Week 8: Census Data 2000

    The Asian population is more dense in the West Coast as well as the North Coast. This is probably due to the massive Asian immigration to the United States a few generations ago. The result of the immigration is that immigrants seeking higher living standards tend to linger around in the more urbanized areas such as Los Angeles and New York City. In contrast, in the northern area of the US, the counties are covered in green - meaning that less than 1% of the population are Asian. The reason of this may be the result of traveling routes of the immigrants: they usually arrive in the US through the coastal areas and tend to stay there. The county with the highest concentration of the Asian population is one among the west coast - almost half of the population identify themselves as Asian. 

   The Black population is mostly concentrated in the southeastern tip of the United States. Due to the unfamiliarity of the US history, I cannot be certain of the reason of this concentration. One interpretation of this may be that this is the result of the slavery history until the 19th century. Similar to the Asian population, we can see that the black population tended to linger in the coastal area where they lived during the past and had not moved to other areas so much. This may be because of the cultural difference of the different races in different areas. In the north, there is again less concentration of the black population - generally less than 3%. The area with the highest concentration has a black population percentage as high as 86.4%.

    Some of the other races has the highest concentration in the southwestern tip of the United States. Again, one interpretation of this may be that the immigrants with hispanic roots tend to enter the States from the southwestern direction, since Mexico is in that direction. Interestingly, the county with the highest concentration of these races is significantly lower than that of the black population: 30% compared to 86.4% mentioned above. The cause of this is not clear: whether it is because people in this category are more scattered than Asians and Blacks or it is because the overall "other race" population is less in the United States could not be defined. In addition, the definition of "other race" in the census data could make a difference and should be taken into account when interpreting this data. 

The ArcGIS experience

    With the introduction of ArcGIS in this course, I have come to realized that geographers are of significant influence in both the private and public sector in our economy. As an economist, one thing that interests us is "incentive". People act on their incentives and incentives come from people's past experience or base knowledge of a certain material. Powerful maps and other GIS materials created by ArcGIS are good tools of leading people to understand certain materials in certain ways. Although maps are presentations of the reality, the process of map creation selects and arrange data in such way that lead viewers to certain conclusions the map makers intend to.  

     With that said, ArcGIS as a user-friendly data management and map creation tool is a very good assistance for not only geographers, but also businessmen, politicians and policy makers. An example of the use of map uses in marketing strategies is the case of Verizon advertising its coverage of 4G LTE network across the nation. With ArcGIS, more and more users could make full use of the beauty of maps in various industries. 

Week 7: DEM

      The area I have chosen is the Big Bear Lake Area. I have chosen this because this weekend will be the first time I go skiing and my first experience will be at the Big Bear Mountains. For this reason, I decided it would be a good idea to look at the local elevations of the mountains. The following is the information retrieved from the original source.
      Extent: Top: 34.4072222213; Left: -116.839166668; Right: -116.465000001; Bottom: 34.2069444435;
     Spatial Reference: GCS North American 1983
     Angular Unit: Degree (0.0174532925199433)
     Datum: D_North_American_1983
     It is relieving to see that the mountains are not as steep as I thought. There are no very steep slopes; Rather, one can gradually climb up or glide down the slope. I guess this would be good for a beginner.
    

3D map of the area

Week 6: Map Projections

    Map projections exist because of the unavoidable distortions when trying to put the three dimensional world onto a two-dimensional surface. Different kinds of map projections perserve different features of the Earth and therefore serve different purposes. In this lab, we learned to deal with conformal, equal-area and equal distant projections. When measuring the distance between two cities: Washington DC and Kabul, the significance and pitfalls of different projections can be seen.

     One of the most important uses of a map is navigation. If one wants to use a two dimensional map for navigation, the best choice is then probably a conformal map, since local  angles are preserved. However, from the two conformal maps I have chosen for this lab, it is easy to see that there is significant difference. Mercator is clearly more useful as a world map than stereographic since the stereographic projection usually just projects one hemisphere. The two representations of a sphere onto a piece of paper give the viewer different sense of the world. This, again, shows the "art of a geographer": representing the world in the way you want to to affect people's perception of the world.

     One pitfall of using different map projections is that when measuring distances, different projections give different answers. Although the two projections, equidistant conic and equidistant cylindrical projections both suggest that they perserve the distance characteristic of the world, the distance between Washington DC and Kabul is still significantly different. One may be confused by this without taking a GIS class. The equidistant projections preserves the proportional difference in distance: it does not mean the the distances one measures from two equidistant projections are the same. Without an understanding, a map viewer may be confused. 

    Another pitfall of map projections is also linked to the "art of a geographer". A map maker could "manipulate" people's thoughts by representing the world in different ways using different map projections. As the video we have seen in lecture suggests, some maps lead to the false perception that certain countries are smaller than others when they are actually the same size. As said in the video "Why are We Changing Maps"shown in lecture, the lady pointed out that the traditional Mercator projection has "fostered European imperialist attitudes for centuries and created ethnic bias against the third world". This has significant implications on social equality and is something that politicians and policy makers should be educated on.