GIS Midterm

Question 1

How do you select features? (3)

Answer 1

• manually by table or mapview
• select by attributes
• select by location (everything inside/outside/touching)

Question 2

Difference between join & relate

Answer 2

• A join is a means of appending a spatial layer and a data table (or two separate data tables) together based on a common attribute or field
• Table relates associate data tables without permanently appending them to the base dataset like in a Join

Question 3

A GIS has the following components ______, ________, ______.

Answer 3

• Computer Hardware and Software
• Spatial Data from the “Real World”
• Trained People

Question 4

Basic elements of vector data sets (3)

Answer 4

polygons
points
lines

Question 5

use of census data is an example of use of _____ data

Answer 5

systematic collection of data

Question 6

reference framework for x & y coordinates is called a ______

Answer 6

sfgsfgsdfgs

Question 7

difference between vector and raster data sets

Answer 7

raster:
satellite image, divide the area into arrays of cells and assign attributes to each cell; geographic location of each cell is implied by its position in the cell matrix. Accordingly, other than an origin poin

vector:
less complex than raster, store features as points connected by straight lines and assign attributes to the points/lines; Data can be represented at its original resolution and form without generalization

Question 8

during process of representing the ‘real world’ in GIS, 2 kinds of generalization are performed. Explain the difference between the 2.

Answer 8

Conceptual

cartographic generalization

Question 9

Explain spatial analysis method of overlaying a line and a polygon feature data set. Draw a sketch to support your explanation

Answer 9

• always combines attributes

- if a line and polygon combine – a line is the output feature

Question 10

geomatics

Answer 10

gathering, storing, processing, and delivering geographic information, or spatially referenced information.

Question 11

What is TIN?

Answer 11

Triangular Irregulated Network

• used for triangles
• describes a surface with irregular points

Question 12

Continuous fields

Answer 12

features that exist spatially between observations (elevation, precipitation)

best displayed as raster files

Question 13

Discrete objects

Answer 13

Individually distinguishable features that do not exist between observations (houses, roads etc.)

discrete objects can:

• overlap
• can be counted
• completely cover area under investigation

Question 14

In GIS, the 4th dimension is:

Answer 14

measurement

x, y, z, measurement

Question 15

What is GIS?

Answer 15

a computer based system for managing and visualizing geographic data and using this data to solve spatial problems

Question 16

5 M’s of GIS

Answer 16

Mapping
Measurement
Monitoring
modelling
management

Question 17

Components of a GIS (6parts)

Answer 17

Hardware
Software
Data
Procedures
People
Network

Question 18

2 fundamental ways to represent geography

Answer 18

discrete objects

continuous fields

Question 19

Geographic Phenomena (3)

Answer 19

Discrete
fuzzy
continuous

Question 20

data model

Answer 20

set of constructs for representing selected objects and processes for the real world on the computer digitally

Question 21

why is topology important?

Answer 21

• to test quality of a data set
• editing productivity
• optimizing queries

Question 22

Primary geographic data

Answer 22

sources captured specifically for use in GIS (direct measurement)

Question 23

Secondary Geographic data

Answer 23

data reused from earlier studies or from other sources

Question 24

remote sensing

Answer 24

technique to derive info about the physical, chemical, and biological properties of objects without physical contact

• spatial resolution
• temporal resolution
• spectral resolution

Question 25

GPS

Answer 25

global positioning system

- determines lat and longitude and elevation based on measuring position of satellites & velocity of light

Question 26

vector data collection

Answer 26

• Manual digitizing
• heads-up digitizing
• automated vectorization

Question 27

metadata

Answer 27

data about data

Question 28

Geometric transformation

Answer 28

• nodes
• vertices
• lines
• edges (topology)

Question 29

spatial analysis

Answer 29

adding value to data by using meaningful methods

- exploratory data analysis - graphic technique for exploring data

Question 30

vector data analysis

Answer 30

pattern analysis

- qualitative method to describe and analyze distribution pattern of spatial feautres

Question 31

locational quotient

Answer 31

index for comparing an areas share of an activity with the area’s share of some base phenomenon