Wednesday, February 25, 2015

Voter Migration and the American Electorate

When viewing a map of the political partisan spatial layout amongst states in the United States one can see it is nonrandom. The partisan clumps that exist within the United States are "self-perpetuating" and voter migration in homogenous partisan groups is increasing over time. The consequences of these homogenous partisan groups require more study. Bishop asserts that the clustering of like minded groups only narrows ones point of view. Whereas, in "heterogenous communities [they] teach their members to compromise" through exposure of opposing view points. Bishops assumes that if this trend continues within the states then it will result with a country of "intolerance that will tear...apart at its seams". This study is concerned with what is creating and defining these partisan boundaries and if geographic sorting in the electorate is an issue at all.
It is important to consider all of the factors that could be contributing to this unbalanced partisan spatial layout. Some of these factors include "population migration,...polarization of the national parties and the evolution of individual attitudes". This migration of ideals is a natural occurrence as one gravitates towards social settings compatible with their own mindset. In order to truly determine this individual migration this study focuses on individual patterns such as migrating towards or from like minded areas.
Data from the YouGov Cooperative Congressional Election Study supports the idea that partisanship is heavily considered during relocation. They acquired this data from a national sample taking from recent movers asking them to rank in importance their different considerations for their final choice in destination.
Even though co-partisanship was not the foremost considered reason for the final destination of the movers about 30 percent did heavily weight partisanship. This percentage can make a substantial effect. Despite being able to see concentrations of partisanship across the country it is hard to determine wether individual migration contribute to these apparent partisan differences. This study is the first of its kind in examining geographic sorting effects. However, this study concludes that jobs and family concerns remain to be the most important factors in regards to migration. 


This article was on a study done in the Whiteoak Bayou Watershed, which is located near Houston, TX. The study looked at the watershed's ability to urbanize without being compromised. Generally, a watershed can handle some development and runoff because they have a certain capacity for adjusting to change. The study used a GIS technique called Spatial Metrics to look at how the land was being used and to view changes to it, and to see if the development and runoff patterns had caused the watershed to be pushed beyond where the hydrologic conditions could correct themselves. The method allows the land to be divided into different categories so that it can be more thoroughly analyzed. Once all the development data was collected the people conducting the survey converted the information into raster data, assigning different values to developed and undeveloped areas. This raster data was then converted into spatial metrics that allowed the researchers to identify important information about runoff.
As you can see from the graph above, there is an obvious upward trend in the amount of runoff that occurs each year since the 1950s. The researchers concluded that this watershed reached a level beyond that which it could handle. The runoff depth was effected by both the amount of development in the area, and the amount of precipitation. The researchers also noted that this method was done specifically for this area, and any application of it to other watersheds should be done with care.

Olivera, Francisco, and Buren B. DeFee. "Urbanization and Its Effect On Runoff in the Whiteoak Bayou Watershed, Texas1." (2007): 170-182.

Monday, February 23, 2015

Accuracy of iPhone Locations: A Comparison of Assisted GPS, WiFi and Cellular Positioning

The 3G iPhone was the first consumer device to provide a seamless integration of three positioning technologies: Assisted GPS (A-GPS), WiFi positioning and cellular network positioning. This study presents an evaluation of the accuracy of locations obtained using these three positioning modes on the 3G iPhone.The GPS technology adopted in most cell phones employs a server-side component
for the processing of the GPS signal and is referred to as Assisted GPS (A-GPS). While
high-sensitivity GPS chipsets have been adopted in recent years, A-GPS does not work
well indoors and as a result complementary positioning systems are employed under
these conditions.

Description of the positioning method behind the WiFi positioning system
Statements by Skyhook Wireless regarding the performance of its WiFi positioningsystem

Most GPS-enabled cell phones, including the 3G iPhone, employ a technology known as Assisted GPS (A-GPS). With A-GPS many of the functions of a full GPS receiver are
performed by a remote GPS location server. This remote server provides the A-GPS
mobile device with satellite orbit and clock information; the initial position and time
estimate; satellite selection, range and range date; and position computation.

Topography-based Analysis of Hurricane Katrina Inundation of New Orleans

Geospatial data are critical for hurricane response and recovery activities,and topographic data are a primary requirement. High-resolution, high-accuracy elevation data were used extensively during the first weeks of response to Katrina to provide rough estimates of inundation, and they continue to be
useful for studies of the impacts of the storm. Lidar is a relatively new remote-sensing technology
that has advanced significantly over the last 10 years and is now a standard survey tool used by the mapping industry to collect very detailed, high-precision measurements of land-surface elevations. In an effort to improve the quality of the Nation’s topographic data available for mapping and scientific
This image uses colors to represent the sea levels of New Orleans. 
applications, the U.S. Geological Survey (USGS) has been integrating recently collected lidar elevation data into the National Elevation Dataset (NED).

Lidar data were collected for southeastern Louisiana in 2002 under the auspices of the Louisiana Oil Spill Coordinator’s Office. These data are publicly available through Atlas, the Louisiana statewide geographic information system Web site operated by Louisiana State University
This image has taken the image above and converted it into the lidar site. 

Coupling Geographic Information Analysis Techniques with Ethnographic Methods in Urban Research

This article that I have selected to write about emphasizes on how GIS has recently been adopted in the ethnographic component of the Welfare Project. We must understand that when the Welfare Project was being created, GIS was not thought as an original design. We can identify some of the
challenges and opportunities faced in promoting GIS within multi-site ethnography and describe some of the ways we have used GIS to facilitate distance-based ethnography. One advantage of the mapping and data visualization capabilities of a GIS is that the system can handle data collected on multiple spatial scales.
This image is just one example on how we can use GIS to map population densities 
The Welfare Project includes a focus on children and child development, includes a disability component, incorporates qualitative data from an extensive ongoing family and neighborhood ethnography, includes both welfare recipients and non-recipients, is based in three different geographical contexts, and is longitudinal in design. Within the Welfare Project, we characterize the ethnography as being one of ‘‘structured discovery,’’ an approach that focuses on primary research topics while building in sufficient flexibility to capture emergent themes and unanticipated information.

The coordinating site pursued multiple strategies to introduce GIS concepts and methods to ethnographers. Throughout the project we have worked with one or more sites to create new and integrate existing geospatial databases within a GIS framework. The intent was both to demonstrate to the sites what we could do with the data they collect and to encourage the collection of geographic
identifiers, however crude, on the location of family activities and neighborhood resources within each city.

A “Neogeographical Education”? The Geospatial Web, GIS and Digital Art in Adult Education

To understand neogeography, the basics of science of geography plays a key role. A linkage between science of geography and digital art are a relationship provided by neogeography. As explained by Fivos Papadimitriou, neogeography encompasses the traditional ideas of geography while also participating in newer ideas such as a variety of personal, intuitive, absurd or artistic explorations and representations of geographical space. With the help of neogeography there is a new outlook on what is going on beyond the traditional geography, the perspective now demonstrates a larger view on spacial experiences through a digital cartography. Although neorogeography has been an idea from middle 1990's it's techniques were not very popular. It was not until recently that neorogeography became a questionable notion in relation to its impact on geographical education. Along with considering neorogeography, Papadimitriou assesses the Geospatial Web and digital art and their impact in geographical education. From one outlook, neogeography allows for individuals to interpret the historical and cultural dimensions of the enrichment of geography. Meanwhile there are those who would argue that using neogeography and Geospatial Web will lead to the end of GIS workers to amateurs who can now photograph and upload their own pictures on the web. Now the goal is to continue to create more advanced technology to make GIS workers job easier and widespread.

Topography-based Analysis of Hurricane Katrina Inundation of New Orleans

After the effects of hurricanes along the coast of Gulf of Mexico and the United States, the importance of high-resolution, high-accuracy elevation data proved valuable for development of topographic equipment. Because of the equipment there were a couple of light detections of hurricane Katrina causing the inundation in New Orleans a few years back. In order for a community to take the proper cautions and procedures, geospatial is a critical factor. Since the day of the trauma caused by the hurricane, high-accuracy elevation data was one of the resources used to estimate the inundation. As technology increases the mapping industry is able to create a clear high-precision measure of land-surface elevations, placing a large pressure on incorporating newer techniques like the lidar elevation data. Thanks to the involvement of the new elevation data that was installed around June 2005, about two months prior to the hurricane, people were able to properly respond to Katrina. Due the availability of the elevation data collected in 2002 from southern Louisiana, it became a beneficial resource to many geospatial data users who were responding to the aftermath of Katrina to have the information online. Few after the effects from the hurricane there was a high demand for maps to illustrate an estimation of how much of the city would be flooded.

Gesch, D. (n.d.). Topography-based Analysis of Hurricane Katrina Inundation of New Orleans. Science and the Storms: The USGS Response to the Hurricanes of 2005, 53-56.
The chart is an illustration of the contribution of foot of flood water per cumulative flood volume and area within New Orleans, La during September 2005. The flood depth is measured in relation to the elevation of the water surface within the city. For example, at elevations of 10–12 ft (3–3.7 m) below the elevation of the floodwater surface, only a relatively small area of less than 5 mi2 (13 km2 ) is inundated, but at the elevation of the water surface as measured on September 2, nearly 75 mi2 (194 km2 ) are inundated."

Wednesday, February 18, 2015

Global Consequences of Land Use

               This article discusses the effects of land use on the environment. Looking at food resources, freshwater resources, forest, regional air quality, and infectious disease. Using GIS they are able to address a growing issue that has gone on unmonitored for hundreds of years.
                After evaluating the information it is discovered that agriculture and pasture land rivals that of the largest terrestrial land mass or ecosystem. with nearly 40 percent of all land being covered by either farms or pasture land. This has a profound effect on runoff into the water tables and irrigation drawing water from the water table both very unsustainable practices. Also the increase of infectious disease is allowed to spread much more rapidly and uniformly. Most all excess nitrogen and phosphorus that runs in to dead zones of river deltas resulting from the clearing and subsequent use of farming practices on the land. Since 1850 over 35% of human carbon emissions have been attributed to land use and change. Often from the amount of energy and heat either reflected or observed. Often any land change often leads to a radical change in the hydro logical cycle to account for irrigation and sanitation.

               The map blatantly displays the change of land over thousands of years of use and what it was used for or the Bio sphere in each area. Land change can be caused from a number of reason not addressed in the map but related to deforestation, road construction, dams, and urbanization all increase the rate of deforestation. Not shown but could be interesting would be the a map that shows the 40% or so of the eroding and currently degrading land.
                     This is a growing issue that needs to be addressed and better managed using GIS we are able for the first time address the whole picture and see the change over time, for what reason, and how to combat the change and resulting effects on the environment.

Foley, Johnathan A. "Global Consequences of Land Use." Science 309.11 (2005): 570-75. Print.

Statistical confirmation of indirect land use change in the Brazilian Amazon

           One environmental impact that has raised serious concerns is loss of Amazonian forest through indirect land use change (ILUC), whereby mechanized agriculture encroaches on existing pastures, displacing them to the frontier. This phenomenon has been hypothesized by many researchers and projected on the basis of simulation for the Amazonian forests of Brazil. It has not yet been measured statistically, owing to conceptual difficulties in linking distal land cover drivers to the point of impact.
           Global demands for food and biofuel are expected to soar in coming decades . To meet these demands, new land will need to be brought into production. Brazil, with its abundant land resource, will no doubt continue to play an important role as a global supplier of agricultural commodities . Although conversions of forest to mechanized agriculture have been observed, pasture expansion remains by far the primary direct cause of Amazonian deforestation. Recent research suggests, however, that mechanized agriculture may exert a significant indirect effect, by the displacement of old pastures, and their recovery on the forest frontier. The present letter takes this displacement mechanism as ILUC, for the purposes of its analysis.

           In general, statistical explanations of land cover change have defined explanatory and dependent variables for a single location, possible with a set of nearby neighborhoods, a method that does not capture the effect of potentially distant influences. The approach in this letter overcomes the problem of distal spatial effects by using GIS to associate locations in the forest frontier where deforestation is occurring with ‘distant’ neighbors in the settled agricultural parts of Amazonia. The statistical models implemented possess a sufficiently general form that they can be implemented wherever ILUC is of interest to policy makers.
            The statistical models indicate that deforestation in the forest frontiers of the basin is strongly related to soy expansion in its settled agricultural areas, to the south and east.

Source: Arima, E. Y., Richards, P., Walker, R., & Caldas, M. M. (2011). Statistical confirmation of indirect land use change in the Brazilian Amazon.Environmental Research Letters6(2), 024010.

Socioeconomic Status and Prevalence of Obesity and Diabetes in a Mexican American Community, Cameron County, Texas, 2004-2007

In recent years there has been an increase of diabetes cases, not only in the older population but varies from young adults and children to elders. One of the leading factors for this large increase of diabetes cases is the increase in poverty among minority groups. Finding a group within US boarders, a group of people were chosen to partake in an experiment to determine the increase of obesity and diabetes within the community. The selected population consisted of 310 people from ages ranging from 35 and 64 years old. More specific, the goal of the experiment was to look at the socioeconomic statuses within Mexican American communities to determine whether or not it played a role in their health. GIS was then incorporated to illustrate "the spatial distribution of households by income quartile and the density of sampling." Using longitude and latitude coordinates to geocode the location of the households were revised for accuracy and later layouts were created through ArcMap. Overall the conclusion was made that due to low socioeconomic income Mexican American families along the borders had higher populations of children with diabetes. Due to the lack of insurance and or lack of money, there is a large percentage of children who go undiagnosed along with the overall factor of being in risk of developing the disease somewhere along their futures. 

The graph is a representation on the part of the research focused on the percentage of participants who tested positive for diabetes. Considering Cameron County Hispanic Cohort from 2004 to 2007, the information is categorized through ages and by socioeconomic status. The first quartile consisted of participants with an income of < $17,830, and people in the third quartile whose incomes ranged from $24,067-$31,747. 

-Hoch, F., & P, S. (2010). Socioeconomic Status and Prevalence of Obesity and Diabetes in a Mexican American Community, Cameron County, Texas, 2004-2007. Preventing Chronic Disease: Public Health Research, Practice and Policy, 7(3), A53-A53.