Study Guides (238,078)
Canada (114,909)
Geography (252)
GEO 221 (4)


5 Pages
Unlock Document

Ryerson University
GEO 221
Steven Swales

GEO 141 Test#1 02/10/2011 18:27:00 ← What is GIS ? • Geographical Information Systems ← Why use GIS? • To create and analyze maps, photographs, satellite images ← Why analyze them? • To see information (data) on a visual form to identify relationships, trends. ← GIS can be used for: • Choosing the most effective way to build/take down buildings • Protecting forestry • Buffer: customer spotting (taking postal codes) ← ← Distance Decay: The further away the data from a location the less amount of data. It is a function that represents the way that some entity or its influence decays with a distance from its geographical location. ← ← Ecological Fallacy: a problem associated with the “modifiable areal unit problem” that occurs when it is inferred that data for areas under study can be applied to individuals in these areas. The assumption that an individual from a specific group or area will exhibit a trait that has predominant to the group as a whole. ← ← Raster Data Model: system of tessellating rectangular cells in which individual cells are used as building blocks to create images of point, ling, area, network, and surface entities. A representation of the world as a surface divided into a regular grid of cells. Raster models are useful for storing data that varies continuously, as in an aerial photograph, a satellite image, a surface of chemical concentrations, or an elevation surface. ← ← Choropleth Map: a thematic map that displays a quantitative attribute using ordinary classes. Areas are shaded according to their value and a range of shading classes. A thematic map in which areas are distinctly colored or shaded to represent classed values of a particular phenomenon. ← ← Vector Data Model: a spatial data model using two-dimensional cartesion (x,y) co-ordinates to store the shape of spatial entities. A representation of the world using points, lines, and polygons. Vector models are useful for storing data that has discrete boundaries, such as country borders, land parcels, and streets. ← ← Intervening Opportunities: The existence of a closer, less expensive opportunity for obtaining a good or service, or for a migration destination. Such opportunities lessen that attractiveness of more distance places. ← ← Census Tract: A small, statistical subdivision of a county that usually includes approximately 4,000 inhabitants but may include from 2,500 to 8,000 inhabitants. A census tract is designed to encompass a population with relatively uniform economic status, living conditi
More Less

Related notes for GEO 221

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.