BBC HorizonThe Age of Big Data.docx

BBC HorizonThe Age of Big Data.docx

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BBCHorizonTheAgeofBigData

BBCHorizon:

TheAgeofBigData

InLosAngeles,aremarkableexperimentisunderway.

Facethewall,facethewallbeforeIputyouinhandcuffs.

Thepolicearetryingtopredictcrimebeforeitevenhappens.

Itactuallygivesusaforecastaboutwherecrimeismostlikelytohappeninthenext12hours.

IntheCityofLondon,thisscientist-turned-traderbelieveshe'sfoundthesecretofmakingmillions,withmaths.

Thepotentialtodothingswithdataisfantastic,fantastic.

AndinSouthAfrica,thisstar-gazerhassetouttocataloguetheentirecosmos,bylisteningtoeverysinglestar.

Whatunitesthesedifferentworldsisanexplosionindata.Thevolumeofit,thedynamicnatureofthedataischanginghowweliveourlives.

Injustthelastfewyears,we'veproducedmoredatathaninallofhumanhistory.

Inthisfilm,wefollowthepeoplewhoareminingthisdata.

It'ssettobecomeoneofthegreatestsourcesofpowerinthe21stcentury.

6am,LosAngeles.ThestartofshiftintheFoothilldivision.

OfficerSteveNunes,a12-year-veteranoftheLAPD,andhispartnerDannyFraserheadouttopatrol.

Rightnow,we'renorthofLosAngeles,downtownLosAngeles,intheSanFernandoValleyarea.

TheirbeatisoneofLA'stoughestneighbourhoods.

There'salotofBFMVs,burglaryfrommotorvehicles.

There'salotofrobberies,there'salotofgangandnarcoticactivityoverhere.

There'salotofpeoplesellingdrugs.

Thegangthat'sinthisareaarecalledtheProjectBoys.

They'reaHispanicgang.

Despitetheirexperienceandintimateknowledgeoftheneighbourhood,today,theirpatrolisbeingcontrolledbyacomputeralgorithm.

Youknow,Iwasn'treallytoohappyaboutit,youknow,speciallyasapoliceofficeryouknow,wekindofgooffofwhatweknowfromourtraining.

Weweren'ttoohappyaboutacomputertellinguswhereweneedtodoourpoliceworkandwhatareaweneedtodrivearound.

SteveandDannyarepartofaground-breakingtrial.

Anequationisbeingusedtopredictwherecrimewilloccurontheirwatch.

Isawsomepeoplehangingoutbythelaundry,likethelittlelaundry.

Icanseethecorner.

Allright,let'sstop.

Ifitspredictionsarecorrect,thesystemwillberolledoutacrossallLA.

-Hey,stop,yeah,stop.-Stop.

Putyourhandsonyourhead.

AndthecomputeralgorithmwillbecomearoutinepartofSteve'sworkinglife.

Spreadyourfeet,faceforward.

-Haveanythingonyou?

-Stopmoving.

Facethewall,facethewallbeforeIputyouinhandcuffs.

YouaProjectBoytooorno?

TheambitiontopredictcrimewasbornoutofaremarkablecollaborationbetweentheLAPD...

andtheUniversityofCalifornia.

JeffBrantinghammightseemanunlikelycrimefighter.

Aprofessorofanthropology,heisanexpertonremotehunter-gatherertribesinChina,buthe'sconvinced

thatfromremoteChinatoganglandLA,allhumanbehaviourisfarmorepredictable

thanyoumightliketobelieve.

Weallliketothinkthatweareincontrolofeverything,butinfactallofourbehaviourisveryregular,verypatternedinwaysthatisoftenfrighteningtous.

Offendersarenodifferent.

Theydoexactlythesamethingsoverandoverandoveragain,andtheircriminaloffendingpatternsemergerightoutofthatregularityoftheirbehaviour.

JeffbelievedhecouldfindrepeatingpatternsofcriminalbehaviourintheLAPD'svastdataset-

13millioncrimesrecordedover80years.

TheLAPDhavedrovesanddrovesofdataaboutwhereandwhencrimeshavebeenoccurring.

Itrepresentsatreasuretroveofpotentialinformationforunderstandingthenatureofcrime.

TheLAPDalreadyusetheircrimedatatoidentifyhotspotsofcrime,butthatonlytellsthemwherecrimehasalreadystruck.

We'vegottenverygoodatlookingatdotsonamap,andwhere,wherecrimehasoccurredandtheproblemwiththatisthat,sometimes,you'remakinganassumptionthattodayisthesameasyesterday.

JeffBrantinghamplannedtodosomethingmoreradicalandmoreusefulpredictthefuture.

Hebelievedhecouldusepatternsinthecrimedatatopredictwhereandwhencrimewaslikelytooccur.

We'velongusedthepatternsinnaturetomakepredictions.

Fromthesettingsun,

welearnedwhentoexpectthenewday.

Thephasesofthemoonallowedustoforecasttheebbandflowofthetides.

Andfromobservingthepatternsofthestars,wemasteredtheartofnavigation.

ButJeffBrantinghamwantedtodosomethingfarmoreambitious.

Hewantedtoteaseoutpatternsintheapparentchaosofhumanbehaviour,touncoverthemintheLAPD'svastdatasetof13millionpastcrimes.

Youcanhavegutfeelingsaboutthecrime,butultimately,youneedtothinkaboutworkinginamathematicalframework.

Becausemathematicsgivesyoutheabilitytounderstandexactlywhythingsarehappeningwithinthedatainawaythatgutfeelingsdonot.

Jeffneededanexpertinpatterndetection.

Heturnedtohiscolleague,UCLAmathematicianGeorgeMohler.

Asmathematicians,we'reinterestedinunderstandingwhat'saroundyouso,youknow,howdowavespropagateifyouthrowapebbleintothewater?

Thedistributionoftreesinaforest.

Somathematicalmodels

canhelpyouunderstandthosetypesofthings.

Georgecouldusemathematicaltoolstoseewhatwashiddeninthecrimedata.

Andtherewerehintsofapatterninit.

Whatyouseeisthatafteracrimeoccurs,there'sanelevatedriskandthatrisktravelstoneighbouringregions.

Sowhatwewantedtodoisdevelopamodeltotakethatintoaccountsopolicecouldmaybeusethatinformationtopreventthosecrimesfromoccurring.

Hestartedwithamathematicalmodelthatwasalreadybeingused,righthereonthewestcoastofAmerica.

SouthernCaliforniaisearthquakecountry.

SittingontheSanAndreasFault,there'sanaverageof10,000earthquakesandafter-shockseveryyear.

Thebiggestfor100yearswastheLomaPrietaearthquakeof1989.

Itsepicentrewashere,justoutsideSantaCruz,California.

Thereisquitesimplynomathematicalmodelthatcanpredictanearthquakelikethisone.

Butaftertheearthquakecometheafter-shocksandthat'sadifferentmatter.

Sowe'reseveralhundredmetresfromtheepicentre.

Nearbywasoneoftheafter-shocksoftheoriginalLomaPrietaearthquake.

Afteralargeearthquakeoccurs,thereisaprobabilitythatanotherearthquakewillfollownearbyinspaceandtime.

Georgediscoveredseismologistshadfoundapatterntoearthquakeafter-shocksanddevelopedanalgorithmtopredicttheseafter-shockclusters.

Thesetypesofclusteringpatternsarealsoseenincrimedata.

So,afteracrimeoccurs,youwillseeanincreasedlikelihoodoffutureeventsnearbyinspaceandtime.

Youcanthinkofthemasafter-shocksofcrime.

GeorgeandJefftooktheequationforpredictingearthquakeafter-shocksandbegantoadaptittopredictcrime.

Sothemodelisbrokenintoseveralparts,sotheoverallrateofcrime,whichwe'llcallLamda,modelstherateofeventsinspaceandtime.

WeusetheGreekletterMyutorepresentthebackgroundamountofcrimethat'sgoingon.

ThesecondcomponenttoLamdaisG.

Gmodelsthedistributionofcrimesfollowinganinitialevent.

Thiswholetermoveralldescribeswhatwecallself-excitation,thatacrimethatoccurstodayactuallyself-excitesthepossibilityoffuturecrimes.

SoLamdaequalsMyuplusG,isthatright?

Well,sortof,soLamdaequalsMyuplusGpositionedatallthepasteventsinyourdataset.

GeorgeandJefftooktheiralgorithmbacktothestreetsofLA.

Whentheypluggedtheoldcrimedataintotheequation,itgeneratedpredictionsthatfittedwhathadhappenedinthepast.

Butcoulditalsopredictthefuture?

Theybegantoproducedailycrimeforecasts,identifyinghotspotswherecrimewaslikelytostrikeinthefuture.

-Adam11,Nunes.-Sir

-Thern.-Sir.

-Adam23,Fowler.-Sir.

-Wallier.-Sir.

Let'sgotothemissionmapsifyouwould,please.

Today,theLAPDisputtingthesepredictionstothetest.

ThecopsinFoothillareassignedboxesofjust500squarefeetwherethealgorithmpredictscrimeismostlikelytooccurintheir12-hourwatch.

Right,predictivemissionfortodayis,we'vegot15boxesheretoaddress,inAdam11'sarea,12260FoothillBoulevard.

They'reinstructedtohittheirboxesasoftenastheycan.

OsborneandFoothillBoulevard.

Soyou'vegotyourmissionfortheday?

Solet'sgooutthere,havefunandbesafe.

Yeah,thereisahomicideblinkingupthere.

ThetrialismonitoredattheRealTimeCrimeCentreindowntownLA.

Whatwe'relookingathereistheforecastthatwasproducedbythePredPolsoftware.

Soifyouseeonthecentreofthismap,we'vegotthreenearlycontiguousforecastboxesaroundthisarea,andthenanadjacentone.

Sothisisgoodinformationfortheofficers.

Theycangooutthere,workupanddownthatstreet,Sheldon,andsomeofthosesidestreets,andlookforcriminalactivityorevidencethatcriminalactivitymightbeafoot.

OK,Roger,we'lltakeit.

SteveandDannyhavegotthewordtogo.

Themodelhaspredictedcarcrimeinaboxontheirbeat.

Youknowwhatthecallisright?

Thefiveincidentsweremacerated.

Lookslikeit'sakid.

Yeah,it'sthesameaddressasthatkidthatwehadyesterday.

Suspectsfour,male...Whentheyreachtheirassignedhotspot,theyfindacold-platedcar.

Thelicenceplatesdon'tmatchthevehicle.

They'regettingwhattheyneed,huh?

Whentheycallthenumberin,itturnsoutthecar'sbeenstolen.

Itwasanareawherethere'salotofGTAs,whichis"Grandtheftauto",peoplewerestealingcars.

Rightoutofrollcall,rightwhenwegotdownoneoftheboxestheywentinto,oneoftheareastheystartedpatrolling,rightawaytheyranacaranditcamebackstolen.

InFoothill,theyfoundusi