lecture 2

Question 1

what is geographic information

Answer 1

data with real world location
the where and what

Question 2

key attributes to maps
what are some things to keep in mind ab maps

Answer 2

one point in time
fixed perspective
macro n micro
fine to coarse

Question 3

what is analogue to digital conversion

Answer 3

real world characteristics turns to alpha character or string of numbers so comp can understand better

Question 4

hard copy maps characteristics

Answer 4

one point in time, need to reprint to update info
scale and perspective fixed
tends to be scaled down, using analogues to represent things (blobs, lines, squares)

Question 5

digital copy map characteristics

Answer 5

projection not fixed, can change perspectives
roads represented as coordinates w additional infornation w
can be readily updated

Question 6

3 things required to convert irl info into comp

Answer 6

coordinates, projection, datum

Question 7

what is a coordinate

Answer 7

segmented earth into scalar unities to define location

Question 8

2 kinds of coordinate systems in nz

Answer 8

nztm2000 (made in 2000 info given in local datum. easy to measure)
wgs584 (world geographic information) uses latitude and longitude

Question 9

why the coordinate systemnused in nz not good for other larger countries

Answer 9

cuz its too large. nz can be more specific

Question 10

what is a projection

Answer 10

3D globe represented in a 2D map

Question 11

what kinds of distortions

Answer 11

distance from one feature
direction from one feature
scale from one feature
shape of a feature

Question 12

what are datums

Answer 12

the mathematical way of representing x y and z on a globoid location

Question 13

whats a geoid

Answer 13

the potato earth

Question 14

how is a geoid calculated

Answer 14

using gravity

Question 15

whats a spheroid

Answer 15

the theoretical perfect circle where centre of earth is (0,0,0)

Question 16

whats geocoding

Answer 16

determining geographic coordinates for place names, street address and codes

Question 17

what is geo referencing

Answer 17

taking aerial image and relating it to real world coordinates

Question 18

what is data model

Answer 18

conceptual understanding of how information is categorised and organised (why)

Question 19

whats a data structure

Answer 19

how data is translated from real world into digital world

Question 20

two ways of thinking ab world (data model)

Answer 20

as an object
as a field

Question 21

whats vector good for

Answer 21

objects thibgs
can be stacked w attribute table

Question 22

raster good for

Answer 22

feild (grid w same geographical feature)

Question 23

two ways u can measure gis

Answer 23

categorical and numerical

Question 24

whys numerical good in gis

Answer 24

comforms to digital archetecture, easier for computers to digest, can preform maths on data

Question 25

what are the 4 categories of numerical data

Answer 25

nominal, ordinal, interval, ratio

Question 26

nominal measuremnet

Answer 26

similar to id
does not have intrinsic or relative value compared to other

Question 27

what is ordinal measurement

Answer 27

order is importwnt but does not suggest anything further
we do not know the imbetween

Question 28

what is interval measurement

Answer 28

gap feom one to another matters but does not start from 0
therefore you cannot divide but can subtract

Question 29

why is radio measurement

Answer 29

were distance from one another matters as well as it starts feom 0
therefore you are able to divide and subtract from data