3.4 Ndianiko kubvunza

Izera re digital rinoita kuti zvigadziriswe sampling mukuita zvakanyanya uye iri kuumba mikana mitsva yekusagadzirisa sampuli.

Mune nhoroondo yekuenzanisa, pane nzira mbiri dzakakwikwidzana: zvichida sampling nzira uye zvisiri-zvingave zvidzidzo nzira. Kunyange zvazvo nzira mbiri idzi dzaishandiswa mumazuva okutanga ekuenzanisa, zvichida shanduro yakauya kuzotonga, uye vazhinji vanoongorora zvekugarara vanodzidziswa kuona sevasingakwanisi sampling nekutya kukuru. Zvisinei, sezvandicharevera pasi apa, shanduko dzakagadzirwa nezera rejedi dzinoreva kuti ndiyo nguva yevanotsvakurudza kuti vaongororore zvisingabviri kutorwa. Kunyanya, zvichida sampling yave ichiita zvakaoma kuzviita mukuita, uye kusingakwanisi kutora sampuli kwave kuchikurumidza, inodhura, uye iri nani. Kutsvaga nokukurumidza uye kunotsvaga hakusi kungopera mukati mavo pachavo: vanoita kuti mikana mitsva yakawanda yakawanda seongororo dzakawanda uye mazamu makuru ekuenzanisa. Semuenzaniso, kuburikidza nekushandisa nzira dzisingasviki dzeCoperative Congressional Election Study (CCES) inokwanisa kuva neanenge kazhinji pane vatori vechikamu kupfuura zvidzidzo zvepakutanga vachishandisa shanduro yekuda. Chiyeuchidzo chikuru ichi chinoita kuti vatsvakurudzi vezvematongerwe enyika vadzidze kusiyana kwemaonero nemaitiro mukati memasangano nepamamiriro ezvinhu evanhu. Uyezve, zvose izvi zvakawedzerwa zviyero zvakasvika pasina kuderera muhutano hwekufungidzirwa (Ansolabehere and Rivers 2013) .

Parizvino, iyo inonyanya kushandisa nzira yekutsvaga tsvakurudzo yezvemagariro evanhu inogona kuenzaniswa . Pangangodaro sampling, nhengo dzose dzevanhu vanotarisirwa dzinenge dzichizivikanwa, dzisingabatsiri dzekutsvaga, uye vanhu vese vakagadziriswa vanopindura kuongororo. Kana izvi zvikaitika, hutano hwemasvomhu hunoita kuti hurumende dzive nehutano hwekutsvaga kwemuongorori wekushandisa samuenzaniso kuti ataure pamusoro pezvinangwa zvevanhu.

Munyika chaiye, zvakadaro, mamiriro ezvinhu ari pasi apa emigumisiro yemasvomhu haasati awanikwa. Semuenzaniso, pane kazhinji kacho kukanganisa nekukanganisa uye kwete. Nemhaka yezvinetso izvi, vanotsvakurudza kazhinji vanofanira kushandiswa zvakasiyana-siyana zvigadzirisho zvekuverenga kuitira kuti vaite zvinyorwa kubva pane zvavanoshandiswa kune vavanenge varo. Nokudaro, zvakakosha kusiyanisa pakati pezvinogona kuenzanisirwa munyanzvi , iyo ine simba yezvinyorwa zvevhangeri, uye zvichida sampling muitiro , izvo zvisingabvumirisi zvakadaro uye zvichienderana nemhando dzakasiyana-siyana dzokugadzirisa.

Nokufamba kwemazuva, kusiyana pakati pezvingaitwa sampling munyanzvi uye zvichida sampling muitiro zvave zvichiwedzera. Semuenzaniso, kusaremekedza kwave kuchiwedzera kuwedzera, kunyange mukukwirira, kuongorora kukuru (mufananidzo 3.5) (National Research Council 2013; BD Meyer, Mok, and Sullivan 2015) . Nhamba dzisingabatsiri dzakawanda kwazvo mune zvekutengesa foni zvenguva-dzimwe nguva kunyange dzakapfuura 90% (Kohut et al. 2012) . Izvi zvinowedzera musingaremekedzi zvinokanganisa huwandu hwekufungidzirwa nokuti kuongororwa kunowedzera kunowedzera kuenzanisa mifananidzo iyo vatsvakurudzi vanoshandisa kugadzirisa kusava nehanya. Uyezve, izvi zvinoderera muhutano zvakaitika kunyange pasinei nekuwedzera kwechikwereti kuburikidza neongororo vatsvakurudzi kuti varambe vakagadzirisa matanho. Vamwe vanhu vanovhunduka kuti idzi maitiro maviri ekuderera kwehutano uye mari inowedzera inoparadza nheyo yeongororo yekuongorora (National Research Council 2013) .

Mufananidzo 3.5: Nonresponse yakaramba ichingowedzera, kunyange mukutsvakurudza kwakakosha (National Research Council 2013; BD Meyer, Mok, and Sullivan 2015) . Nhamba dzisingabatsiri dzakakwirira kwazvo kumatarefoni ekutengeserana, dzimwe nguva kunyange dzakakwirira se 90% (Kohut et al. 2012) . Izvi zvinogara kwenguva refu musingarevi zvinoreva kuti kuunganidza deta kunodhura uye kuenzanisa hakuna kuderera. Yakagadzirirwa kubva kuna BD Meyer, Mok, and Sullivan (2015) , mufananidzo 1.

Panguva imwe chete iyo yave iri kuwedzera matambudziko ezvimwe nzira dzokuenzanisa, pane zvakare kwakave nekufadza kunofadza mune zvisingabviri zvidzidzo nzira . Kune nzira dzakasiyana-siyana dzekusava nemuenzaniso sampling nzira, asi chinhu chimwe chavanoita zvakafanana ndechokuti havagone kuwirirana mumatematic framework yekufungidzira sampling (Baker et al. 2013) . Mune mamwe mazwi, mune zvisingabviri sampling nzira dzose dzese hadzizivikanwe uye dzisiri dzekubatanidzwa. Nzira dzisingakwanisi nzira dzekuenzanisa dzine mbiri inotyisa pakati pevanhu vanotsvakurudza uye vanobatanidzwa nezvimwe zvinokanganisa zvinoshamisa zvevatsvakurudzi veongororo, zvakadai seLittary Digest fiasco (yakambotaurwa kare) uye "Dewey Vanotsvaga Truman," kuporofita kusina kururama pamusoro peU.S. presidential election of 1948 (chirevo 3.6).

Mufananidzo 3.6: Mutungamiri Harry Truman akabata musoro wepepanhau rakange risina kuzivisa kukunda kwake. Uyu musoro waive wakabatanidzwa muchikamu chekufungidzira kubva kune zvisingabviri zvidzidzo (Mosteller 1949; Bean 1950; Freedman, Pisani, and Purves 2007) . Kunyange zvazvo "Dewey Vanoparadza Truman" yakaitika muna 1948, ichiri chimwe chechikonzero chokuti vamwe vatsvakurudzi havana chokwadi pamusoro pekufungidzira kubva kune zvisingabviri zvidzidzo. Mhedziso: Harry S. Truman Library & Museum .

Chimwe chimiro chekusava nemuenzaniso sampling iyo inonyanya kukodzera kuzera rechidijisiti iko kushandiswa kwepanamani panels . Vatsvakurudzi vachishandisa mapurisa ari paIndaneti vanotarisa pane imwe nzvimbo inopa mupiki-kazhinji kambani, hurumende, kana yunivhesiti-kuvaka boka guru, rakasiyana-siyana rinobvumirana kushanda sevapinduri veongororo. Aya mapato emapato anowanzotorwa achishandiswa nenzira dzakasiyana-siyana dzakadai semakambani ekutsvaga mabhizinesi. Zvadaro, mumwe mutsvakurudzi anogona kubhadhara mupepaniti mupiro wekuwana samuenzaniso wevakabvunzwa nemafungiro aidiwa (semuenzaniso, kuratidza munyika yose vanhu vakuru). Aya mapurisa ari paIndaneti haasi mikana nokuti haisi munhu wose anozivikanwa, asiriyo zvingave zvekubatanidzwa. Kunyange zvazvo zvisingabviri pamakambani emakambani ari kutoshandiswa nevashambadzi vemagariro evanhu (semuenzaniso, CCES), pane imwezve nharo pamusoro pehuwandu hwenhamba dzinobva kwavari (Callegaro et al. 2014) .

Pasinei nekukakavadzana uku, ndinofunga pane zvikonzero zviviri nei nguva yakakodzera kuti vatsvakurudzi vezvemagariro evanhu vafunge nezvekusava nemuenzaniso. Chokutanga, mumakore ekudhindwa, kwakave nezvakawanda zvakagadzirwa mukuunganidza uye kuongororwa kwezvisiri izvo zvingaitwa. Aya maitiro matsva akasiyana zvakakwana kubva munzira dzakakonzera matambudziko munguva yakapfuura kuti ndinofunga kuti zvine musoro kufunga nezvavo se "kusingakwanisi kuenzanisa sampuli 2.0." Chikonzero chechipiri nei vatsvakurudzi vanofanira kufungisisa zvisingabviri kutaridzirwa ndezvokuti zvichida sampling in tsika inowedzera kuoma. Apo pane mazinga akakwirira easingaiti-sezvakunoita muongorori chaiyo ikozvino-zvirevo chaiwo zvekubatanidzwa kune vapindura hazvizivikanwe, uye naizvozvo, zvichida sampuli uye zvisingabviri zvidzidzo hazvisi zvakasiyana nevakawanda vanotsvakurudza vanotenda.

Sezvandambotaura kare, zvisiri zvisingabviri zvidzidzo zvinotariswa nekutya kukuru kwevanowanzoongorora nezvekugarisa, mune chimwe chikamu nekuda kwezvavanoita mune zvimwe zvikanganiso zvinonyadzisa mumazuva ekutanga ekutsvakurudza kwekuongorora. Muenzaniso wakajeka wekuti takasvika kusvika papi zvisingasviki zvinyorwa ndekutsvakurudza kwakaitwa naWei Wang, David Rothschild, Sharad Goel, naAndire Andrew Gelman (2015) iyo yakanyatsogadzirisa migumisiro yemusarudzo we 2012 weUnited States uchishandisa sarudzo isingaiti American Xbox vashandisi-chimiro chakanga chisingaregi chechiAmerican. Vatsvakurudzi vakabvunzurudza vanhu vakapindura kubva muChina yekutamba, uye sezvamungatarisira, Xbox skewed skewed varume nevanokanganisa: vane makore 18 kusvika ku29 vanoita 19% evasororate asi 65% yeXbox samples, uye varume inoumba 47% ye electorate asi 93% yeXbox samuenzaniso (chirevo 3.7). Nemhaka yeiyi yakawanda yevanhu vanoona nezvekuwanda kwevanhu, iyo data yakashata ye Xbox yakanga iri chiratidzo chisina kunaka chekudzoka kwesarudzo. Iyo yakafanotaura kukunda kwakasimba kwaMitt Romney pamusoro peBarack Obama. Zvakare, iyi ndeimwe mimwe yehutakiti yezvidzidzo zvisingagadziri zvisingagoneki uye zvisingakanganisi uye inoyeuchidza yeLittary Digest fiasco.

Mufananidzo 3.7: Nhamba yevanhu vanobvunzwa muna W. Wang et al. (2015) . Nokuti vakapindura vakanyorerwa kubva kuXBox, ivo vainyanya kuva vaduku uye zvichida kuva varume, maererano nevhoti mumusarudzo ye 2012. Yakagadzirirwa kubva kuna W. Wang et al. (2015) , chidzidzo 1.

Zvisinei, Wang uye vaaishanda navo vaiziva nezvematambudziko aya uye vakaedza kugadzirisa maitiro avo asiri randomushambadziro pakuita zviyero. Kunyanya, vakashandisa post-stratification , imwe nzira iyo inoshandiswawo kwose kwose kugadzirisa zviitiko zvingangodaro zvine zvikanganiso zvekugovera uye kwete-mhinduro.

Iko pfungwa huru yekunyora-stratification ndeyokushandisa ruzivo rubatsiro pamusoro pevanhu vanotarisirwa kuti vabatsire kuvandudza kuongororwa kunobva kubva muenzaniso. Apo pavanoshandisa post-stratification kuita zviyero kubva kune yavo isingabviri muenzaniso, Wang uye mushandi pamwe naye vakagura vanhu muzvikwata zvakasiyana, vakafungidzira kutsigirwa kwaB Obama muboka rimwe nerimwe, uye vakatora chiyero chakarehwa chemazana ekufungidzirwa kweboka kuti zvive nekuenzanisa. Somuenzaniso, vangave vakaparadzanisa huwandu mumapoka maviri (varume nevakadzi), vakafungidzirwa kutsigirwa kwaB Obama pakati pevarume nevakadzi, uye vanofungidzirwa kubatsirana kwese kweB Obama kuburikidza nokutora chiyero chakareruka kuitira kuti vaone kuti vakadzi vanoita zvichikwira makumi mashanu kubva kuzana makumi mashanu kubva kune makumi mashanu kubva kuzana kubva muzana. Zvichida, kushandiswa kwe-post-stratification kunobatsira kugadzirisa kusaenzaniswa kwemuenzaniso nekuunza ruzivo rwebetsero pamusoro pehukuru hwemaboka.

Chinokosha chekunyora-stratification ndechokuumba mapoka akakodzera. Kana uchikwanisa kuisa huwandu hwevanhu muzvikwata zvakasiyana-siyana zvakadai kuti mhinduro dzekupindura dzakangofanana kune vose muboka rimwe nerimwe, uye kushambadzira kwemashure kunobereka maonero asina kuenzana. Mune mamwe mazwi, kutarisa-kutarisa kuburikidza nehutano kuchaita kuti zvionekwe zvisingaverengeki kana varume vose vane mhinduro yekudzivirira uye vakadzi vose vane mhinduro imwechete. Iko kunofungidzirwa kunonzi maitiro e-homogeneous-response-propensities-mukati-makambani ekufungidzira, uye ini ndinorondedzera iyo zvishoma muzvinyorwa zvemasvomhu kumagumo echitsauko chino.

Zvechokwadi, zvinoratidzika kunge zvisingaiti kuti mhinduro dzakanaka dzichave dzakafanana kune vose varume nevakadzi vose. Zvisinei, maitiro e-homogeneous-response-propensities-mukati-mapoka maonero anova anonyanya kuoneka sezvo nhamba yemapoka inowedzera. Zvichida, zvinova nyore kuvhara vanhu muzvikwata zvakasiyana kana iwe ukavaka mamwe mapoka. Somuenzaniso, zvingaratidzika zvisingaiti kuti vakadzi vose vane mhinduro imwe chete, asi zvingaratidzika zvakajeka kuti kune mhinduro imwechete yevamwe vakadzi vane makore 18-29, avo vakapedza chikoro, uye vari kugara muCalifornia . Nokudaro, sezvo nhamba yemapoka anoshandiswa mukugadzira-stratification inowedzera, mafungiro aidiwa kutsigira nzira yacho inonzwisisika. Zvichipa chokwadi ichi, vatsvakurudzi vanowanzoda kuumba nhamba yakawanda yemapoka e-post-stratification. Zvisinei, sezvo nhamba yemapoka inowedzera, vanotsvakurudza vanopinda mune dambudziko rakasiyana: data sparsity. Kana paine nhamba shomanana yevanhu muboka rimwe nerimwe, zvinofungidziro zvichange zvisingazivikanwi, uye mumamiriro ezvinhu akaipisisa apo pane boka risingabvunzurwi, uye shure kwe-stratification inopera zvachose.

Pane nzira mbiri dzinobuda mumamiriro aya ehupikano pakati pekugadzirisa kwema-homogeneous-response-propensity-mukati-mapoka maonero uye chido chekuenzanisa kwemazana ekuenzanisa muboka rimwe nerimwe. Kutanga, vatsvakurudzi vanogona kuunganidza soro, yakasiyana-siyana, iyo inobatsira kuchengetedza zviyero zvakaenzana zvekuenzanisa muboka rimwe nerimwe. Chechipiri, vanogona kushandisa imwe nyanzvi yakawanda yekuenzanisa maitiro ekugadzira kuenzanisa mukati memapoka. Uye, chaizvoizvo, dzimwe nguva vatsvakurudzi vanoita zvose, saWin nevakashanda navo vakaita nekunzvera kwavo sarudzo vachishandisa vapindura kubva kuXbox.

Nemhaka yokuti vakanga vachishandisa nzira isingakwanisi kuenzanirana nemakambani ekubvunzurudza makombiyuta (ini ndichataura zvakawanda pamusoro pekubvunzurudzwa kwekombiyuta munharaunda 3.5), Wang uye avo vaishanda navo vakanga vane mari shoma shoma yekuunganidza, yakavabatsira kuti vawane mashoko kubva ku 345 858 vatori vechikamu , nhamba huru nemitemo yekusarudzwa kwesarudzo. Izvi zvakakura masikirwo emasikirwo akavabatsira kuti vagadzire nhamba yakawanda yemapoka ekudzikamisa. Kunyange zvazvo kuiswa-stratification kunowanzobatanidza kuisa vanhu mumazana emapoka, Wang uye avo vaishanda navo vakaparadzanisa huwandu mumapoka evanhu 176,256 anotsanangurwa nehutano (2 mapoka), dzinza (4 maitiro), makore (4 maitiro), dzidzo (4 maitiro), nyika (51 mapoka), party ID (3 zvikamu), pfungwa (3 makarita), uye 2008 vheti (3 makero). Mune mamwe mazwi, maitiro avo makuru ekuenzanisa, ayo akashandiswa nekutengwa kwemari yakaderera, akavabatsira kuti vanyatsofungisisa mukufungidzira kwavo.

Kunyange na 345 858 vatori vechikamu vakasiyana-siyana, zvisinei, pakanga paine mazhinji, mapoka akawanda ayo Wang uye avo vaaishanda navo vakanga vasina vanenge vapindura. Saka, vakashandisa nzira inonzi " multilevel regression" yekufungidzira kutsigirwa kweboka rimwe nerimwe. Chaizvoizvo, kuenzanisa kutsigirwa kwaBacca mukati meboka rimwechete, mutemo we multilevel wakabatanidza mashoko kubva kumapoka akawanda akabatanidzwa. Semuenzaniso, fungidzira kuedza kufungidzira kutsigira kwaBabby pakati pevakadzi vechiSpanish pakati pemakore gumi nemana nemakumi mapfumbamwe nemakore makumi maviri nemashanu, avo vari veporoji vadzidza, avo vakanyoreswa Demochikiti, avo vanozviti vakazvimiririra, uye ivo vakabvumira Obama muna 2008. Izvi ndizvo chaizvo , boka rakanyatsotsvaga, uye zvinokwanisika kuti hakuna munhu ari muzaniso ane zviitiko izvi. Nokudaro, kuita zvikwereti pamusoro peboka iri, kutonga kwemarudzi akawanda kunoshandisa nhamba yekuenzanisa kuunganidza pamwe pamwe nekufungidzirwa kubva kuvanhu vari mumapoka akafanana.

Nokudaro, Wang uye avo vaishanda navo vakashandisa nzira iyo yakabatanidza kutonga kwakasiyana-siyana uye shure kwe-stratification, saka vakadana mazano avo akawanda ekudzikisa nekunyora-stratification kana, zvakanyanya rudo, "Mr. P. "Apo Wang uye avo vaishanda navo vakashandisa Mr. P. kuti vaenzanise kubva kuXBox isingagoni kuenzanisa, vakagadzira kufungidzira zvikuru pedyo nehutsigiro hwose iyo Obama akagamuchira mumasarudzo e2012 (chirevo 3.8). Zvechokwadi kukosha kwavo kwakange kwakarurama kudarika huwandu hwemagariro evanhu vemagariro evanhu. Nokudaro, munyaya iyi, kuchinja kwezviverengero-kunyanya Mr. P.-vanoita kuita basa rakanaka kugadzirisa kusavhiringidza mune zvisingabviri kudarika; kukanganisa kwaive kuoneka zvakajeka paunotarisa kuongororwa kubva pane zvisiri izvo zve Xbox data.

Mufananidzo 3.8: Inofanirwa kubva kuna W. Wang et al. (2015) . Kusagadziriswa XBox sampu yakabudisa kusaridzika kwakakwana. Asi, iyo yakakosha XBox samples yakagadzira kuenzanisa kuti yakanga yakarurama kupfuura yevhareji yezvichida-based telephone tsvakurudzo. Yakagadzirirwa kubva kuna W. Wang et al. (2015) , zvikamu 2 ne3.

Kune zvidzidzo zviviri zvinobva pakudzidza kwaWang uye vashandi. Kutanga, sarudzo dzisingaenzaniswi dzisingakwanisi dzinogona kutungamirira kukufungidzira kwakaipa; ichi chidzidzo icho vatsvakurudzi vakawanda vakambonzwa kare. Chidzidzo chechipiri, zvisinei, ndechokuti zvisingabviri zvidzidzo, kana zvakaongororwa zvakajeka, zvinogona kunyatsobudisa mazano akanaka; Zvisirizvo zvisingabviri zvidzidzo hazvidi kutungamirira kune chimwe chinhu chakafanana neLittary Digest fiasco.

Kuenderera mberi, kana uri kuedza kusarudza pakati pekushandisa mikana yekuenzanisira nzira uye yekusagadzikana sampling nzira yaunosangana nesarudzo yakaoma. Dzimwe nguva vatsvakurudzi vanoda kutonga nekukurumidza (semuenzaniso, nguva dzose shandisa nzira dzemaitiro ekuenzanisa), asi zviri kuramba zvichioma kupa mutemo wakadaro. Vanotsvakurudza vanotarisana nesarudzo yakaoma pakati pezvimwe zvinogona kuenzanisirwa nzira yekuita-izvo zviri kuwedzera kunodhura uye kure nemigumisiro yezvidzidzo inofananidzira kushandiswa kwavo-uye kwete-zvingave zvingashandiswa-shanduro nzira-dzinodhura uye dzinokurumidza, asi dzisinganyanyi kuzivikanwa uye dzakasiyana-siyana. Chinhu chimwe chakajeka, zvisinei, ndechekuti kana iwe uchikamanikidzwa kushanda pamwe chete nemasikirwo asingasviki kana zvisiri izvo zvinoratidzika zvemashoko makuru (funga zvakare kuChitsauko 2), zvino pane chikonzero chakasimba chekutenda kuti kuongororwa kwakaitwa uchishanda-stratification uye michina yakabatana ichava nani kudarika kusagadziriswa, zviyero zvitsva.