3.4 Ubani ukubuza
I-digital age eyenza isampuli kungenzeka ngokusebenza kanzima futhi idala amathuba amasha okungekho okungenakwenzeka.
Emlandweni wesampuli, kuye kwaba nezindlela ezimbili zokuncintisana: izindlela zezampula zezampula kanye nezindlela ezingezona ezenzekayo zokutadisha. Nakuba lezo zindlela zombili zazisetshenziswa ezinsukwini zokuqala zesampuli, kungenzeka ukuthi isampula sithinte, futhi abacwaningi abaningi bezenhlalakahle bafundiswa ukubheka isampula esingenakwenzeka ngamathemba amakhulu. Kodwa-ke, njengoba ngizochaza ngezansi, izinguquko ezidalwe yinkathi yedijithali zisho ukuthi sekuyisikhathi sokuba abacwaningi bacabange ngesampula esingenakwenzeka. Ngokuyinhloko, kungenzeka ukuthi isampula senze kanzima ukwenza ngokusebenza, futhi isampula esingenakwenzeka ukuthi isheshayo, eshibhile futhi esingcono. Ukuhlola okusheshayo futhi okungabizi nje akupheli kuphela: kunika amandla amathuba amasha njengenhlolovo evamile kaningi namasayizi amakhulu esampula. Isibonelo, ngokusebenzisa izindlela ezingenakwenzeka ukuthi i-Cooperative Congressional Election Study (CCES) ikwazi ukuba nabalingani abaphindwe izikhathi ezingaphezu kuka-10 kunezifundo zangaphambili besebenzisa isampuli esenzekayo. Isampula esinkulu kakhulu senza abacwaningi bezombangazwe bafunde ukuhlukahluka ekuziphatheni nasekuziphatheni kuwo wonke ama-subgroups nezimo zenhlalo. Ngaphezu kwalokho, konke lokhu okungeziwe kwafika ngaphandle kokunciphisa izinga lokulinganisela (Ansolabehere and Rivers 2013) .
Njengamanje, indlela eyinhloko yesampula yokucwaninga kwezenhlalakahle kungenzeka ukuthi sampula . Ngamathuba okuba nesampula, wonke amalungu eqembu elinqophile anethuba elingaziwa, elingenalo ilungelo lokuba nesampuli, futhi bonke abantu abathintekayo baphendule kulolu cwaningo. Uma lezi zimo zifinyelelwa, imiphumela enhle yemathempi inikezela ngokuqinisekisayo ukuthi ikhono lomcwaningi lokusebenzisa isampula ukwenza izinkomba mayelana nabantu abathintekayo.
Esimweni sangempela, noma kunjalo, izimo ezisekelwe kule miphumela azikwazi ukuhlangana nazo. Isibonelo, kunamaphutha okufakela njalo nokungahloniphi. Ngenxa yalezi zinkinga, abacwaningi bavame ukuba basebenzise ukulungiswa kwezibalo ezihlukahlukene ukuze benze ukulinganisa kusuka esampheni yabo kubantu ababhekiswe kuzo. Ngakho-ke, kubalulekile ukuhlukanisa phakathi kwamathuba okuba nesampula ku-theory , eneziqiniseko ezinamandla zokwenza izinto, kanye nokulinganisa okusemandleni okusebenza , okunganikezi iziqinisekiso ezinjalo futhi kuxhomeke ekuguqulweni kwezibalo ezihlukahlukene.
Ngokuhamba kwesikhathi, umehluko phakathi kwamathuba okulinganisa ematheksthini kanye nokuhlelwa kwesampula ekusebenzeni kuye kwanda. Isibonelo, izinga lokungahloniphi liye landa, ngisho nasezingeni eliphakeme, ukuhlola okubizayo (isibalo 3.5) (National Research Council 2013; BD Meyer, Mok, and Sullivan 2015) . Izinga lokungahloniphi liphakeme kakhulu ekuhloleni kwezingcingo zezohwebo-ngezinye izikhathi ngisho nangaphezulu kuka 90% (Kohut et al. 2012) . Lokhu kwanda ngokungenandaba kungasongela izinga lokulinganisa ngoba ukulinganisa kuncike ekutheni kunamaphesenti amanani abacwaningi abasebenzisa ukulungisa ukungahloniphi. Ngaphezu kwalokho, lezi zinciphisa izinga liye zenzeka naphezu kwemizamo ekhulayo yocwaningi abacwaningi ukuze balondoloze izinga eliphezulu lokuphendula. Abanye abantu besaba ukuthi lezi zindlela ezimbili zokunciphisa ikhwalithi kanye nezindleko ezikhulayo zisongela ucwaningo lwezocwaningo (National Research Council 2013) .
Umdwebo 3.5: Ukungahloniphi kuye kwaqhubeka ngokuqhubekayo, ngisho nasezinhlokweni eziphakeme ezibiza kakhulu (National Research Council 2013; BD Meyer, Mok, and Sullivan 2015) . Izinga lokungahloniphi liphakeme kakhulu ekuhloleni kwezingcingo zezohwebo, ngezinye izikhathi ngisho nangaphezulu kuka 90% (Kohut et al. 2012) . Lezi zindlela ezide zesikhathi eside ngaphandle kokungasho ukuthi ukuqoqwa kwedatha kuyabiza kakhulu futhi ukulinganisa kunokwethenjelwa kancane. Ishintshwe ku- BD Meyer, Mok, and Sullivan (2015) , isibalo 1.
Ngesikhathi esifanayo ukuthi kube nezinkinga ezikhulayo zezindlela zokwenza isampula, kuye kwaba nokuthuthuka okuthakazelisayo ezindleleni zezampula ezingenakwenzeka . Kunezindlela ezihlukahlukene zezindlela zezindlela zokulinganisa ezingenakwenzeka, kodwa into eyodwa abafana ngayo ukuthi ayinakukwazi ukulingana kahle nohlaka lwesibalo samathuba okungenzeka (Baker et al. 2013) . Ngamanye amazwi, ngezindlela zokungatheni ezingenakwenzeka akuwona wonke umuntu onokukwazi ukukwazi ukungena. Izindlela zokulinganisa ezingenakwenzeka ziba nedumela elibi phakathi kwabacwaningi bezenhlalakahle futhi zihlobene nokunye ukuhluleka okuphawulekayo kocwaningi abacwaningi, njenge- Literary Digest fiasco (okukhulunywe ngayo ekuqaleni) nokuthi "Dewey Inqothula iTruman," ukubikezela okungalungile mayelana ne-US ukhetho lukaMengameli luka-1948 (isibalo 3.6).
Umdwebo 3.6: UMongameli uHarry Truman ubambe isihloko sephephandaba elimemezele ngokungalungile ukunqotshwa kwakhe. Lesi sihloko sasisekelwe ekucatshangweni kwamasampuli (Mosteller 1949; Bean 1950; Freedman, Pisani, and Purves 2007) . Nakuba "u-Dewey ahlula uTruman" kwenzeka ngo-1948, kusekhona phakathi kwesinye isizathu abanye abacwaningi abangabazayo mayelana nezilinganiso zamasampuli angenakwenzeka. Umthombo: Harry S. Truman Library & Museum .
Olunye uhlobo lwezampula ezingenakwenzeka ukuthi lufanelekile eminyakeni yobudijithali ukusetshenziswa kwamapaneli enethiwekhi . Abacwaningi abasebenzisa amaphaneli e-intanethi bathembele kumhlinzeki othile wephaneli-ngokuvamile inkampani, uhulumeni, noma eyunivesithi-ukwakha iqembu elikhulu labantu abahlukahlukene abavuma ukukhonza njengabaphenduli bezinhlolovo. Laba bahlanganyeli bephaneli bavame ukuqashwa ngokusebenzisa izindlela ezihlukahlukene zokukhangisa ezifana nezikhangiso ze-banner. Khona-ke, umcwaningi angakhokha umhlinzeki wephaneli ukuze afinyelele isampula sabaphendula ngezici ezifisa (isb., Omele abantu abadala). Lawa mapaneli e-intanethi ayizindlela ezingenakwenzeka ngoba akuwona wonke umuntu owaziwayo, ongenayo i-nonzero yokufakwa. Nakuba ama-panel angenakwenzeka emaphandleni asetshenziswe kakade ngabacwaningi bezenhlalakahle (isib. I-CCES), kusekhona impikiswano mayelana nekhwalithi yezilinganiso ezivela kubo (Callegaro et al. 2014) .
Naphezu kwale mpikiswano, ngicabanga ukuthi kunezizathu ezimbili zokuthi kungani isikhathi senza ukuba abacwaningi bezenhlalakahle babuye bacabangele ukulinganisa okungenakwenzeka. Okokuqala, eminyakeni yobudijithali, kube khona intuthuko eminingi ekuqoqweni nasekuhlaziyweni kwamasampuli angenakwenzeka. Lezi zindlela ezintsha zihlukile ngokwanele ezindleleni ezibangele izinkinga esikhathini esedlule ukuthi ngicabanga ukuthi kunengqondo ukucabanga ngokuthi "kungenakwenzeka ukulinganisa i-2.0." Isizathu sesibili esenza abacwaningi bacabangele ukulinganisa okungenakwenzeka kungenxa yokuthi isampula kungenzeka umkhuba uba nzima nakakhulu. Uma kunamanani aphakeme angewona impendulo-njengoba kukhona ukuhlolwa kwangempela manje-amathrekhi wangempela wokufakwa kwabaphenduli awaziwa, futhi ngaleyo ndlela, amasampula okuba nesampuli namasampuli angenakwenzeka awafani nabacwaningi abaningi abaye bakholelwa.
Njengoba ngishilo ngaphambili, amasampula angenakwenzeka angabhekwa ngokucabangela okukhulu ngabacwaningi abaningi bezenhlalakahle, ngenxa yendima yabo kwezinye zezinhlupho ezidabukisayo kakhulu ezinsukwini zokuqala zocwaningo zocwaningo. Isibonelo esicacile sokuthi sifike kude kangakanani namasampula angenakwenzeka, ucwaningo lukaWei Wang, uDavid Rothschild, uSharad Goel no-Andrew Gelman (2015) okwakuthola kahle imiphumela yomkhankaso we-2012 wase-US ngokusebenzisa isampula esingenakwenzeka Abasebenzisi be-Xbox baseMelika-isampula esinqunyiwe sama-American. Abacwaningi babhalisa abaphendula kusukela ohlelweni lwezokudlala lwe-XBox, futhi njengoba ungalindela, i-Xbox isampula engumfana oyisisulu nabasolwa: abaneminyaka engu-18 kuya kwezingu-29 bakha u-19% we-electorate kodwa 65% we-Xbox isampula, namadoda yenza ama-47% we-electorate kodwa u-93% we-Xbox isampula (isibalo 3.7). Ngenxa yalezi zinsalela eziphezulu zabantu, i-Xbox idatha eyimfihlo yayiyisibonakaliso esimpofu sokubuyiswa kokhetho. Kwabikezela ukuthi uMitt Romney uzowunqoba kakhulu uBarack Obama. Nalapha, lokhu kungenye isibonelo sezingozi zamasampuli angenakulinganiswa, angakalungi futhi okukhumbuza i- Literary Digest fiasco.
Umdwebo 3.7: Amanani wabantu abaphendula W. Wang et al. (2015) . Ngenxa yokuthi abaphenduliwe baboshwa kusuka ku-XBox, cishe babebancane futhi kungenzeka ukuba babe besilisa, ngokuphathelene nabavoti okhethweni luka-2012. Ilandelwe kusuka ku- W. Wang et al. (2015) , isibalo 1.
Kodwa-ke, uWang kanye nozakwabo bebazi lezi zinkinga futhi bazama ukulungisela inqubo yabo yokungahleliwe engahleliwe lapho benza izilinganiso. Ngokuyinhloko, basebenzisa i- post-stratification , inqubo ebuye isetshenziswe kabanzi ukuze ilungise amasampula angenzeka ukuthi aneziphambeko zokuhlanganisa kanye nokungaphenduli.
Umqondo oyinhloko we-post-stratification ukusebenzisa ulwazi olusizayo mayelana nenani labantu abahlosiwe ukusiza ukuthuthukisa ukulinganisa okuvela kwisampula. Lapho usebenzisa i-post-stratification yokwenza izilinganiso esiteshini sabo esingenakwenzeka, u-Wang nomngane wakhe baqoqa abantu emaqenjini ahlukene, balinganisela ukusekela kuka-Obama eqenjini ngalinye, bese bethatha isilinganiso esilinganiselwe sesilinganiso seqembu ukuze kuvezwe isilinganiso esiphezulu. Isibonelo, bangahlukanisa umphakathi ngamaqembu amabili (amadoda nabesifazane), balinganisela ukusekela kuka-Obama phakathi kwamadoda nabesifazane, bese kulinganiselwa ukuthi basekela u-Obama ngokulinganisa isilinganiso sokulinganisa ukuze abesifazane benze up 53% we-electorate namadoda angu-47%. Cishe, ukulandelana kwe-post-stratification kusiza ukulungisa isampula esingalingani ngokuletha ulwazi oluwusizo mayelana nobukhulu bamaqembu.
Isihluthulelo sokuthumela i-post-stratification ukwakha amaqembu afanele. Uma ungakwazi ukuqeda abantu ukuba babe amaqembu ahambisanayo njengokuthi amandla okuphendula afana nawo wonke umuntu eqenjini ngalinye, ngakho-ke ukufakwa kwe-stratification kuzoveza izilinganiso ezingenakubalwa. Ngamanye amazwi, ukuhlelwa kokuhlelwa ngokobulili kuzoveza izilinganiso ezingenakubulungiswa uma wonke amadoda enamandla okuphendula futhi bonke abesifazane banokuphendula okufanayo. Lokhu kuthathwa kuthiwa yi- homogeneous-response-propensities-ngaphakathi-amaqembu ukucabanga, futhi ngikuchaza kancane emanzini wezinhlamvu ekupheleni kwalesi sahluko.
Yiqiniso, kubonakala sengathi akunakwenzeka ukuthi izimpendulo zokuziphendulela zizofana nazo zonke amadoda nabo bonke abesifazane. Kodwa-ke, ukuhlaziywa kwe-homogeneous-response-ngaphakathi-amaqembu kuthathwa ngokwengeziwe njengoba inani lamaqembu landa. Kancane, kuba lula ukusika abantu ukuba babe amaqembu afanayo uma udala amaqembu amaningi. Isibonelo, kungase kubonakale kungenakwenzeka ukuthi bonke abesifazane banokuphendula okufanayo, kodwa kungase kubonakale sengathi kukhona ukuphendula okufanayo okukhona kokuphendula kwabo bonke abesifazane abaneminyaka engama-18-29, abaphothule ekolishi, nalabo abahlala eCalifornia . Ngakho-ke, njengoba inani lamaqembu asetshenziswe ekulandelweni kokulandelana lithola likhulu, ukucabanga okudingekayo ukusekela indlela kube lula kakhulu. Njengoba kunikezwe leli qiniso, abacwaningi bavame ukudala inqwaba yamaqembu e-post-stratification. Kodwa-ke, njengoba inani lamaqembu landa, abacwaningi bangena enkingeni ehlukile: ukuhlukaniswa kwedatha. Uma kunabantu abambalwa kuphela eqenjini ngalinye, khona-ke izilinganiso ngeke ziqiniseke nakakhulu, futhi esimweni esibucayi lapho kukhona iqembu elingenabo abaphendulayo, ukulandelana kwe-post-stratification ngokuphelele kwehla.
Kunezindlela ezimbili ezivela kulokhu kuphazamiseka okukhona phakathi kokubaluleka kwe-homogeneous-response-propensity-ngaphakathi-amaqembu ukucabanga kanye nesidingo samasayizi wesampula afanelekayo eqenjini ngalinye. Okokuqala, abacwaningi bangakwazi ukuqoqa isampula enkulu, ehlukene kakhulu, esiza ukuqinisekisa ukuthi amasampuli amancane asetshenziswa kanjani eqenjini ngalinye. Okwesibili, bangasebenzisa imodeli eyinkimbinkimbi yokwenza izilinganiso ngaphakathi kwamaqembu. Futhi, eqinisweni, ngezinye izikhathi abacwaningi benza kokubili, njengoba uWang kanye nosebenza nabo benza ngokufunda kwabo ukhetho basebenzisa abaphenduli be-Xbox.
Ngenxa yokuthi babesebenzisa indlela yokulinganisa okungenakwenzeka ngamaphenyo alawulwa ikhompyutha (ngizokhuluma kabanzi mayelana nezingxoxo ezilawulwa yikhompiyutha esigabeni 3.5), uWang kanye nozakwethu babeneqoqo lemininingwane ephansi kakhulu, okwabenza bakwazi ukuqoqa ulwazi kusuka kwabangu-345,858 abahlanganyeli abayingqayizivele , inombolo enkulu ngezindinganiso zokuvota kokhetho. Lesi sayizi esampula samasampula senze ukuba bakwazi ukwakha inani elikhulu lamaqembu wokuthutha. Nakuba ukufakwa kwe-post-stratification kuhilela ukuhlukanisa abantu ngamakhulu amaqembu, uWang nozakwethu bahlukanisa abantu ngamaqembu angu-176,256 achazwa ubulili (izigaba ezimbili), ubuhlanga (izigaba ezine), iminyaka (4 imikhakha), imfundo (izigaba ezine), isimo (Izigaba 51), i-ID yenkampani (3 izigaba), i-ideology (3 imikhakha), kanye nevoti ka-2008 (izigaba ezintathu). Ngamanye amazwi, isayizi yabo yesampula enkulu, eyanikwe amandla ngokuqoqwa kwedatha ephansi, yabanikezela ukuba benze ukucabanga okucacile ngokwengeziwe kwinqubo yabo yokulinganisela.
Ngisho nabangu-345,858 abahlanganyeli abayingqayizivele, nokho, kwakunezinhlobo eziningi, amaqembu amaningi u-Wang nozakwabo abangazange baphendule. Ngakho-ke, basebenzisa inqubo ebizwa ngokuthi ukuphathwa kwe-multilevel ukulinganisa ukusekelwa eqenjini ngalinye. Ngokuyinhloko, ukulinganisa ukusekelwa kuka-Obama ngaphakathi kweqembu elithile, ukuguqulwa kwe-multilevel kuhlanganiswe ulwazi kusuka kumaqembu amaningi ahlobene eduze. Ngokwesibonelo, cabanga ukuzama ukulinganisa ukusekela kuka-Obama phakathi kwabesifazane abangama-Hispanics phakathi kweminyaka engu-18 no-29 ubudala, abaqeqeshwayo ekolishi, ababhalisiwe njengezidemokhrasi, abazisho ukuthi bangamengameli, futhi abavotela u-Obama ngonyaka ka-2008. , iqembu eliqondile kakhulu, futhi kungenzeka ukuthi akekho umuntu esampheni ngalezi zici. Ngakho-ke, ukwenza izilinganiso ngaleli qembu, ukuguqulwa kwe-multilevel isebenzisa imodeli yezibalo ukuhlanganisa izilinganiso ezihlangene ezivela kubantu abakumaqembu afanayo kakhulu.
Ngakho-ke, uWang kanye nosebenza nabo basebenzise indlela ehlanganisa ukuhlukumezeka kwe-multilevel kanye nokulandelana kwe-post-stratification, ngakho-ke baqamba ukukhishwa kwabo kwe-multilevel nge-post-stratification noma, ngokufudumele, "Mnu. P. "Lapho uWang kanye nosebenza nabo basebenzisa uMnu. P. ukwenza izilinganiso kusukela ku-sampula ye-XBox engekho ematfuba, bakhiqiza izilinganiso eziseduze kakhulu nokwesekwa okwasekelwa ngu-Obama okhethweni luka-2012 (isibalo 3.8). Eqinisweni ukulinganisa kwabo kwakunembile kunokwamaqembu omphakathi wombono wendabuko. Ngakho-ke, kulokhu, ukulungiswa kwezibalo-ikakhulukazi uMnu P.-kubonakala sengathi wenza umsebenzi omuhle ukulungisa ukungabi namathuba emininingwaneni engenakwenzeka; izinkanuko ezibonakala ngokucacile uma ubheka izilinganiso ezivela ku-Xbox idatha engalungisiwe.
Umdwebo 3.8: Kulinganiselwa ku- W. Wang et al. (2015) . Isampula ye-XBox engalungisiwe yenzelwe ukulinganisa okungalungile. Kodwa, isampula ye-XBox enesisindo sikhiqize izilinganiso ezazinembile kakhulu kunombono wezinhlolo zocingo ezisekelwe ematheni. Ilandelwe kusuka ku- W. Wang et al. (2015) , izibalo 2 no-3.
Kunezifundo ezimbili eziyinhloko ezivela ekutadisheni kukaWang kanye nozakwabo. Okokuqala, amasampuli angenakulinganiswa angenakwenzeka angabangela izilinganiso ezimbi; lokhu isifundo abacwaningi abaningi abazwile ngaphambili. Isifundo sesibili, noma kunjalo, ukuthi amasampuli angenakwenzeka, lapho ehlungwa kahle, angakwazi ukukhiqiza izilinganiso ezinhle; amasampuli angenakwenzeka akudingeki aqhubekele phambili okunye okufana ne- Literary Digest fiasco.
Ukuqhubeka phambili, uma uzama ukunquma phakathi kokusebenzisa indlela yokwenza isampula ongakwazi ukuyenza kanye nesimo esingenakwenzeka sampula ubhekene nokukhetha okunzima. Ngezinye izikhathi abacwaningi bafuna umthetho osheshayo nowunzima (isib. Sebenzisa njalo izindlela zezampula zempendulo), kodwa kunzima kakhulu ukunikeza umthetho onjalo. Abacwaningi babhekene nokukhetha okunzima phakathi kwezindlela zokwenza izampula ezenzakalweni-eziya ngokuya ezibizayo futhi ezikude nemiphumela yezinkolelo ezibonisa izindlela zabo zokusebenzisa-nezingahle zingenakwenzeka-ezingabizi futhi zishesha, kodwa zingaphansi futhi zijwayele kakhulu. Into eyodwa ecacile, noma kunjalo, ukuthi uma uphoqeleka ukuba usebenze ngamasampuli angenakwenzeka noma imithombo emikhulu yedatha engabonakali (cabanga emuva eSahlukweni 2), khona-ke kunesizathu esinamandla sokukholelwa ukuthi izilinganiso ezenziwe ngokusebenzisa ukufakwa kwe-stratification futhi amasu ahlobene azoba ngcono kunokungalungi, izilinganiso eziluhlaza.
