GISFORAPPLIEDECONOMICS

VisualizationtoolsandVectorTransformation(II)

JuanCarlosMuñoz-MoraUniveristatPompeuFabra

Nov2016

juancarlos.munoz@upf.edu

ROADMAP1. Commentsonthereplicationfromprevioussession2. AdditionalconceptsinVectorTransformation3. ConceptsinVectorTransformation(II)

BufferDistances

4. Bufferanddistancesinaction5. ReplicationDell()

REPLICATIONPREVIOUSSESSION

Desktopsolution?ReplicationpyQGISReplicationStandalone

DESKTOPSOLUTIONS(ANIDEA)1addnewvariableattribute2makeintersection3exportdatatoR(csv)4identifyrepeatedunion5joindatafrom

outside

ADDITIONALCONCEPTSINVECTORTRANSFORMATION

UNION

Inshapely(Standalonesolution)

InpyQGIS

a.union(b)

processing.runalg('qgis:union', input, input2, output)

DIFFERENCE

Inshapely(Standalonesolution)

InpyQGIS

a.difference(b)

processing.runalg('qgis:difference', input, overlay, output)

SYMMETRICDIFFERENCE

Inshapely(Standalonesolution)

InpyQGIS

a.symmetric_difference(b)

processing.runalg('qgis:symetricaldifference', input, overlay, output)

SPATIALJOINOverlappingNearbyjoin

DESKTOPSOLUTIONS(PLUGINS)mmqgisspatialjoin

ANYIDEA(INTUITION)HOWCANWEIMPLEMENTTHISINPYTHON/PYQGIS?

Inshapely(Standalonesolution)

InpyQGIS

## ---- For Polygons## Option 1 - object.contains(other)## Option 2 - at the borderobject.touches(other)## Option 3object.within(other)## --- For Linesobject.crosses(other)object.disjoint(other)

processing.runalg('qgis:joinattributesbylocation' , target, join, predicate, summary, stats, keep, output)

CONCEPTSINVECTORTRANSFORMATION(II)

BUFFERThisoperationcreatesapolygonaround

theobjectataspecifieddistance.

Neighborhood(averyrusticdefinition-why?)Identifyspilloversoftreatments

,Peereffect

Alternativewaystodefinetreatment

DISTANCES

Miguel&Kremer(2004) deMeletal.(2008)

Conley&Udry(2010)

Muehlenbachsetal.(2015)

Proximity(veryrude)Buildinstruments(Validity!)

Moreonlocationasainstrumentsee

Whatisthedifferentwithbuffferapproach?

Oster(2012)Nunn(2008)

Gibson&McKenzie2007

source:ArcGISManual

U.S.commercialairports,2008greatarcsandsymbolmapshowVoronoi

Reportamaperror

PompeuFabraUniversity

Madrid,SpainMoreoptions

Signin

©2016Google-Mapdata©2016GeoBasis-DE/BKG(©2009),Google,Inst.Geogr.Nacional TermsofUse

ThreemodelsoftheEarthtocalculatedistances:

FlatplaneSphericalEllipsoid

FLATPLANE-EARTHASAFLATPLANEEuclideandistance(Pythagoreantheorem )

whatifweuseunprojectedcoordinates?units

+ =a2 b2 c2

SPHERICAL-EARTHASAPERFECTSPHEREGreatcircledistance(Haversineformula-decimalsdegrees)

ELLIPSOID-EARTHASANON-PERFECTSPHERE

Greatcircledistance(Vincentyformula-decimalsdegrees)

But,whataboutifwewouldliketotakeintoaccountroads?

Wewilldiscussitonthelastsession!

CONCEPTSINVECTORTRANSFORMATION(II)

INACTION

DavidYanagizawa-Drott

QuarterlyJournalofEconomics,2014,129(4),pp.1947-199

PROPAGANDAANDCONFLICT:EVIDENCEFROMTHERWANDAN

GENOCIDE

Theroleofmassmediaintimesofconflictandstate-sponsoredmassviolenceagainstcivilians.

METHODRTLMtransmittersandradiopropagationsoftwareradiocoveragewithineachvillage.Casuallink receptiongeneratedbyRwanda'shighlyvaryingtopography

MAINFINDINGBroadcastsledtomoreviolenceduringthegenocide.

participation(10%oftotal-51,000persons)spillovereffectsinmilitiaviolence

→

→

↑↑

Inadditiontoviolencebythemilitary,attacksandmassacresconductedbylocalmilitiasgroupsandordinary

civilianscontributedtoadeathtollof0.5–1.0milliondeaths(DesForges,1999;Straus,2004;Verwimp,2006).

TimothyG.ConleyandChristopherR.Udry

AmericanEconomicReview2010,100:1,35–69

LEARNINGABOUTANEWTECHNOLOGY:PINEAPPLEINGHANA

TheroleofsociallearninginthediffusionofanewagriculturaltechnologyinGhana. Dofarmerslearnfrom

theirpeers?

MAINFINDINGSFarmersadjusttheirinputstoalignwiththoseoftheir

informationneighborswhoweresurprisinglysuccessfulinpreviousperiods.

DATAGeo-locatedpanelhouseholdsurveys(every6weekin1996-

98)in3villagesofsouthernGhana

→

NEIGHBORHOODMETRICResponseto"Haveyouevergoneto__foradviceabout

yourfarm?"

EMPIRICALSPECIFICATION

INDEXOFGOODNEWSINPUTLEVELS

Standarderrors:calculatedbyConley(1999)

SPATIALREGRESSIONDISCONTINUITY

DESIGN(fewwords)

WHATISDIFFERENT?Usingboundariesascutoff

lines(set)Indicator-Score-coordinatestwo-dimensions

Further

→

Keele&Titiunik2014

SomeapplicationsinEconomics

DELL(2010) MICHALOPOULOS&PAPAIOANNOU(2014)

NathanNunn

TheQuarterlyJournalofEconomics(2008)123(1):139-176.

(GISstrategyreplication)

THELONG-TERMEFFECTSOFAFRICA'SSLAVETRADES

THEPAPERCanpartofAfrica'scurrentunderdevelopmentbeexplained

byitsslavetrades?

DATASlavesexportedfromeachcountry

fromeachportofAfricaEthnicityofasampleof100,00+slavesEthnichomelandinAfrica

REDUCEDFORM

GDPpercapitaincountry in2000

#ofslavesexported1400-1900fromcountry

Landsurfaceareaofcountry

Controls

= α + β ln( ) + +yiexporti

areaiX ′

i εi

yi i

exportsi

i

areai i

X ′i

DISTANCEASINSTRUMENT

EXCLUSIONRESTRICTION-LOCATIONOFSLAVEPORTS

climatesuitabilityofplantationcrops/locationofminesnotaffectedbythedistancetoAfricaDistancetoslavemarkets Distancetoothereconomicopportunities

≠

FIRSTSTAGE

where,

Distancetonearestslavetradecenters

ln( ) = δ + Ω + +exportsi

areaiD′

i X ′i μi

=D′i

RESULTS(FIRSTSTAGE)

RESULTS(SECONDSTAGE)

REPLICATIONPLANDistancetotheSlaveTradeCenterFromeachcountrytilltheAtlanticborder

REPLICATEITSINSTRUMENTDistancetonearestslavetradecentersPLANARE

TIPSFORPYQGISInpyQGIS

processing.runalg('qgis:union', input, input2, output)

TIPSFORPYQGISGettingthecentroids

Featurebyfeature

processing.runalg('qgis:polygoncentroids', input_layer, output_layer)

for f in layer.getFeatures(): pt = f.geometry().centroid().asPoint()

DistanceMatrixprocessing.runalg('qgis:distancematrix', input_layer, input_field, target_layer, target_field, matrix_type, nearest_points, distance_matrix)

FORNEXTSESSIONInstallthefollowinglibraries

rasteriorasterstats