¯ NAD 1983 StatePlane Texas Central FIPS 4203 (US Feet) · PDF file¯ 01.5 30.75 Miles NAD 1983 StatePlane Texas Central FIPS 4203 (US Feet) Legend Number of Units Less than 50 51

Evaluating access to jobs via transit from disparate neighborhoods CliffordKaplan‐GISforWaterResources2014,TermProject

Manor Corridor

Burnet Corridor

Riverside Corridor

Esri, HERE, DeLorme, MapmyIndia, © OpenStreetMap contributors, andthe GIS user community

Created by: Cliff Kaplan | Fall 2014Data Sources: BBC Consulting; Investor Incentives;

Travis County Appraisal District; Housing WorksNAD 1983 StatePlane Texas Central FIPS 4203 (US Feet)¯ 0 1.5 30.75 Miles

Legend

Number of Units

Less than 50

51 - 100

101 - 200

More than 200

Manor Corridor

Burnet Corridor

Riverside Corridor


Created by: Cliff Kaplan | Fall 2014Data Sources: CapMetro

NAD 1983 StatePlane Texas Central FIPS 4203 (US Feet)¯ 0 2.5 51.25 Miles

Legend

CapMetro bus lines

Manor Corridor

Burnet Corridor

Riverside Corridor


Created by: Cliff Kaplan | Fall 2014Data Sources: http://.onthemap.ces.census.gov,

U.S. Census BureauNAD 1983 StatePlane Texas Central FIPS 4203 (US Feet)¯ 0 2 41 Miles

Legend

Jobs!( 20 - 300

!( 301 - 1000

!( 1001 - 5000

!( More than 5000

1

Summary

For this term project I set out to design and conduct an easily replicable

geospatialanalyticalmethodtocompareurbancorridors in termsof theaccess to

low‐incomejobsviapublictransitthateachcorridorhas.ThemethodIdeviseduses

nationallyavailablejobsdata,publiclyavailabletransitdatathatisgenerallyeasyto

find incitieswith transit systems,andacollectionofhousingdatasets thatwere

moredifficulttoassemble,butthatwouldbenecessaryforanyonewhoisworking

geospatiallyonaffordablehousing issues tohave.Theanalyticalmethod relieson

simpleGIS skills and is easilymodified according to the level of specificity in the

data(e.g.,numberofbuildingsversusnumberofunits,andwhetherornot transit

headwaydataisavailable).

Conducting the analysis for three urban corridors in Austin, TX—Manor

Road, Burnet Road, and East Riverside Drive—I found that low‐wage jobs (by

definition the relevant class of jobs for people living in affordable housing,) are

twiceasaccessiblefromtheBurnetcorridorastheyarefromtheRiversidecorridor

andnearlyfourtimesasaccessibleastheyarefromtheManorcorridor.Affordable

housing in the Manor corridor has 76% less accessibility to jobs than does the

affordable housing in the Burnet corridor, although the actual number of jobs

reachable from the Manor corridor is only 33% less than the number reachable

from the Burnet corridor. The differences in accessibility are due not only to the

placesthebusesgo,buttowheretheaffordablehousingisinrelationtothenearest

buslinesandhowoftenthebusescome.

2

Contextforthisproject

The Green and Inclusive Corridors project is a U.S. Housing and Urban

Development(HUD)fundedprojectledbyDr.ElizabethMuelleroftheCommunity

andRegionalPlanningdepartmentattheUniversityofTexasatAustin.Theproject’s

objective is to design and conduct a replicable methodology that planners and

advocatescanusetoevaluatethreatstoaffordablehousingfromdevelopmentand

to identify opportunities for protecting affordable housing in their cities. As Dr.

Mueller’sgraduateresearchassistant,Iamhelpingtodesignarubricforcomparing,

acrossmanycriteria,“activitycorridors”indifferentpartsofthecity.Onecriterion

bywhichwewould liketocomparethecorridors is transitaccessto jobs for low‐

incomeresidentsofeachrespectivecorridor.Thistermprojectrepresentsmyeffort

to design a replicable geospatial analytical method for evaluating transit

connectivity fromaffordablehousing to jobs invariouspartsof the city.Although

theGreenandInclusiveCorridorsprojectcompareseightcorridorsinAustin,forthe

purposes of developing the methodology and presenting it in this paper, I have

narrowedthestudyareastothreecorridors.

ProjectObjective

Theobjectiveofthisprojectistodesignandconductareplicablegeospatial

analyticalmethodforcomparingdifferentneighborhoodsintermsofthenumberof

3

low‐paying jobs that are easily accessible by public transit from each

neighborhood.1

Datarequiredfortheanalysis

TheanalysisIhavedesignedrequiresthefollowingdata,regardlessofthecityto

whichtheanalysisisapplied.

Boundarydatafortherespectivestudyareastobecompared.

Locationdata for theaffordablehousingstock. If informationregarding the

number of units in affordable buildings is available, this can be used to

improvetheprecisionoftheanalysis.

Routedataforthepublictransitsystem.Ifheadwaydataisavailable,thiscan

beusedtoimprovetheprecisionoftheanalysis.

Locationdataforrelevantjobs.Asthisanalysisisconcernedwithaffordable

housing it is assumed that the housing residentswork low‐paying jobs, so

onlytheseareincludedintheanalysis.

MeetingthesedatarequirementsintheAustincontext

For this analysis in Austin, I met each of the data requirements in the

followingways.

1Forthepurposesofthisanalysis,wetook“accessibility”tomeanaccessiblewithouthavingtotransferbuses.InAusitn,transferringbetweenbuslinestendstorequirelongwaitingtimeswhichmakesitfarfromidealforcommuters.Althoughpeoplewithoutotheroptionsdocommutethisway,thisanalysisisdesignedtoproduceameasureofqualitysoweareonlyincludingtheone‐buscommutes.

4

Boundarydata for the respective studyareas tobecompared. As previously

noted, the larger project of which this geospatial analysis is a part is a corridor

project that looks at eight corridors in Austin. Dr. Mueller, my colleague Sara

McTarnaghan, and Idecided todrawour studyboundaries ashalf‐milebuffers to

eachsideofthecorridor.SaraMcTarnaghancreatedtheshapefilesweareusingin

thisproject according to this specification. In thispaper, I focuson threeof these

corridors: Burnet Road,Manor Road, and East Riverside Drive. Map 1 shows the

extentandlocationsofthesethreestudycorridors.

Map1:Thethreestudyareas

Manor Corridor

Burnet Corridor

Riverside Corridor

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Created by: Cliff Kaplan & Sara McTarnaghan | Fall 2014Data Sources: City of Austin GIS Data


5

Locationdatafortheaffordablehousingstock. The datawe use to track the

affordable housing stock in Austin comes from three separate sources, each for a

differenttypeofhousingstock.FromBBCConsulting,weobtainedaddressdataon

government‐subsidized multi‐family affordable housing, which we geocoded to

create a point feature‐class. This data included information about the quantity of

unitsateachbuilding.FromInvestorIncentives,arealestatedatafirm,weobtained

address information for Class Cmulti‐family buildings withmore than 50 units.2

Thisdataincludedinformationaboutthequantityofunitsatdifferentrentalvalues

andsizes,fromwhichwewereabletoselectforinclusionintheanalysisonlythose

buildingsthatmeetcurrentaffordabilitystandardssetbytheHousingAuthorityof

theCityofAustin.3Fordataonnon‐subsidizedbuildingsof less than50units,we

hadtocombineinformationfromtwosourcestocreateanestimate.FromtheTravis

CountyAppraisalDistrict (TCAD),weacquireddata that included theaddressand

numberofunitsforallClassCbuildingsinthecity,fromwhichweusedonlythose

withfewerthan50units.ThisTCADdatadidnotincluderentalvaluesandthusdid

not indicate which buildings were uniformly affordable, which were uniformly

unaffordable to low‐income residents, and which had both affordable and

unaffordableunitsandinwhatproportions.Asurvey(N=50)ofClassCbuildingsof

less than 50 units, conducted last summer by Housing Works, found that

2ClassCbuildings“aretypicallymorethan20yearsoldandlocatedinlessthandesirablelocations.Thepropertyisgenerallyinneedofrenovation,includingupdatingthebuildinginfrastructuretobringituptodate.Asaresult,ClassCbuildingstendtohavethelowestrentalratesinamarketwithotherClassAorClassBproperties”(FromRealtyMogul:https://www.realtymogul.com/blog/what‐does‐it‐mean‐when‐a‐property‐is‐class‐a‐class‐b‐or‐class‐c).3AsofApril1st,2014,theseaffordabilitystandardsare:Efficiency‐$696;1bedroom‐$853;2bedroom‐$1074;3bedroom‐$1454.

6

approximately 25% of units surveyed met affordability standards. Therefore, we

usedtheaddressdataobtainedfromTCADandmultipliedthenumber‐of‐unitsdata

thereinby0.25 toestimate thenumberand locationsofaffordableunits inmulti‐

family buildings of less than 50 units. All of the above data came in the form of

spreadsheets. We geocoded it ourselves to create point feature‐classes. For the

purpose ofmy analysis, itwas not necessary tomaintain the distinction between

thesethreetypesofaffordablehousingstock,soImergedthethreefeature‐classes

into one single shape file containing a point for every building in Austin with

affordable units. Map 2 shows the locations and sizes (number of units) of the

affordablehousingstockwithinthestudyareas.

Routedataforthepublictransitsystem.AlthoughAustinhasa rail lineused

bysomecommuters, thisanalysis focusesexclusivelyonthemuchmoreextensive

bus system. From CapMetro, we acquired a line feature class containing a line

feature foreachpublicbus line.Map3 shows the full extentof thebus system in

Austin,asitrelatestothelocationsofthestudyareas.

Location data for relevant jobs. From the U.S. Census Bureau website,

http://onthemap.ces.census.gov/, Iexportedapointshape file thathasapoint for

everycensusblockinAustin,withafieldthatcontainsthenumberofjobswithinthe

$15,000to$40,000annualpayrange. (Thedata is from2011).Map4showsthe

spatialdistributionofjobswithinthe$15,000to$40,000annualpayrange,asthey

relatetothelocationsofthestudyareas.

Of thedata required for this analysis, thehousing stockdatawas themost

complicatedtoacquireandthiswilllikelybethecaseanywherethisanalysisis

7

conducted.Transitroutedatatendstobeeasytoacquireincitiesthathavetransit

systems.ThejobsdataIusedisavailablefortheentireUnitedStates.

Map2:Thelocationsandsizesoftheaffordablehousingstockwithinthestudyareas

Manor Corridor

Burnet Corridor

Riverside Corridor


Created by: Cliff Kaplan | Fall 2014Data Sources: BBC Consulting; Investor Incentives;

Travis County Appraisal District; Housing WorksNAD 1983 StatePlane Texas Central FIPS 4203 (US Feet)¯ 0 1.5 30.75 Miles

Legend

Number of Units

Less than 50

51 - 100

101 - 200

More than 200

8

Map3:TheCapMetrobussysteminAustin,TX

Manor Corridor

Burnet Corridor

Riverside Corridor


Created by: Cliff Kaplan | Fall 2014Data Sources: CapMetro


Legend

CapMetro bus lines

9

Map4:Jobswithinthe$15,000to$40,000annualpayrange

Manor Corridor

Burnet Corridor

Riverside Corridor


Created by: Cliff Kaplan | Fall 2014Data Sources: http://.onthemap.ces.census.gov,

U.S. Census BureauNAD 1983 StatePlane Texas Central FIPS 4203 (US Feet)¯ 0 2 41 Miles

Legend

Jobs!( 20 - 300

!( 301 - 1000

!( 1001 - 5000

!( More than 5000

10

Outliningtheobjectivesoftheanalysis

To accurately describe and compare different corridors in terms of the

number of low‐paying jobs that are easily accessible by public transit from

affordablehousingwithineachcorridor,theanalysismustconsider:

Thebuslinesservingeachcorridor,

thenumberofjobstowhichthosebuslinesprovideaccess,

thefrequencywithwhichthebusespassthroughthecorridor,and

theportionofaffordableunitswithaccesstoeachbusline.

Conductingtheanalysis

The analysis that I have designed is conducted on one corridor at a time,

allowingtheanalysttocomparetheresultsamongthecorridorsattheend.

Forclarity,Iwilldescribethestep‐by‐stepprocessofanalysisfortheManor

corridor. In the Results section, Iwill provide the results of analysis for all three

corridors,alongwithillustrativemaps.

Step1:Identifythebuslinesthatservethestudyareaandcreateafeatureclass

ofonlythoselines.

Use Select by location to select from the bus lines layer those lines that

intersectthestudyarea.Then,useExportdatatocreateafeatureclassthatisonly

those linesthatservethestudyarea.UsetheAttributeTable for thisnewlayerto

examinethelinesandtheirrelevancetothisanalysis.InthecaseofAustin,thebus

data does not include information about hours of operation or the bus headways

(which correspond to the number of buses on the line at a given time.) For this

information,IusedbusschedulesfromtheCapMetrowebsiteandImanuallyadded

11

thisinformationtoafieldIcreatedintheAttributeTable,calledBus_at_RH(Buses

atrushhour).Ichosetoeliminatecertainbusesthatappearedtonotbeusefulfor

getting to and fromwork formost people. (For instance, I eliminated UT Shuttle

BuseswhichruntoandfromtheUniversityofTexascampusandareoperatedby

CapMetrofortheexclusiveuseoftheuniversitycommunity.)

Afterdeletingthebuslinesthatarenotrelevanttothisstudy,thereremain

sixlinesthatservetheManorcorridor,showninMap5.

Figure1:TheAttributeTablecontainingthesixbuslinesthatservetheManorCorridorthatI included inthisstudy,withtheaddedfieldforthenumberofbusesthatpassduringrushhour.

Step2:Count the totalnumber of jobs (in the relevantpaybracket) thatare

accessibleonthesebuslines.

UseSelectbylocationtoselectfromthejobslayerthosejobs(pointfeatures)

that are within 0.5 miles of the newly created bus line layer.4Use the Statistics

dialoguebox,accessiblethroughthejobslayerAttributeTabletosumthequantity

ofhighlightedjobs.Makeanoteofthisnumber;itwillbeusedlaterintheanalysis.

Map6showsthejobsthatareaccessiblebybusfromtheManorcorridor.Itisnot

40.5milesisaconventionalestimateforthedistancethatpeoplewillgenerallybewillingtowalktoorfrompublictransportonadailybasis.

12

Map5:ThebusesthatservetheManorcorridor


Created by: Cliff Kaplan | Fall 2014Data Sources: CapMatro

NAD 1983 StatePlane Texas Central FIPS 4203 (US Feet)¯ 0 2 41 Miles

Legend

Bus lines serving Manor

Manor Corridor

13

necessarytocreateashapefilecontainingonlythesejobs;theanalysiscanbedone

leaving the original jobs shape file intact. I have exported the highlighted jobs to

create a “Jobs fromManor” point feature class for the purposes ofMap 6, which

showsthejobsaccessiblebytransitfromtheManorcorridor,alongwiththetransit

lines.

Map6:Thelow‐payingjobsaccessiblebytransitfromtheManorcorridor

FromtheManorcorridor,thereare97,151low‐payingjobsaccessiblebybus.

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Created by: Cliff Kaplan | Fall 2014Data Sources: CapMatro; U.S. Census Bereau


Legend

Jobs!( 20 - 300

!( 301 - 1000

!( 1001 - 5000

!( More than 5000

Bus lines serving Manor

Manor Corridor

14

Steps3,4,5,arerepeatedsequentially foreachbus line thatserves thestudy

area:

Step3:CountthenumberofjobsaccessiblebybuslineX.

UseSelectbyLocationtoselectthejobswithin0.5milesofbuslineX.Usethe

StatisticsdialogueboxintheAttributeTabletosumthequantityofhighlightedjobs,

andmake a note of this number. In theAttribute Table for the buses serving the

studyarea,createafieldcalledJobsandpopulateitwiththenumberofjobswithin

thereachofeachbusline.Map7(asanexample)showsbusline#18alongwiththe

49,808jobswithin0.5milesofthebusline.Map8(asanotherexample)showsbus

line#350alongwiththe12,412jobswithin0.5milesofthatbusline.

Figure2:Thesameattributetable,nowwiththeadded“Jobs”field.

Step4:Multiplythenumberofbusesatrushhourbythenumberofjobsonthe

buslinetocreateacomposite“Usefulness”score.

The number of jobs on the bus line and the frequency of buses are both

factorsinthe“usefulness”ofthatbuslineforcommuting.AddafieldintheAttribute

TableandusetheFieldCalculator topopulatethe field,multiplyingthenumberof

busesatrushhourbythenumberofjobsreachedbythebusline.

15

Map7:Jobsaccessiblefromthebusline#18

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NAD 1983 StatePlane Texas Central FIPS 4203 (US Feet)¯ 0 1 20.5 Miles

Legend

Jobs!( 20 - 300

!( 301 - 1000

!( 1001 - 5000

!( More than 5000

Route_18

Manor Corridor

16

Map8:Jobsaccessiblefromthebusline#350

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Legend

Jobs!( 20 - 300

!( 301 - 1000

!( 1001 - 5000

!( More than 5000

Bus line #350

Manor Corridor

17

Figure3:The sameattribute table,nowwith theadded “B_x_J” (Busx Jobs)field,whichisanexpressionof“Usefulness”forcommuters.

Step5:Weighteachbus line’sUsefulnessscoreaccording to theportionof the

studyarea’saffordablehousingstockthatthebuslineserves.

Ourinterestisincomparingcorridorsbytheaccessibilitytojobsprovidedto

thembypublic transit.Therefore, the “Usefulness” scoresofbus lines thatdonot

servetheentirecorridor(whichismostbuslines)mustbeweightedaccordingly.As

showninMap9,forinstance,busline#18(shownwitha0.5milebufferaroundit)

only serves a portion of the affordable housing stock in the Manor corridor. To

calculatethisportion,useSelectbyLocationtoselectthehousingthatintersectsthe

studyarea.UsetheStatisticsdialogueboxintheAttributeTabletosumthenumber

ofaffordableunitsinthestudyarea.Thiswillbethedenominatorintheproportion.

For the Manor corridor, this number is 1373.5. (Recall that the housing data

includesanestimatethat25%ofallunitsinsmallClassCbuildingsareaffordable.

This explains the possibility of fractions of units in the data.) Now use Selectby

Location to select the housing within 0.5 miles of the bus line. Use the Statistics

dialogue box to sum the quantity of selected housing units. This number is the

numerator. In the case of bus line #18 passing through the Manor corridor, this

numberis373.5.Dividethenumeratorbythedenominatorandentertheresultinto

18

Map9:The#18buslineservesonlyaportionoftheManorCorridor

IH 3

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MARTIN LUTHER KINGFM 969



NAD 1983 StatePlane Texas Central FIPS 4203 (US Feet)¯ 0 0.8 1.60.4 Miles

Legend

Units

Less than 50

51 - 100

101 - 200

More than 200

Jobs!( 20 - 300

!( 301 - 1000

!( 1001 - 5000

!( More than 5000

Bus line #18

0.5 mile buffer around bus line #18

Manor Corridor

19

Map 10: The #350 bus line serves only a portion of the Manor Corridor

IH 3

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MARTIN LUTHER KINGFM 969

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NAD 1983 StatePlane Texas Central FIPS 4203 (US Feet)¯ 0 0.8 1.60.4 Miles

Legend

Units

Less than 50

51 - 100

101 - 200

More than 200

Jobs!( 20 - 300

!( 301 - 1000

!( 1001 - 5000

!( More than 5000

Bus line #350

0.5 mile buffer around bus line #350

Manor Corridor

20

anewfieldintheattributetable;thisistheproportionbewhichwewillweighthe

“Usefulness” scores. Bus line #18 is useful to 373.5 / 1373.5 = 0.27, or

approximately 27% of the affordable housing in the corridor. Map 10 shows the

portionoftheManorcorridorthatisservedbybusline#350.

Figure 4: The same attribute table, now with the added Pn_of_Uts field(“Portion of Units Served”), which will serve as the weights for the“Usefulness”ofeachbusline.

RepeatSteps3,4,and5untiltheBusesatRushHour,Jobs,B_x_J(Usefulness),

and Pn_of_Unts (theweights) fields have been populated for all of the bus

lines.

Step6:Weighandsumthe“Usefulness”scores

AddanewfieldtotheAttributeTableandusetheFieldCalculatortomultiply

the“Usefulness”scorebytheassociatedweight(representingtheportionofunitsin

thecorridor that isable to takeadvantageof theusefulnessof thatparticularbus

line).

Figure5:Thesameattributetable,nowwiththeadded“WeightedUsefulness”field.

Sum these weighted scores. In the case of the Manor corridor, the sum is

587,336.93.

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Step 7:Multiply the study area’s Usefulness score sum by the portion of all

transit‐accessiblejobsthataretransit‐accessiblefromthestudyarea.

WhenweaddedtogethertheweightedUsefulnessscoreforeachbusline,we

necessarilydoublecountedanyjobsthatareservedbymorethanonebusline(or

triplecountedthem,etc.).Wecanimagineacorridorthathastransitaccesstoalow

numberof jobs, but forwhich there aremanybuses that come frequently to take

commuterstothosejobs.Iftherearemanymoreworkerslivinginthecorridorthan

there are jobs that are accessible from the corridor, it is not as good as having

enough jobs for all theworkers.We account for this bymultiplying the summed

Usefulnessscoreforthestudyarea(587,336.93inthecaseofManor)bytheportion

of all transit‐accessible jobs thatare transit‐accessible from the studyarea.Aswe

calculatedearlier,thereare97,151jobsthataretransit‐accessiblefromtheManor

corridor.Thereare198,082jobsaccessiblebytransitcitywide,whichiscalculated

byusingSelectbyLocationtoselectallofthejobswithin0.5milesoftheentirebus

systemandusingStatisticsintheAttributeTabletosumthenumberofjobsinthe

relevantpayrange.Therefore,thefinalscorefortheManorcorridoris587,336.93x

[97,151/198,082]=288,064.39.

Thisscoreisacompositeofthenumberofaccessiblejobsfromeachbusline

multipliedby thenumberofbusesrunningon the line,weighted for theextent to

which the lineserves theaffordableunits in thecorridor,and the totalnumberof

jobs accessible by transit from the corridor. Therefore, the final score is best

understoodasanindexusefulforcomparingcorridorstooneanother,butwithout

aneasilygraspablemeaninginitsownright.

22

Results

I conducted the analysis described above on the Manor, Burnet, and

Riversidecorridors.Thefollowingtablesshowtheresultingnumbers.

Figure6:CalculationofresultsfortheManorcorridor

Figure7:CalculationofresultsfortheBurnetcorridor

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Figure8:CalculationofresultsfortheRiversidecorridor

Figure9:Asummaryofthefinalscores

Corridor Final Score Actual number of accessible jobs

Manor 288,064.39

97,151

Burnet 1,195,604.92

198,082

Riverside 542,322.67

104,864

Analysis

According to this geospatial analytical method, affordable housing in the

Burnetcorridorhasslightlymorethantwotimesasmuchaccessibilityviatransitto

low‐payingjobsinAustinasdoesaffordablehousingintheRiversidecorridor,and

slightlymorethanfourtimesasmuchasthatintheManorcorridor.Thatresultis

mademoreinterestingbytheobservationthatthoserelationshipsarenotmirrored

24

bytheactualnumberofjobsaccessiblebytransitfromeachcorridor.Forinstance,

the Manor corridor’s final accessibility score is only 47% less than that of the

Riverside corridor.However, the actual numberof jobs accessibleby transit from

Manorisonly7%lessthanthenumberofjobsaccessiblebytransitfromRiverside.

Thedisparitybetweenthefinalaccessibilityscoresforthesetwocorridorsis

largelyexplainedbythefactthattheRiversidecorridorhasmuchhighervolumesof

bus traffic. 30 buses typically pass through theManor corridor during rush hour,

while54typicallypassthroughtheRiversidecorridor,accordingtoCapMetrobus

schedules.Thisdisparityisexacerbatedbythefactthat,onaverage,busespassing

throughtheManorcorridoronlyrunwithinaneasywalk(0.5miles)of46%ofthe

affordableunitsinthecorridor,whilethatfigureis57%intheRiversidecorridor.

But what accounts for the Burnet corridor’s score being twice that of the

Riverside corridor? Typically, 39 buses pass through the Burnet corridor during

rush hour, 20% fewer than pass through the Riverside corridor. Nor is coverage

remarkably better in the Burnet corridor than it is in the Riverside corridor; the

average bus passing through the Burnet corridor is accessible to 60% of the

affordableunitstherein,comparedto57%intheRiversidecorridor.

ThedifferenceinaccessibilitybetweentheBurnetcorridorandtheRiverside

corridorappearstobeexplainedbywherethebusesgo.Theaveragenumberofjobs

accessiblefromabusthatpassesthroughtheBurnetcorridoris50,145whereasthe

average number of jobs accessible from a bus that passes through the Riverside

corridoris31,678,37%fewer.The“Usefulness”scoresfortheaveragebuslinesthat

25

pass through the Burnet and Riverside corridors respectively are 265,860 and

184,266;Riverside’sscoreis31%lowerthanBurnet’s.

According to these observations, it appears that Manor’s low accessibility

score is caused by infrequent buses and a selection of buses that travels to a

relatively low number of jobs (97,151), while Burnet’s high accessibility score is

causedbythefactthateachbusservingtheBurnetcorridortendstotraveltomany

more jobs thando thebuses serving theother corridors, and together theBurnet

buses reach many more jobs (144,894) than do the buses serving the other

corridors.Maps11a,11b,and11cshowtheaffordablehousingstockineachstudy

corridor,asitrelatestobuslinesofvarying“Usefulness.”

Futureworkandconclusion

Continueddevelopmentofthisanalyticalmethodiswarranted.Conceptually,

manyofthemeasuresusedtocomparethecorridorstooneanother(“Usefulness,”

for example) are not as clear as they might be, in part due to their composite

natures.Itwillbeworthwhiletofindwaysofcombiningthedatathatcapturesthe

variation but is more intuitive to interpret. Technically, this method is time

consuming; its iterative nature (repeating several steps for each bus line in each

corridor) ought to make it automatable using Model Builder. I will likely pursue

bothconceptualandtechnicalstreamlines,asIcontinuetousethismethodforthe

Greenand InclusiveCorridorsproject.Thus far, the analysis shows that thereare

severalfactorsthatcancauseacorridor’shousingstocktohavemoreorlesstransit

access to job opportunities, and that these factors affect different corridors in

different ways. Planners seeking to preserve affordable housing with high

26

accessibilitytowork,orthoseseekingtoimproveaccessibilitywhereitis low,can

usethisanalyticalmethodtodiagnoseproblemsandstrategizeforsolutions.

Maps11a,11b,and11c:Theaffordablehousingstockineachstudycorridor,asitrelatestobuslinesofvarying“Usefulness.”Thethicknessofthebuslineindicatesthenumberofjobsthatareaccessiblefromthatline.Map11a:Manor Map11b:Burnet

Map11c:Riverside

27

ListofMaps

Map1:Thethreestudyareas–Page4

Map2:Thelocationsandsizesoftheaffordablehousingstock–Page7Map3:TheCapMetrobussysteminAustin,TX–Page8Map4:Jobswithinthe$15,000to$40,000annualpayrange–Page9Map5:ThebusesthatservetheManorcorridor–Page12Map6:JobsaccessiblebytransitfromtheManorcorridor–Page13Map7:Jobsaccessiblefromthebusline#18–Page15

Map8:Jobsaccessiblefromthebusline#350–Page16

Map9:The#18buslineservesaportionoftheManorCorridor–Page18Map10:The#350buslineservesaportionoftheManorCorridor–Page19Maps11a,11b,and11c:Theaffordablehousingstockineachstudycorridor,

asitrelatestobuslinesofvarying“Usefulness.”–Page26

28

DataAffordableHousingInventory[spreadsheet].(2014).BBCConsulting:Austin,TX.

AffordableHousingSurvey[spreadsheet].(2014).HousingWorks:Austin,TX.

CapitalMetro Bus Routes [shapefile]. (2012). CapMetro data and statistics portal.

Available:https://www.capmetro.org/datastats.aspx?id=129

Jobsthatpaybetween$15,000and$40,000annually[shapefile].(2011).U.S.Census

Bureau online interface, On the Map. Available:

http://onthemap.ces.census.gov/

Large Class C properties in Austin, TX [spreadsheet]. (2014). Investor Incentives:

Austin,TX.

ClassCmulti‐familyparcels[spreadsheet].(2014).TravisCountyAppraisalBoard:

Austin,TX.

Documents

¯ NAD 1983 StatePlane Texas Central FIPS 4203 (US Feet) · PDF file¯ 01.5 30.75 Miles NAD 1983 StatePlane Texas Central FIPS 4203 (US Feet) Legend Number of Units Less than 50 51