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GIS Cookbook: Glossary
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Address matching - Address matching is the process of assigning x, y coordinates to addresses so they can be displayed as points on a map. This process allows two or more data files to be related using a common address field.
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Attribute - A trait or characteristic of a feature on a map. For example, attributes of a county may include its area, perimeter, name, total population, etc. Attributes can be viewed through the attribute table such as within a shapefile.
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Attribute table - A table that is attached to a data layer that contains many characteristics of a feature on a map. The table is made of columns and rows where the columns represent values or description for different attributes and each row represents a different feature. For example, the attribute table for a layer of points that represents elementary schools may have columns labeled “number of students,” “number of teachers,” or “distance from police station,” and each row would represent a different school having values for each column.
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Buffer - A buffer is a region around a geographic area (point, line or polygon). Buffers are usually used for proximity analysis. Buffers can be created in both ArcView, and ArcInfo
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Cartographic Elements - One of the building blocks that make up a map from which all maps must be assembled. (Clarke, 2001) See Figure below.
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Database management system - A DBMS is a collection of computer programs and software for organizing the information in a database. A DBMS supports the structuring of the database in a standard format and provides tools for data input, verification, storage, retrieval, query, and manipulation.
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Dissolve Barriers - An option in the buffer wizard to treat a soon to be created buffer as either one object or several
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Feature - A digital representation of something in the real world. For example, dots or points on a map layer may represent the location of schools, a line may represent a river, and a polygon may represent the outline of an area such as a county.
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Feature class - Feature classes are classifications and representations of geographic features and supporting data in coverages. Feature classes represented as geographic features include points, arcs, nodes, route-systems, routes, sections, polygons, and regions. They can also store annotations, dimensions, x, y, z coordinates, and addresses. Feature classes can be found in a feature dataset where the same coordinate system can be shared and organized into a geometric network that can maintain topological relationships between its feature classes. Feature classes can also exist independently in the geodatabase.
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Feature dataset - A feature dataset is a collection of feature classes sharing the same spatial reference. These feature classes can take part in topological relationships with each other such as in a geometric network. Feature datasets can also store object classes and relationship classes.
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Geocoding - Geocoding is also commonly known as address matching. It is the process of creating a spatial description of a place, such as a point feature from a nonspatial description of that place, like a street address. Recorded x, y coordinates of a location are cross-referencing between a standard reference grid and non-geographic data such as addresses or zip codes to accurately map that location. In order to geocode, a geocoding service must first be defined.
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Geocoding service - A geocoding service defines a procedure for changing non-spatial descriptions of places into spatial descriptions. These services define paths to reference data, rules for standardizing alphanumeric descriptions of locations and matching them to the reference data, and parameters for reading address data and creating output. Geocoding services can be used to find individual addresses and to geocode tables of addresses. Geocoding tables of addresses allow a user to review and rematch feature classes and shapefiles.
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Geodatabase - Geodatabase stands for geographic database and stores geographic information inside a DBMS or database management system. A geodatabase supports advanced capabilities such as geometric and logical networks, true curves, complex polylines, and user-defined features. They are the modern equivalents of shapefiles and coverages stored in a DBMS. Geodatabases support large collections of objects in a database table and features with geometry. The feature classes and tables contained in geodatabases can be related to one another. In order to define the relationships between objects in a geodatabase, a relationship class must first be created. These relationships allow someone to use attributes stored in a related object to symbolize, label, or query a feature class.
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Geoprocessing - Geoprocessing embodies GIS operations, which include data conversion, geographic feature overlays, topology processing, coverage selection and analysis.
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Graduated Color - Graduated Color Features are features that are displayed with the same symbol type, but the colors on each represent the progression of values for a data attribute you specify
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Identify tool - The Identify tool lets you display the attributes of features on a view by clicking on them with the mouse. Attributes of all features located at the same point are displayed
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Layer - A collection of similar geographic features within a particular area that is defined by the map display. An example of a layer may be a map of only rivers within a state. There are different types of layers (also called data layers) such as shapefiles, coverages, or grids. These data layers show different types of representations of the real world and can be accessed and managed like other types of data within your database.
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Layout - A layout is a map that lets you display views, charts, tables, imported graphics, and graphic primitives. The layout is used to prepare these graphics for output from ArcView or ArcInfo. A layout defines what data will be used for output and how they will be displayed
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Legend - Translates the symbols on the map into words by locating text and the symbols close to each other in the page coordinate space. (Clarke, 2001)
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Legend Editor - A menu that allows you to choose the legend type for a specific theme. (graduated color, graduated symbol, single symbol, unique value, or chart). It also allows you to change the font, style, fill color, thickness of the points, lines or areas of your theme
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Locator Map - Also known as an inset map, is an enlarged or reduced map designed to put the main map into geographic context, or to enlarge the area of interest whose level of detail is to specific for the main map scale. The locator map should have all the cartographic elements but at a highly simplified format. (Clarke, 2001)
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Neatline - Is the visual frame for the map. It is a border around the entire page. It usually provides the basis for a the page. (Clarke, 2001)
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Object - A set of points, lines or polygons in a spatial database that represent a real-world entity. These can be manipulated, and counted in a GIS, and are represented in a GIS as shapefiles
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Query - A question or request used for selecting features. A query usually appears in the form of a statement or logical expression. It can contain a field, an operator, and a value.
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Relational database management system - A database management system with the ability to access data organized in tabular files that can be related to each other by a common field. An RDBMS can recombine the data items from different files, providing powerful tools for data usage. RDBMS services include validation rules, relationships, and topological associations.
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Rematching - A re-geocoding of a subset of addresses (which can included all or fewer than the original set of addressed) of features in a geocoded feature class. Rematching is done when partial or unmatched records result when geocoding address with errors such as misspellings or other data entry errors.
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Scale - The distance ratio measured on a map to that distance measured on the ground between the same two points. For example if one cm on a map equals 1,000,000 cm in the real world the map scale would be 1:1,000,000. This scale of 1:1,000,000 on the map would be considered small scale compared to a map with a scale of 1:1,000
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Scale Bar - Is a visual expression of the relationship between ground coordinate space and that if the map page space. (Clarke, 2001)
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Select feature tool - The Select Feature tool lets you select features with the mouse by pointing at them or by dragging a selection box over them. Features that fall partly or wholly inside the box you define will be selected. Features will be selected from all of the currently active themes
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