geospatial analysis with raasa.ut.ee/tbilisi/01_intro_to _spatial_analysis_gis.pdf · • this is...
TRANSCRIPT
Geospatial Analysis with R
http://aasa.ut.ee/tbilisi
Geospatial Analysis with R
• Lecturer: Anto Aasa, PhD, senior research fellow
• Mobility Lab
• Department of Geography
• University of Tartu
http://aasa.ut.ee/tbilisi
http://mobilitylab.ut.ee/eng/http://aasa.ut.ee/tbilisi
http://aasa.ut.ee/tbilisi
EestiCapital: TallinnArea: 45000 km2
Population: 1.35 MCurrency: €
The aim & learning outcomes
• This is introductory course and it provides students with a diverse set of skills of spatial analysis in R environment.
• The aim for students is to understand and explore the benefits of using a non GUI approach for spatial analytics and statistics, based on the standard approaches in R & RStudio.
• Learning outcomes: After passing the course student– knows basic concepts, skills, and tools for working with the R scripting environment;– is familiar with set of practical R libraries for everyday scientific and professional GIS (Geographic
Information System) use;– is able to solve common data-related tasks using R in specific GIS projects and tasks;– is competent of using spatial and non-spatial data in order to answer a research questions;– knows how to conduct and automate different standard GIS related tasks that support clear documentation
of methods in the R scripting environment.
• These lessons assume no prior knowledge of the skills or tools. It is a hands-on teaching course, so the majority of this course will be independent work in front of a computer and working on exercises.
http://aasa.ut.ee/tbilisi
• All the materials are available via course webpage: http://aasa.ut.ee/tbilisi/
• Schedule: April - May, 2020
• The course consists of– lectures
– practical sessions
– additional reading
– independent tasks
– essay
http://aasa.ut.ee/tbilisi
http://aasa.ut.ee/tbilisi
Practical sessions:
1. Introduction to R
2. Data wrangling
3. Simple thematic maps
4. Physical map of Georgia & spatial queries
5. Mobile Data Collection Methods
6. Interactive plots & maps
7. …
http://aasa.ut.ee/tbilisi
Passing the course:
• To pass the course, students must
– solve independent task after every practical session based on previous materials. Results must be formatted as pdf-files and R-script files. Independent work make up 70% of the grade.
– write short essay (30% of the grade). Topic and more detailed description will be available here on May 11th, 2020.
• Deadline for all the submissions is May 15th 2020.
http://aasa.ut.ee/tbilisi
http://aasa.ut.ee/tbilisi
Introduction to spatial data analysis&
Geographical Information System –GIS
Spring 2020
Anto AasaMobility Lab
Department of Geography
http://aasa.ut.ee/tbilisi
Contemporary society:
• Digital revolution
• Information society
• Digital society, Digital Citizen
• Digital divide
• Innovation
• Mobility growth– Physical
– Virtual
http://aasa.ut.ee/tbilisi
Mobile society
• Compaction of time-space
– Virtual availability
• Widening of time-space
– Physical possibilities
http://aasa.ut.ee/tbilisi
What is geography?
• Physical geography • Human geography
http://aasa.ut.ee/tbilisi
Human geography deals with the study of people and their communities, cultures, economies, and interactions with the environment by studying their relations with and across space and place.Physical geography deals with the study of processes and patterns in the natural environment like the atmosphere, hydrosphere, biosphere, and geosphere.
Geography is everywhere!!!
Spatial relations!!!
Geographic information science
data structures and computational techniques to capture, represent, process, and analyze geographic information.
geographic information systems (GIS) =>software tools.
http://aasa.ut.ee/tbilisi
http://aasa.ut.ee/tbilisi
Time distance from London (1914)
Time distance from London (2016)
http://aasa.ut.ee/tbilisi
http://aasa.ut.ee/tbilisi
Physical distance isnot always euclidean…
Direct regular connections from Baltic capitals(2014)
http://aasa.ut.ee/tbilisi
61 35 35
Flights from Wuhan
http://aasa.ut.ee/tbilisi
http://aasa.ut.ee/tbilisi
1995putty http://aasa.ut.ee/tbilisi
Rapid changes
http://aasa.ut.ee/augsburg
0
100
200
300
400
500
600
700
800
19
80
19
85
19
90
19
91
19
92
19
93
19
94
19
95
19
96
19
97
19
98
19
99
20
00
20
01
20
02
20
03
20
04
20
05
20
06
20
07
20
08
20
09
20
10
20
11
20
12
20
13
20
14
20
15
20
16
20
17
No of Cars in Estonia, (x 1000)
Innovation speed
http://aasa.ut.ee/tbilisi
http://www.connectorsupplier.com/3g-versus-lte-versus-true-4g-speeds-huff-060413/http://aasa.ut.ee/tbilisi
Data: http://www.internetworldstats.com/stats.htm
578.5
1016.8
1405.1
2300.0
384.6500.7
582.4727.0
139235.8 322.4
453.0
51.1139.9
318.6522.0
248.2 273.1310.3
327.0
41.9 77 113.6 175.020.2 23.9 26.9 29.00
500
1000
1500
2000
2500
2008 2011 2014 2020
Internet users, %
Asia
Europe
Latin-America
Africa
North-America
Middle East
Oceania & Australia
http://aasa.ut.ee/tbilisi
Data: http://www.internetworldstats.com/stats.htm
15.3
26.2
34.8
53.648.1
61.3
70.4
87.2
73.678.6
86.9
94.6
5.3
13.5
27.5
39.3
24.1
39.5
52.4
70.5
21.3
35.6
48.1
69.2
59.5
67.5 72.1 67.4
0
10
20
30
40
50
60
70
80
90
100
2008 2011 2014 2020
Internet users, %
Asia
Europe
North-America
Africa
Latin-America
Middle- East
Oceania & Australia
http://aasa.ut.ee/tbilisi
Population living below national powerty line:
http://aasa.ut.ee/tbilisihttps://www.quora.com/Why-is-China-home-to-almost-none-of-the-poorest-10-of-humans
http://aasa.ut.ee/tbilisihttps://ourworldindata.org/grapher/life-expectancy?tab=map
Life expectancy, 2008
http://aasa.ut.ee/tbilisi
Big changes?
Internet traffic in 2007 vs traffic routes in ca 1930
http://aasa.ut.ee/tbilisi
Technological ground
• Fast development of mobile devices
– Display
– Global Navigation Satellite System (GNSS)
• GPS– A-GPS
• Galileo
• Glonass
• …
http://aasa.ut.ee/tbilisi
http://aasa.ut.ee/tbilisi
5110
http://aasa.ut.ee/tbilisi
Qualitative growth of Internet
http://www.urenio.org/2011/11/17/semantic-web-for-smart-cities/http://aasa.ut.ee/tbilisi
GIS functions
• Mapping and visualization;
• administration of geographical information;
• data collecting and updating;
• geographical analysis.
http://aasa.ut.ee/tbilisi
GIS in governance
GIS asdatabases
DecisionSupport systems
Modelling & SimulationActivities
PublicParticipation and
InformationAccess
http://aasa.ut.ee/tbilisi
Geographic information system (GIS)
• Mutually related complex of software and data
– Watching geographical information,
– Administration of geographical information,
– Analysis of spatial relationships and patterns,
– Modelling of spatial processes.
http://aasa.ut.ee/tbilisi
GIS
• Hardware
• Software
• Database
– Geographical space
– Theme (attributes)
• Operations
• Human resource
http://aasa.ut.ee/tbilisi
History
• First person who placed different layers on top of each other?
http://aasa.ut.ee/tbilisi
Cholera deaths in London
John Snow 1854
http://aasa.ut.ee/tbilisi
http://aasa.ut.ee/tbilisi
History• 1963: first nation-wide GIS - Canada• 1966: first raster-GIS• 1972: first civil use remote sensing satellite Landsat 1 • 1978: first satellites of NAVSTAR (development of GPS technology)• 1979: first vector-GIS –ODYSSEY GIS• 1981: Esri ARC/INFO • 1986: MapInfo – first desktop GIS• 1994: beginning of standardization of spatial data and infrastructure
(OpenGIS consortium)• 1996: first Internet based GIS products• 1996: first Internet based map service MapQuest• 2000: over 1 million professional GIS users in world, over 5 million
„average“ GIS users• Today: everyone can „GIS“
http://aasa.ut.ee/tbilisi
Area of use
• Land survey, cartography• Logistics• Aviation• Real estate• Military forces• Trade• Local authority• Science• Infrastructure management• …• Spatial planning
http://aasa.ut.ee/tbilisi
Important factors for spatial analysis
• Location data
• Attribute data
• GIS
http://aasa.ut.ee/tbilisi
Spatial databases & GIS
• Location: spatial vs descriptive?
– 41°40′09″N 44°57′17″E
– Tbilisi airport
• Relation between objects
– Distances
– Patterns
– Relationships, causality
http://aasa.ut.ee/tbilisi
Location:
• Descriptive
• Spatial
• Network
http://aasa.ut.ee/tbilisi
• Everything, what happens in real world has geographical coordinates
– X
– Y
– Z
– time
• (also in virtual space)
http://aasa.ut.ee/tbilisi
Location
• Map and database must be in same projection and datum
– Datum – model of the earth
– Projection – curved surface to flat plane
http://aasa.ut.ee/tbilisi
• Earth is not ideal sphere but geoid (potato-shaped)
– Earth model: ellipsoid
• Map projection – method of representing the surface of Earthon a plane
– All map projections distort the surface in some fashion
• Error minimization
http://aasa.ut.ee/tbilisi
Representation of spatial data
• Real world is too complex
• Simplified models
– Maps
– Cartography
http://www.colorado.edu/geography/gcraft/notes/datum/datum_f.html
Modelling the real world
• Discrete objects
• Continuous fields
Visualization of invisible objects / phenomenas (Augmented, Mixed Reality)
Distortions
– area,
– direction,
– scale,
– distance.
http://blog.perrygeo.net/2005/12/11/tissot-indicatrix-examining-the-distortion-of-2d-maps/
Model accuracy
Augmented reality
http://aasa.ut.ee/tbilisi
Representation of geoinformation in GIS
• objects
– points,
– lines,
– polygons;
• raster;
• attributes.
http://aasa.ut.ee/tbilisi
VectorPoint
Line
Polygon
Shp-layer:
http://aasa.ut.ee/tbilisi
Raster
slope Elevation shading Population density
ortophoto Landuse concentration
Lat | Lon | Value26.466 |58.478 | 165 … | … | …
http://aasa.ut.ee/tbilisi
Vector layer
• Attributes table:
– Rows: map objects
– Columns: attributes
– Queries (SQL)
http://aasa.ut.ee/tbilisi
• Layer based model:
– One theme for every layer
– One data type for every layer (point, line, polygon, raster)
Elevation
http://aasa.ut.ee/tbilisi
Perception
• Use of color
– Traditions of visualising certain object types
• orientation
• Symbols
• Colors
http://aasa.ut.ee/tbilisi
Perception
http://aasa.ut.ee/tbilisi
http://www.rpdms.com/satillusion/index.html
• Map (data) scale
– the ratio of a distance on the map to the corresponding distance on the ground (e.g. 1:400 000)
• Generalization
– Simplifying of objects
Measurements accuracyModel accuracyAmount of data
http://aasa.ut.ee/tbilisi
Generalization
http://aasa.ut.ee/tbilisi
GIS output
• Table
• Graph
• Report
• Thematic map
• Something else?
What is the aim?
http://aasa.ut.ee/tbilisi
Internet maps
• Open Street Map
• Google Map
• Bing Map
• …
http://aasa.ut.ee/tbilisi
Creating GIS
• Reality model (description of the real world)
• Data model (database structure and technology)
• Representation model (rules for data representation)
– e.g. Roads on top of rivers
http://aasa.ut.ee/tbilisi
Management of spatial data
• Raster model
– Rectangular regular grid of pixels
• Vector model
– Points, lines, polygons (functions determining the shape and form ofobjects)
http://aasa.ut.ee/tbilisi
Processing of geographical data
• Processing of the initial data for achievement of goals
– Queries (response to relevant conditions)
– Spatial analysis (description of place, attribues and relationshipsbetween them)
http://aasa.ut.ee/tbilisi
Quality of spatial data
• Completeness (missing, redundant data)
• Consistence
• Location correctness
• Up-to-date
• Thematic correctness
http://aasa.ut.ee/tbilisi