Figure 10: LISA Cluster Map showing Percent Voter Turnout 1980 |
Conclusion:
As far
as if election patterns have changed over time I would say they have but only
slightly. There doesn’t seem to be any mass migration of voters but rather
individual little pockets of change that pop up over the state. Those pockets
of change seem to be around urban areas with regard to voter turnout and rural
areas with regard to democratic voters. I would think that this could be due to
the huge turnover of rural to urban populations that we have experienced over
the last 30 years with a majority of our population living in urban areas
now. I do not believe that any of these
patterns will affect elections in an astronomical way nor does anything need to
done to redistrict Texas in order to make up for these changes.
Sources:
Texas
Election Committee
U.S.
Census Bureau











No comments:
Post a Comment