introduction mapping your tracks - concepts and designs

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Faculty of Geoinformation Science and Earth Observation

Mapping your tracks - concepts and designs

Menno-Jan Kraak, Rein Ahas, Raivo Aunap

• Introduction

• Spatial mobility and movement trends

• Challenges

• Towards solutions

• What remains to be done

Mapping your tracks, concepts and designs

• UNCHR refugee flows

Movement basics

Afganistan

ZambiaZimbabwe

Yemen

AlgeriaAlbania….

….….

Afganistan

Zambia

Zimbabw

e

Yemen

Algeria

Albania

….

….

….

Afganistan

ZambiaZimbabwe

Yemen

AlgeriaAlbania….

….….

Afganistan

Zambia

Zimbabw

e

Yemen

Algeria

Albania

….

….

….

Afganistan

ZambiaZimbabwe

Yemen

AlgeriaAlbania….

….….

Afganistan

Zambia

Zimbabw

e

Yemen

Algeria

Albania

….

….

….

Afganistan

ZambiaZimbabwe

Yemen

AlgeriaAlbania….

….….

Afganistan

Zambia

Zimbabw

e

Yemen

Algeria

Albania

….

….

….

Afganistan

ZambiaZimbabwe

Yemen

AlgeriaAlbania….

….….

Afganistan

Zambia

Zimbabw

e

Yemen

Algeria

Albania

….

….

….

13 years

Afganistan

ZambiaZimbabwe

Yemen

AlgeriaAlbania….

….….

Afganistan

Zambia

Zimbabw

e

Yemen

Algeria

Albania

….

….

….

from (200)

to (200)

7.280.000 flows

refugeesasylum seekers

returned refugeesinternally displaced

returned i.d.stateless persons

various

7 types

(http://popstats.unhcr.org/)discrete[20 years hurricane paths; Turdukulov and Restios, 2013)continuous

• Continuous In Physical Geography flow (wind, currents etc) is a movement not necessarily clearly marked with purpose, origin and destination

• Discrete In Social Geography one could argue there is always a kind of known origin and destination, but the abstraction level and scale will determine its accuracy

Movement - Flow

Continuous flows: wind

[http://hint.fm/wind/ Martin Wattenberg and Fernanda Viegas]

Continuous flows: sea currents

.

https://svs.gsfc.nasa.gov/3820

Flows (refugees)

http://www.lucify.com/the-flow-towards-europe/

Discrete Movement

trajectoriesorigin - destination

• Movement or spatial mobility is about change in position during a selected time unit (object, path, its speed, duration, distance) • locational details are known in between A and B (trajectories

collected via GPS). • only start and end locations are known (origin-destination (OD)

matrices collected via census)

• Mobility • Spatial mobility versus social mobility

Discrete movement

• Location

• path, trajectory, direction

• Attribute

• qualitate, quantitative

• Time

• implicitly (path of path)

Characteristics

Flows

flow maps flow charts (Migration; http://2.bp.blogspot.com/-nRCZfaEDAzE/UjxWPayj-gI/AAAAAAAALqY/GVi5snz4AmY/s1600/cosmograph-in-excel.gif)

(Migration; Minard, 1862)

(Cover Mobile Tartu 2016, Anto Aasa)

• Movement, spatial mobility and mobilities have a definite temporal dimension

• Temporal scale of movements and mapping was featured by famous Swedish geographer Thorsten Hägerstand (1952, 1969) • space time cube, with its paths, stations, and prisms. • constraints limiting movements in space and time

Time

Time

space time cube: paths and stations

(Tallinn commuters; Kveladze, 2015)(Orienteering; Kraak et al, 2014)

Permanent migration • permanent change in residence • simple origin-destination movement

Temporary migration • short term mobility with no change in permanent residence • clearly distinguishable temporal cycle (diurnal, weekly or seasonal)

and spatial cycle (home-work; home-second home, etc)

Migration

Migration

temporary(Commuters Estonia; Novak et al, 2013)permanent(Shifting center of population; Bureau of the Census http://www.census.gov/geo/reference/pdfs/cenpop2010/centerpop_mean2010.pdf)

• Theory: the revolution of ICT is driving virtual mobility without the need for physical travel

• Practice: virtual communication and virtual mobility is forcing in most of cases also physical activity – person with more communication has more travel

Virtual mobility

Virtual mobility

Virtual Physical(Social networks; http://danielmclaren.net/node/77) (Network Iceland Air; http://airinsight.com/wp-content/uploads/2014/09/icelandair-52013-route-map.jpg

• Volume • large data collection; what is large is defined by context

• Variety • heterogeneous nature of the data

• Variability • for the GI community this refers to difference spatial and

temporal scales as well as multivariate character of attributes • Velocity

• the update cycle, the generation of new data, the availability of data from ’unintentionally collected data, crowd sourced data

• Veracity • the data quality, being more diverse then ever

Big Data ( “just too much data” )

Big Data

(Migration in France; Klein et al, 2009)

Flows: Need for other types of mobility maps to deal with individual tracks as well as large volumes of aggregated data

Intermezzo - Points of attention

Time: Need to include the temporal dimension in the graphic representation

Migration: Need for graphic representations that map regular and irregular movement cycles in space and time

Big Data: Need for mapping tools that are be able to deal with huge data amounts of diverse and fuzzy data sources

Towards a solution

Geocomputation: algorithms that deal with clutter, are able to aggregate, etc

Alternative Representations: 3d flow maps, cartograms, chord diagrams, tree maps, prism maps, etc

Interaction: visualization strategies to zoom, filter, select, mouse over, linked views, etc

Design: optimization of symbology, colors, arrows, dimensionality, etc

Geocomputation

(Edge bundling; Phan et al, 2005)

(Forced direct edge bundling; Holten et al, 2009)

(Migration from California; Tobler 1987)

Design

(Call events in antennae locations when visiting Saarmaa; J. Raun, 2015)

Interaction: detail and overview

(DOSA, a multivariate network explorer ; Elzen et al, 2014)

Alternative approaches: chord diagram

(Migration between the 25 municipalities of the province of Overijssel; http://circos.ca)

Alternative approaches: tree maps

(Spatially ordered treemaps; Wood et al, 2010)

Interaction: origin / time / destination

(Flowstreets; Boyadin, 2011)

• Design and big data

• Dashboards and summary maps

• 3D flow maps

• O-D matrix visualizations

Future projects

III & V CorpsPolish Lancers

first rivercrossing II Corps Imperial

Guard old NapoleonImperial Guardyoung

I & IV Corps IX Corps

November 26 November 27 November 2800:0000:00 06:00 12:00 18:00 00:0006:00 12:00 18:00 00:0006:00 12:00 18:00

Infantry BridgeArtillery Bridge

8350 4300 5945 2225 2475 13250

Time

Numberof troops

a)

November 27 - 13:00

b)

A. II Corps

B. III & V Corps

C. Imperial Guard (old)

D. Imperial Guard (young)

E. I & IV Corps

F. IX Corps

A B C D E F

1000018800 13200 110002200

5945

2400

930054003400

3100

48802200

54005500

8350

3000

7800

49001500 2200

70003000

2200

Chambray Wilson Fain Gourgaud

Size of the French armyestimates by:

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