It follows that geographical context is relevant to any discussion of the nature and implications of VGI and its enabling technologies. These devices are equipped with ready-made maps and Global Positioning System receivers, further empowered by a location-based service LBS.
LBS is an information service provided by a device that knows where it is and then uses that knowledge to select, transform, and modify the information that it returns to the user. Hence the device can supply driving or walking directions to businesses, restaurants, and automated teller machines; find other users in close proximity; or even send alerts, such as when a user is approaching a traffic jam or accident.
Peter Batty a former chief technology officer of two leading geographic information system [GIS] companies has recently introduced whereyougonnabe. There is growing concern that the proliferation of technologies and the production of detailed, micro-level spatial data are outpacing our ability to protect information about individuals.
The same techniques that allow Web users to create mashups by linking infor-. The social issues raised by these tools are more urgent today than two decades ago, and there is every indication that the urgency will grow in the future.
The geographical sciences are central to understanding the nature and implication of new forms of data acquisition. Geographical scientists have the background and training to bring to bear language, guiding principles, and theoretical constructs that are relevant to locational and mapping technologies.
They offer research methods that can facilitate the exploration, analysis, synthesis, and presentation of data about citizen mapping activities and their social implications.
The concern of geographical scientists with place and context is particularly important, as the study of citizen mapping and locational privacy is not just about acquiring and using locational data. It is about understanding how data are used and viewed in particular places, and by particular communities.
Bringing these concerns to bear on citizen mapping initiatives and locational data collection is essential to the effort to understand the social implications of geographical practices. The responsibility of the geographical sciences to confront this issue becomes clear when one considers that geographical research itself may infringe upon the personal privacy rights of individuals. Box The following research questions provide examples of issues that would be particularly productive to investigate.
Cityware researchers have installed scanners at secret locations around Bath. Those scanners capture bluetooth radio signals. Bluetooth is a short-range wireless technology.
The results are stored in a database. The researchers of this study maintain that the purpose of Cityware is not to track individuals, but to study the aggregate behavior of city dwellers as a whole, while also allowing those individuals to find their way around the city, participate in interactive citywide games and cultural activities, and access a host of information services while working, socializing, or relaxing Lewis, Producers of VGI are themselves subjects of much needed research e.
Initial studies have shown that people. Some are also motivated by self-promotion, the desire to fill in gaps in data, or merely to connect easily to friends, relatives, and colleagues Goodchild, Geographical methods for exploration, analysis, synthesis, and classification of spatial data e. A study that mapped participation and correlated it with multiple socioeconomic variables might, for example, reveal that most VGI in a certain region comes from upscale residential neighborhoods, and could further understanding of the social, political, and technological factors that affect how geographical data are developed, accessed, and interpreted Elwood, Research is needed to define the limits of VGI in this context and to shed light on the social psychology of the producers of VGI.
Institutional review boards IRBs have emerged in recent years to protect the rights of human subjects in research projects, and yet there is wide variability in their capacity to apply and disseminate confidential research Lane, This orientation could be a major impediment to useful research.
Turning to the evaluation of content and quality, VGI has been termed asserted information, to contrast it with the authority of traditional sources. While mapping agencies have developed elaborate mechanisms for quality control and assessment, the quality of VGI remains very much an open research issue although in other areas of volunteered information, such as Wikipedia, some preliminary research results are now available, e.
Researchers working on this topic need to develop ways for educated citizens to produce not only volunteered geographical information but also volunteered geographical analysis. Given existing perspectives and methods, the geographical sciences could develop rubrics to assess and evaluate the quality of VGI i. For example, Flanagin and Metzger discuss 1 emerging analyses and rubrics for geographical training and education of novices by experts; 2 assessment of the notoriety of systems such as the level of trust users now have in Wikipedia, Google Earth, Citizendium, etc.
Researchers could investigate the thematic limits of VGI i. Discussions of neogeography and of what can be achieved today by citizen mappers rarely include the issue of the digital divide—the sharp contrast between those with effective access to digital technology and those with limited or no access. Moreover the divide is growing, as certain groups acquire more and more technology and others continue with nothing. Since the proliferation of VGI could exacerbate the digital divide, it is important to understand better whether, and where, this might happen e.
The size, shape, and relative location of land masses would change. Projection is a major challenge for cartographers. Every map has some sort of distortion. The larger the area covered by a map, the greater the distortion. Features such as size, shape, distance, or scale can be measured accurately on Earth, but once projected on a flat surface only some, not all, of these qualities can be accurately represented. For example, a map can retain either the correct sizes of landmasses or the correct shapes of very small areas, but not both.
This determines which projection to use. For example, conformal maps show true shapes of small areas but distort size. Equal area maps distort shape and direction but show true relative sizes of all areas. There are three basic kinds of projections: planar, conical, and cylindrical. Each is useful in different situations. Imagine touching a globe with a piece of cardboard, mapping that point of contact, then projecting the rest of map onto the cardboard around that point.
They are often used for maps of one of the poles. Imagine you wrapped a cone around Earth, putting the point of the cone over one of the poles. That is a conical projection. The cone intersects the globe along one or two lines of latitude. When the cone is unwrapped and made into a flat map, latitude lines appear curved in circles or semicircles. Lines of longitude are straight and come together at one pole. In conical projection, areas in the mid-latitudes—regions that are neither close to the Equator nor close to the poles—are represented fairly accurately.
For this reason, conical projections are often used for maps of the United States, most of which lies in the mid-latitudes. The cylinder touches Earth along one line, most often the Equator. When the cylinder is cut open and flattened into a map, the regions near the Equator are the most accurate. Regions near the poles are the most distorted. Surveying and Remote Sensing Cartographers rely on survey data for accurate information about the planet.
Surveying is the science of determining the exact size, shape, and location of a piece of land. Surveyors gather information from regions both above sea level and beneath bodies of water. Surveying can be done on foot. Surveyors use many instruments to measure the features, or topography , of the land. A compass, measuring device, and theodolites are often used by surveyors doing field work. A theodolite is an instrument that measures angles. A surveyor may calculate the angle of hills, valleys, and other features by using a theodolite, which is usually mounted on a tripod , or three-legged platform.
Today, many surveyors use remote sensing to collect data about an area without actually physically touching it. Sensors that detect light or radiation emitted by objects are mounted to airplanes or space satellites, collecting information about places on Earth from above. One method of remote sensing is aerial photography, taking photographs of Earth from the air. Aerial photography has eliminated much of the legwork for surveyors and has allowed precise surveying of some places that are impossible to reach on foot.
Satellites, spacecraft that orbit Earth, perform remote sensing. For example, Landsat , a satellite that circles Earth 14 times a day, transmits huge volumes of data to computers on Earth. The data can be used to quickly make or correct maps. How Maps Are Made Before making a map, cartographers decide what area they want to display and what type of information they want to present.
They consider the needs of their audience and the purpose of the map. These decisions determine what kind of projection and scale they need, and what sorts of details will be included. The language of the map is one thing a cartographer must consider. A blind reader needs a map that has information in braille , for instance. The audience for a map can determine how widely a map is used. A map might use red and green symbols to show the location of maple and pine trees.
This information might be easily displayed in a simple legend. However, such a map could not be used by people who are color-blind. Lines of latitude and longitude are mathematically plotted on a flat surface. Features are drawn in their appropriate location. Before the development of advanced computer and printing techniques, maps were drawn by hand. Cartographers would draw, or scribe , the map on a sheet of coated plastic with a special etching tool, scraping away the colored coating to leave clear, sharp lines.
Several different sheets of plastic were layered on top of each other to add shading and place names. The plastic sheets were used to make a metal printing plate , or proof, for publishing the map.
Today, most mapping is done with the help of computers. The coordinates of every point are entered into a computer. By feeding new data into the computer or deleting old data, map changes can be made quickly and easily.
Colors can be changed, new roads added, and topographic features, such as the flow of a river, altered. The new map can then be printed out easily. Types of Maps Cartographers make many different types of maps, which can be divided into two broad categories: general reference maps and thematic maps. General reference maps show general geographic information about an area, including the locations of cities, boundaries, roads, mountains, rivers, and coastlines.
Government agencies such as the U. Many are topographic maps, meaning that they show changes in elevation. They show all the hills and valleys in an area. This is useful to everyone from hikers trying to choose a route to engineers trying to determine where to build highways and dams. They emphasize one theme, or topic. These themes can include information about people, other organisms, or the land. Many thematic maps are now made with the help of geographic information system GIS technology.
This technology combines information from maps with other data about people, the land, climate , farms, houses, businesses, and much more, allowing multiple sets of data to be displayed on a single map. Many industries and governments use GIS technology for analysis and decision making. For example, GIS data helps officials determine which streams are most in danger of being polluted.
It can also help a business decide where to locate a new store. History of Mapmaking Through the ages, maps have taken many different forms. The earliest maps were probably sketches made on the ground that showed the surrounding area. People native to the Marshall Islands used palm fibers to show wave patterns between islands in the Pacific Ocean. They used seashells to represent islands. Inuit fishermen in the Arctic carved pieces of driftwood to show coastal features.
It dates back nearly 14, years. The ancient Greeks are usually considered the founders of scientific cartography. Greek scholars knew the general size and shape of Earth, and they developed the grid system of latitude and longitude. Eratosthenes , who lived from about to B. Claudius Ptolemaeus, or Ptolemy , was an astronomer , mathematician , and geographer in the second century A. He brought mapmaking to a level of precision that would not be seen again until the fifteenth century.
He combined all his knowledge about the world into a book called Geography. In Europe during the Middle Ages , cartographers drew maps reflecting their religious beliefs.
These maps were generally simple and sometimes fanciful. The city of Jerusalem, holy to Jews, Christians, and Muslims, was sometimes placed in the center. The Nile and the Don meet in a single line to form the top of the T.
During these Dark Ages in Europe, Arab scholars kept scientific cartography alive. The more we pay attention to the device, the less we pay attention to our surroundings. Maps, on the other hand, ground you to your surroundings.
In this world, maps are the hero of the story and GPS will always be the sidekick. Maps give you a glimpse into how people understood their world at the time the map was created. Take a look at an old map. Of course, old maps show you the differences of what was there then and what is there now but the map also shows you how the mapmakers understood their world. Are there inaccuracies because of incorrect assumptions?
The cartographer and reason for the development of the maps can completely change how a map looks. Maps inspire you to think outside your world, to expand your horizons, and to take a look at the places you have been and the places you want to go to. Maps are the perfect conversation starter. Going on a trip can be a thrilling adventure but planning can also be an exciting part of your journey. This is why maps are often used as gifts to announce a trip even in the distant future.
Where a story happened is often as important as what happened in the story. To fully understand the full context of a story, you need to understand where the story exists in space and what relationship it has to areas around it. This is why some of the most popular complex stories over time include maps, like Lord of the Rings or Game of Thrones.
Maps make these stories richer by including layers of additional context. Maps inspire you to think outside your own world, to expand your horizons, and take a look at the places you want to go to. The world is a big place and even just acknowledging there are huge amounts of space in the world that you know nothing about can expand your mind.
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