Monday, January 26, 2015

Taking Pulse of Socioeconomic Disparity on the Border: A Look at Diabetes Distribution in Cameron County

This study focused on Cameron County to highlight the socioeconomic disparity within a racially homogenous area of the United States. Issues of race and ethnicity, and the intersection of these characteristics with socioeconomic status, are difficult to discuss, however the systemic segregation of populations and resources are clearly illustrated in this research. Lower socioeconomic status, noted in this study as individuals with “annual household income… $17,830 or less,” is correlated with higher rates of undiagnosed diabetes and health complications. 
This study used a sampling frame from the residents in Brownsville, a border city with a dominant Mexican American population with 8 international border crossing points, used 2000 US Census data to determine the socioeconomic status and clustering of residents. Using a stratified cluster sampling method, this study had 810 respondents from 47 census tracts, aged 35-64.  These respondents were divided into those with a lower socioeconomic status, lower SES focused in the first quartile in Figure 1,  and a higher socioeconomic status, or those with an annual household income from $24,067 to $31,747 in the third quartile of Figure 1, the median within Cameron County. This study used a geographic information system to create a visual representation of households based on income and density. The respondents’ households were geocoded using coordinates gathered by a GPS, and referenced street addresses on maps within ESRI ArcMap software. 

Less than 25% of respondents had private health insurance, 5% used Medicaid, and 5% used Medicaid or Medicare as well as another form of health care. More than 50% of the respondents in either SES were within the “obese” range. 10% of respondents in the lower SES were informed they had undiagnosed diabetes through this study. In respondents ages 55 to 64, shown in Figure 2, those with lower SES had significantly higher rates of diabetes. Lower SES were significantly associated with undiagnosed diabetes. However, those with lower socioeconomic statuses are far less likely to have a regular physician, or even the expendable income to treat medical problems. 

Problematically, this study did not address the distribution or availability of medical care within the city and census tracts. The availability of parks, medical clinics, schools, or sources of healthy foods have a great impact on the health of the population. Brownsville, like many border cities in the Southern United States, has a large number of factories that employ workers for laborious jobs without providing living wages or manageable conditions. While the respondents were long term residents of the United States, this study did not explain the impact of the“Mexican culture”, which “can also move freely across the border”, simply planning to study the acculturation process in following years, implying a cultural source and not systemic problem in the United States.

AR, S. J., Pérez, A., Brown, H. S., & Reininger, B. M. Socioeconomic Status and Prevalence of Obesity and Diabetes in a Mexican American Community, Cameron County, Texas, 2004-2007.

Farmers Market price comparison


With the goal of providing the public with an insight on what would be the longterm effects of consumers wallets, this research looks at a wide parameter. Over looking the challenges that come with location bias, researchers decided that taking old PCS (price- comparison studies) and finding ways to use them in order to provide price information that should be correct for those who it includes. Although past PCS had there own challenges it helped researchers come to yet another problem in farmers markets. In particular, where does local food come from? 

Wanting to understand what was happening to the ideas of local foods a group of students reviewed there own PCS near Austin in 2012 around March through April. Focusing specifically in three locations, Downtown Austin, Cedar Park, and Georgetown,  researchers was done through price comparisons, looking over surveys along with observing those around. The origin of food makes the price range sky rocket, and yet people continue to consume "local products" rather than buying them in their local grocery store. 

Source: Long, J., Sounny-Slitine, M., Castles, K., Curran, J., Glaser, H., Hoyer, E., ... Parafina, B. (2013). Toward an Informative and Applied Methodology for Price Comparison Studies of Farmers’ Markets and Competing Retailers at the Local Scale. Journal of Agriculture, Food Systems, and Community Development, 95-119. Retrieved January 27, 2015.

Neighbourhoods and health: a GIS approach to measuring community resource accessibility

Recently, GIS applications have been used to analyze phenomenon such as "Food Wastelands" which have a negative effect on disadvantaged populations in New Zealand. The problem is compounded when long travel times to facilities such as day cares, ERs, and Marae buildings mix with a poor public transportation infrastructure.

New Zealand has one of the highest rates of car ownership in the world, and for the 10% of households without a car this makes access to necessary services very difficult. Living in rural areas that can have upwards of two hour travel times (by car) to the nearest grocery store or day care center can spell disaster for a family that needs to commute. In order to see these trends, 38,350 population based units of New Zealand where analyzed to determine travel times to sixteen health related resources. These units are geometric shapes based on population size (about 1,000 individuals) ranging from small urban kilometer-squared areas to thousand-kilometer squared rural areas. Access to the resources was determined by measuring distance from the population center (not geometric center) of the units following roads (instead of straight lines) to the nearest resource. Trends were found where rural areas had a shorter travel time to beaches or parks while urban areas had better access to food and schools.

This map shows the travel time in minutes of each unit in New Zealand, with major cities having very short travel times while rural areas such as the South-West had long times creating effective "food wastelands".

Maps like these can be used to determine relationships between poverty in an area and lack of access to health resources. Improvements can be made in city planning for areas that have poor access to multiple resources, such as improving public transportation in suburbs such as the ones in the map of Wellington below.

In creating this index of New Zealand, the researches have developed a tool that is quite plastic when it comes to applications. Travel times can be adjusted for different modes of transportation such as walking or biking in urban areas, population densities in rural areas can determine infrastructure range, and new niche markets can open up for food and health resources in in-between areas that have moderate travel times to get anywhere.

Source: Pearce, J., Witten, K., & Bartie, P. (2006). Neighbourhoods and health: a GIS approach to measuring community resource accessibility. Journal of epidemiology and community health60(5), 389-395.


Validity and Usefulness of Laws in GIS

Even to the trained eye, it is sometimes difficult to spot the obvious.  This was the relationship that existed in the case of Tobler’s First Law (TFL) and the art of Geographic Information System (GIS).
According to ESRI, TFL states that, "Everything is related to everything else, but near things are more related than distant things."  Meanwhile GIS is the study of the surface of the Earth.  The science of GIS is that it sees the way the world looks, instead of how it works.
The facts specified by examining the information provided by a GIS program can be interpreted to establish any correlation or pattern in an environment.   GIS can also be seen as a tool to create new theories and test them in simulated models and computer algorithms.
The data of the environment, as represented in a GIS program, requires people to recognize and note the smallest of details on the satellite map.  As a result, GIS and TFL have a strong correlated relationship.  GIS is used to monitor all the variables associated within TFL.  In retrospect, the connection between Geographic Information Science (GIS) and Tobler’s First Law (TFL) may seem obvious, but so was the Law of Gravity when it was first presented as the author mentioned.

Goodchild, M. F. (2004). The validity and usefulness of laws in geographic information science and geography. Annals of the Association of American Geographers94(2), 300-303.

The Toponymic Geographies of Commemorated African-Americans

Eliot M. Tretter's "The Power of Naming" explores toponyms (place names), specifically those commemorating African American notables. Before launching into his methodology, he explored the history of certain toponyms having to do with African American people (namely racist toponyms). As for his methodology, he collected the names of thirty African American notables and surveyed the number of toponyms using their names (like schools, streets, etc.) in the United States. His findings yielded that most toponyms honoring African American notables could be found in the South, New York, and California (all places with large black populations). Toponyms could usually be found in the home states of whoever they honored, but they also occurred in other states in which these individuals had a strong presence. There were certainly many MLK Jr. commemorations in his findings (which was no surprise to me; the number was well over 1000); and the names of men were more prevalent than the names of women when it came to these toponyms. However, Sojourner Truth was the woman with most toponyms that commemorated her name. It was very interesting that he portrayed whiteness as a racial category, as it is generally not treated as such (as it is generally seen as the "norm"). His concern to meet the standards of current critical race studies made this article

Source: Eliot M. Tretter (2011): The Power of Naming: The Toponymic Geographies of Commemorated African-Americans, The Professional Geographer, 63:1, 34-54

Obesity and Diabetes in a Mexican American Community, Cameron County

Nowadays, Mexican Americans are at increased risk for obesity and diabetes. The author established a cohort on the United States Mexico border to determine the prevalence of obesity and diabetes in this Mexican American population and to see whether minor economic advantages had any effect on health.

By randomly selected and extensively documented 810 people aged 35 to 64 years,the data were analyzed to establish prevalence of obesity and diabetes and other markers of poor health such as elevated glycated hemoglobin levels.

Rates of obesity (body mass index ≥30 kg/m2) were 57% in the first (lower) of 4 socioeconomic strata by income and were 55.5% in the third (higher). People in the higher socioeconomic stratum were significantly less likely to have undiagnosed diabetes (2% vs 9%). Among people aged 55 to 64 years, rates of diabetes were significantly higher among those in the lower socioeconomic stratum than among those in the higher stratum. Rates of un­diagnosed diabetes had similar differences. Approximately three fourths of the respondents reported having no health insurance, and there is no difference between people in different socioeconomic strata.

Rates of obesity and diabetes in this border community are among the highest in the United States. Belonging to the lower socioeconomic stratum significantly increased the likelihood of having undiagnosed diabetes and, in patients too young to be eligible for Medicare, the overall risk of developing diabetes. Modest improvement in income has a beneficial effect on health in this racial/ethnic minority community.

On the other hand,the use of GIS is to visualize the spatial distribution of households by income quartile and the density of sampling. They geocoded households by using latitude and longitude coordinates collected by global positioning system, and crosschecked with the street addresses to ensure accuracy.

Source: Fisher-Hoch, S. P., Rentfro, A. R., Wilson, J. G., Salinas, J. J., Reininger, B. M., Restrepo, B. I., ... & Hanis, C. M. (2010). Peer Reviewed: Socioeconomic Status and Prevalence of Obesity and Diabetes in a Mexican American Community, Cameron County, Texas, 2004-2007. Preventing chronic disease,7(3).

Land Use and Micro-Urban Heat Islands

The over exploitation of land through development has resulted in deforestation. A consequence of this deforestation has been micro-urban heat islands. Micro-urban heat islands are known as urban locations which produce hot spots within a city due to lack of tree coverage and improper land use. These hot spots are defined as areas producing temperatures warmer than the temperatures associated with tree canopies. Cities around the world are more commonly warmer than surrounding rural areas because of city layouts, heat from buildings, and heat release and storage. This study analyzes the micro-urban heat islands in relation to tree cover using LANDSAT TM, TM band 6 for a thermal map, and GIs in order to converge the layers. This study was conducted in Dallas in an area known as White Rock Lake.
This figure illustrates the layers used to convey micro-urban heat island's relation to tree cover. This analyses shows that the hottest spots in White Rock Lake are areas in which the land is being used in an impervious nature such as parking lots. It is important to note that older neighborhoods were reported to be much cooler in temperature than newer neighborhoods. The coolest areas in White Rock Lake were found to be near areas with heavy tree cover. 

The LANDSAT TM was extremely useful in obtaining and interpreting the data in order to form an argument for policy change. The results of the interpreted data suggest that urban areas should increase the amount of tree coverage and green space within the urbanized limits. As well as, increasing the overall density of the covered areas. Also, it is important to consider new urban neighborhood designs since they are fairly warmer than older neighborhoods. Policies and regulations on development and urbanization would help to curb these temperatures and promote green spaces. 

Aniello, C., Morgan, K., Busbey, A., & Newland, L. (October 01, 1995). Mapping micro-urban heat islands using LANDSAT TM and a GIS. Computers & Geosciences, 21, 8, 965-969.

Improving Retail Performance with Location Analytics

     With the economy in constant flux, retailers must stay in tune with the ever-changing demands of consumers and keep up to date on the status of their competitors in order to have a healthy and successful business.  With the state that the current market is in, even one unsuccessful store is one too many for a chain to be successful.  Thus, when deciding whether or not to move into a new location, several factors must be considered, such as if your store is in the right market with the right products for that demographical area or if there is enough sales opportunity to be able to compete against competitors and to cater to changes in consumer demands.  ArcGIS (a software) is a great tool for retailers to analyze these factors as it can be used to combine relevant data in maps and charts, helping the retailer to make decisions that would otherwise would be more difficult to make.  For example, Nike used GIS software to visualize where to distribute their products based on demographics, sales history, and various other factors (such as locations of schools with competitive sports teams).  
Another example is from 2008, when a barbecue restaurant closed just off Interstate 10 in Redlands, California.  The Redlands Chamber of Commerce turned to Esri, a company that utilizes GIS, for help in filling the empty lot where the barbecue restaurant once stood.  Ric Holderbaum, real estate director for the Dussin Group, expressed an interest that the Dussin Group was looking at Redlands as a possible new location for a new Old Spaghetti Factory restaurant.  Esri used Business Analyst Online to illustrate geographic data relevant to the Dussin Group.  This geographic data combined detailed income, age profiles, retail goods, and service expenditures for the area within a five-minute drive time around the location of the vacant restaurant.  The resulting data showed that a large percentage of the population fit into the demographic profile of the customers that the Old Spaghetti Factory usually serves.  Also, the fact that the location was right next to the highway meant that the location was exposed to more than 250,000 motorists every day.  The Old Spaghetti Factory opened there in December of 2009, and it has been very successful.  GIS software is very useful for a variety of reasons, one of which is the variety of things it can be used for.  It can be used to combine gathered data into an easy to understand map/image, making decisions based upon the information it reveals that much easier. 

Improving Retail Performance with Location Analytics. (2012, October 1). Retrieved January 27, 2015, from

Invasive Saltcedar (Tamarisk spp.) Distribution Mapping Using Multiresolution Remote Sensing Imagery

Saltcedar is a type of invasive species that has taken hold in the South and Southwestern United States. It originally came to the United States from Europe and Asia in the early 19th Century. It was brought by early settlers on purpose and by accident.  This research analysis of saltcedar looks at these populations through distribution mapping using multiresolution remote sensing imagery. It was achieved this through two types of analyses. First was five pixel-based classification were used through Quickbird and AISA.  The second analyses were done using Landsat TM imagery. The purpose of this analysis is to determine the distribution and density of saltceder populations in the United States, because of its destructive potential on native ecosystems.  

The results of this analysis showed that one type of process worked better than the other. AISA hyperspectral imagery performed better than other systems at mapping saltcedar populations in the South and Southwest. AISA outperformed Quickbird by roughly 10 percent. That 10 percent is in terms of accuracy of placing saltcedar in the correct place. All of the analyses showed a large distribution of saltcedars in local ecosystems.  This was able to show the best systems for mapping invasive species in the environment.  

Wang, L., Silván-Cárdenas, J. L., Yang, J., & Frazier, A. E. (2013). Invasive Saltcedar (Tamarisk spp.) distribution mapping using multiresolution remote sensing imagery. The Professional Geographer, 65(1), 1-15.

System,Science,and Studies

Chapter 1 basically explains what GIS is and how we as human beings use its technology in our everyday life. It also describes the origin of the GIS technology which was created in the mid 1960's in Canada. It was named the Canadian Geographic Information system or CGIS.  It also explains in great detail the different branches of technology that utilize the systems resources the most. Some say that this is the new way of solving real world problems with technology. Chapter one also briefly informs the readers the anatomy of the GIS database, meaning that it informs us how important the internet is to the operators of GIS. A company called ArcGIS is the number one user of the GIS database. Did you know that the GIS database was priced at over 5.9 billion dollars!! The five main components of GIS are also listed in this chapter. They are:The Internet, The users hardware, The software that runs on the users computer, The anatomy of the database, and finally the people who design, maintain, and run the system. Chapter one not only explains the technology side of GIS, but it also tell us about the business side of the system. Meaning how does this company turn a profit and there annual ratings.

Pictured above is Roger Tomlinson. The inventor of the first Canadian Geographic Information System 
I learned that the internet allows users access to specific functions that are provided by remote sites. The GIS world is highly influenced by the publishing industry which includes magazines, books, and journals. The first courses in GIS were offered in universities in the early 1970's, often as an overgrowth of courses in cartography and remote sensing. Did you know that in 1992 the term geographic information science was coined by Michael Goodchild in a paper he published. The one question that frequently is asked about the GIsystem is the system reliable enough for it to be used in geography. Many geographers are very skeptical about the GIsystem and still question its consistency

White rock Micro Heat islands

This blog stands out as it depicts the effect the suns rays heat and cool the earth and many of the contributing or off-setting factors. The author used thermal radar imaging to see where and why some places radiated more heat or why the areas are able to stay cool. A degree change of 6 to 11 is quite significant and can be the difference from a desert and a forest. His finding showed that the coolest areas were highly wooded and older building that had a lot of cover that absorb and radiates the heat from the Sun. Roofs of building bare ground and concrete are the biggest reflectors of heat and trap them. Greenery can off set much of the heat but not enough, the forest to the north maintains the coolest temperatures while the apartments and urbanized to the west and south have substantially hotter temperatures.

Spatial analysis on neighborhood effects and voter turn-out in College Station, Texas

     Through a spatial analysis of voter turnout and the " neighborhood effect" within College Station, TX, draws a relationship between voting at a precinct level with voters and nonvoters in three locations and the outcomes within their communities. The purpose of this spatial analysis is to examine the outcome of what happens within a local community (whether it be negative or positive) based on how socio-politically participatory the residents are. When analyzing three past referendums that were voted on within College Station, one in 1995 regarding a $10 million issuance for infrastructure in order to "reconstruct" the community, another in 1997 that initiated a prevention of construction of a City Convention Center, and one more in 1999 that was initiated in order to reopen a city street that was closed due to "the high nuisance through traffic."

           In 1995, the referendum initiated by the city council of College Station was the least cared about since it was the least controversial. Since it is completely appropriate to spend tax dollars on improvements around the city, there was no controversy. The referendum would be an overall improvement for everyone within the community making  a clear impact upon the voter turnout. Since the neighborhood effects would be an improvement overall, the voter turnout for the referendum to pass was the obvious winner.

                The results of the referendum initiated by voters in 1997 provide a more controversial argument due to a skeptical community regarding tax dollars going to a city convention center. Although the creation of the city convention center would stimulate economic growth and create new jobs, many residents argued against the city council. Many people opposed the convention center however; an equal amount of people favored as well. The referendum was passed as well but with a slimmer margin due to people being split upon the decision.

                The most controversial referendum in College Station was initiated in 1999 to force the city to reopen Munson Avenue. In order to greatly increase traffic on a street in one of the city's most attractive neighborhoods, many people argued back and forth opposing and in favor for the opening of the street Residents of Munson even being attacked by being called elitists by voters. Strong advertisement and media coverage opened this referendum to be a significance among all people within the community. The referendum, however, was passed "by a near 2-1 ratio" due to the strong media interest showing that Munson Avenue was perpendicular to the TAMU campus's south side. People in the voting precincts south of TAMU saw closing of Munson Avenue as a restriction of their traveling routes to TAMU. The voter turnout of this referendum was scattered and cluster which makes the effects of the neighborhood scattered and clustered as well.

                In conclusion, neighborhood effects in local politics are heavily influences by distribution of actual voters. The outcome among the community will be based on how many people oppose or favor what they want due each individual's self-interest.

Sunday, January 25, 2015

Geodesy and Geodetic Methods

What is Geodesy? 
Due to technology, the knowledge of Earth's shape and landscapes has changed over the years. Thanks to geodesy, studying these changes has become easier and more precise. Geodesy focuses on Earth's size, orientation, shape, and gravitational field as well as fluctuations in these values.

Modern Geodesy
Advances in modern technologies, such as GPS and synthetic aperture radar satellites, have allowed geodetic research to become even more precise. Modern geodesy gathers information using four basic techniques: positioning of geodetic instruments, altimetry, interferometric synthetic aperture radar (InSAR), and gravity studies. Efficient positioning of radio telescopes, satellite lasers, and GPS is necessary for precise geodetic measurements. Altimetry measurements gather data through changes in elevation instead of measuring 3D changes by alternative positioning techniques. Altimetry satellites shoot pulses at Earth's surface in order to gain ground measurements. InSAR uses SAR observations to produce digital elevation models. Gravity studies use satellite orbits to measure gravitational changes because satellite orbits are very sensitive to gravitational changes which makes them useful when determining the shape of the Earth. 

Applications (Global/Local) and Societal Implications

Geodesy can be used on a global scale to calculate global issues such as water budgets for each country. 
Using satellites to measure sea levels helps determine these figures. 

The same research methods can be applied on a local scale.Pictured above shows the use of geodetic 
tools to gather information about river and lake water levels in the Congo. This helps give insight 
into available ground water. 

As a result of these technological advances and their implementations, people can be better informed about the societal impacts of small changes in Earth's environment. For example, the severity of hazards that pose threats to coastal regions, such as flooding due to rising sea levels, can be measured more accurately using geodetic methods. The precision of geodetic measurements and the variety of applications for geodetic data make geodesy make it essential for understanding further many of the Earth's processes and humanity's impact on those processes. 

Wdowinski, S., & Eriksson, S. (n.d.). Geodesy in the 21st Century. Eos, Transactions American Geophysical Union, 153-153.

Local Food Systems

Globalization and industrialization of the food industry has forever changed the way of life for most people and led to a lack of ability for people living in urban centers to eat locally and organically. Eating locally is seen as the solution to the globalized food system and the issues that it has brought to our society. The common theme of urban centers is a lack of green space and ways for people to get fresh foods. And this lack of fresh foods is commonly centralized around the parts of cities with the lowest annual incomes. However, in Philadelphia, progress has been made and about 50% of the new community gardens are located in the <$18,000/year income districts (Fig. 2).

In mapping the local food system in Philadelphia, the amount of "food miles" that food travels from its source of production to the consumer was looked at and most of the food was determined to be local. Yet, the administrative boundaries of what is considered to be local may be skewed seeing as the average distance traveled is still 61 miles. With this in mind, it can still be said that progress is being made with community gardens filling some of the food availability gaps in low income neighborhoods. Using mapping technologies to determine distances of populations from food producers as well as finding available land that could be utilized for further development of the local food system, the future integration of local food production into the existing food industry is looking more promising than ever.

Kremer, P., & DeLiberty, T. L. (2011). Local food practices and growing potential: Mapping the case of Philadelphia. Applied Geography31(4), 1252-1261.

VGI as Big Data

Volunteered Geographic Information (VGI) is a term that can also be called "big data." Applications such as Foursquare utilize and are involved in the creation of big data. However, this is just one of the many tools that companies and businesses use to track certain data about their customers. The companies use the data/geodemographics to analyze customers, target groups, and ideal sale regions for the company's benefits.
This is a graph depicting movement using the Twitter application.

This type of data is coined "volunteered" simply because the users of the applications are considered volunteers by partaking in the use of the application. This information is collected through geographical datasets that are generated by the users and are put to use by companies and businesses. VGI can be considered a commodity in this aspect, because data is analyzed and applied for economic decision-making processes. One main problem with VGI is that the datasets don't allow for any definitive and respected interpretation of what is represented. There is a lack of knowledge and understanding about motives and contexts of the users, so a well informed analysis of the data is hardly possible. Perhaps the other main problem is the argument of whether the information is truly "volunteered" or not. Users go online and utilize the uses of the applications that are popular today, such as Twitter, Foursquare, and Flickr. It is argued that they are not using those applications in order to provide information to a third party for the process of geodemographic profiling. In contrast, it is argued that they simply wish to participate in the everyday uses of the applications.
This image shows tourist density that is calculated from the Flickr database.

Fischer, F. (2012). VGI as Big Data: A new but delicate geographic data-source. GeoInformatics15(3), 46-47.