gis midterm

Question 1

what is data

Answer 1

refer to facts, measurements, characteristics, or traits of an object of interest

Question 2

difference between data and information

Answer 2

data describes the object of interest, information is the knowledge resulting from data through analysis/collection/interpretation

Question 3

primary data

Answer 3

collected directly/on a firsthand basis

Question 4

secondary data

Answer 4

collected by someone else

Question 5

nominal data

Answer 5

name data; gives data a name but there’s not really a way to compare data. ex eye color, ethnicity, land use

Question 6

ordinal data

Answer 6

order data; gives ranks to data. ex very good, good, neutral, bad, very bad

Question 7

interval data

Answer 7

measures precise quantitative data. ex temp, year

Question 8

ratio data

Answer 8

measuring data by comparing it to the data collected elsewhere. ex population density

Question 9

database management system

Answer 9

a software package that allows for the creation, storage,
maintenance, manipulation, and retrieval of large datasets that are distributed over one or more files

Question 10

database

Answer 10

structured collection of data files

Question 11

flat database

Answer 11

spreadsheet where all data is stored in a single large table

Question 12

hierarchical database

Answer 12

organizes data into a “one to many” associations across levels (looks like a family tree)

Question 13

network database

Answer 13

similar connections to hierarchical but a top level with categories and bottom level with items that fit into the categories with lines going kinda everywhere

Question 14

primary key

Answer 14

represents the attribute (column) whose value
uniquely identifies a particular record (row) in the relation
(table). allows no duplicate values and cannot be null

Question 15

foreign key

Answer 15

The primary key corresponds to an identical attribute in a
secondary table

Question 16

origin table

Answer 16

where the primary key can be found

Question 17

destination table

Answer 17

where the foreign key can be found

Question 18

vector data model

Answer 18

uses points and their x-, y-coordinates to represent discrete
features

Question 19

raster data model

Answer 19

uses a grid and grid cells to represent continuous features
such as elevation and precipitation

Question 20

mental map

Answer 20

psychological tools that we use to understand,
relate to and navigate through the world where we live, work and play

Question 21

reference map

Answer 21

deliver location information to the map user

Question 22

thematic map

Answer 22

concerned with a particular theme or topic of interest

Question 23

dynamic map

Answer 23

changeable or interactive representations of the earth

Question 24

location

Answer 24

position on the surface of the earth

Question 25

nominal location

Answer 25

location by name. ex cudahy library

Question 26

relative location

Answer 26

location by some reference. ex next to the lakeshore

Question 27

absolute location

Answer 27

location by longitude/latitude or by address

Question 28

true north

Answer 28

where the axis of the earth’s rotation intersects the earth’s surface. where N and S poles are used as benchmarks

Question 29

magnetic north

Answer 29

the point on the surface of the earth where the earth’s magnetic fields converge. not exactly the same as true north/north pole

Question 30

grid north

Answer 30

the northward direction that the grid lines of latitude and longitude on a map, called a graticule, point to

Question 31

distance

Answer 31

The degree or amount of separation between locations and can be measured in nominal or absolute terms with various units

Question 32

map scale

Answer 32

factor of reduction of the world so it fits on a map

Question 33

representative fraction (RF)

Answer 33

describes scale as a simple ratio. The numerator, which is always set to one (i.e., 1), denotes map distance and the denominator denotes ground or “real-world” distance.

Question 34

written scale

Answer 34

uses words to show the relationship between the map and the landscape it depicts

Question 35

graphical scale

Answer 35

a symbol which appears as a small ruler printed on the margin of the map

Question 36

geographic coordinate system

Answer 36

location reference system for locating spatial features on the Earth’s surface

Question 37

latitude

Answer 37

angular distance north or south of the equator, measured from the center of Earth

Question 38

parallels

Answer 38

A line connecting all points along the same latitudinal angle

Question 39

longitude

Answer 39

measures the angle created between the point of interest, the center of the Earth at the same parallel of latitude, and a point on that latitude along the arbitrarily defined prime meridian

Question 40

equator

Answer 40

largest line of latitude, measured at 0 degrees

Question 41

great circle

Answer 41

divides globe into equal halves and passes thru center

Question 42

small circle

Answer 42

splits globe into unequal portions and doesn't pass thru center

Question 43

latitude based geographic zone

Answer 43

arctic, subarctic, midlatitude, subtropical, equatorial and tropical

Question 44

meridian

Answer 44

imaginary north to south lines (not full circles), denote west to east position from prime meridian

Question 45

prime meridian

Answer 45

meridian that all others are measured the distance from

Question 46

small-scale map

Answer 46

covers a larger geographic region such as the world

Question 47

large-scale map

Answer 47

covers a relatively small geographic area, such as a 7.5' quadrangle map

Question 48

datum

Answer 48

defines the position of the spheroid relative to the center of the earth

Question 49

why are datum important

Answer 49

it provides a frame of reference for measuring locations on the surface of the earth and a shift of the datum will result in the shift of positions of points

Question 50

NAD 83

Answer 50

horizontal and geometric control datum for the United States, Canada, Mexico, and Central America

Question 51

WGS 84

Answer 51

the current standard used in cartography, geodesy, and satellite navigation including GPS

Question 52

map projection

Answer 52

transforms the geographic coordinates on an ellipsoid into locations on a plane, produces a systematic arrangement of parallels and meridians on a flat surface

Question 53

planar projection

Answer 53

When the plane of projection taken is a simple 2-dimensional plane

Question 54

cylindrical projection

Answer 54

When a right circular cylinder is taken as a developable surface

Question 55

conical projection

Answer 55

When right circular cone is taken as a developable surface

Question 56

equal area projection

Answer 56

Area on a segment on the generating globe is truly preserved on the corresponding segment of the graticule

Question 57

conformal projection

Answer 57

Here the shape of a segment on the generating globe is truly preserved

Question 58

equidistant projection

Answer 58

Distance between any two points on the generating globe is truly preserved

Question 59

azimuthal projection

Answer 59

Here, the azimuth or bearing denoting the directions between any two points on the generating globe is truly preserved

Question 60

map projection parameters (6)

Answer 60

✓ standard lines (standard parallels and standard meridians), ✓ principal scale, ✓ scale factor, ✓ central lines, ✓ false easting, and ✓ false northing.

Question 61

mercator projection problem

Answer 61

poles size are largely exaggerated

Question 62

key elements used to make NY 9-11 basemap

Answer 62

city streets, properties, building footprints, transportation networks, rivers, and other waterways

Question 63

why was Leidner called to help after 9-11

Answer 63

oversaw the city's advanced GIS