3.4.2 Non-fungidziro ivhu: weighting
Nevasiri fungidziro ivhu, zvokuyeresa anogona kugadzirisa nokumonyaniswa anokonzerwa rakatora zvakabudiswa rikurumidze.
Saizvozvowo kuti vatsvakurudzi uremu mhinduro kubva fungidziro ivhu, vanogona vo uremu mhinduro kubva asiri fungidziro ivhu. Somuenzaniso, sezvo rinogona kutsiva CPS, fungidzira kuti iwe akaisa mureza achigadzira pamusoro zviuru Websites rokutsvaka vatori vechikamu kuti kuongorora kuti vanofungidzira urovha unodiwa. Nomuzvarirwo, ungadai vasinganyatsozvibvumi kuti nyore zvinoreva pamusoro mharidzo yako yaizova Zvinofungidzirwa kuti kwemabasa mwero wakanaka. kasingaperi Your zvichida nokuti munofunga kuti vamwe vanhu vane vangangoramba kupedza ongororo yako pane vamwe. Somuenzaniso, vanhu vasingabvumi kupedza nguva yakawanda padandemutande kashoma kupedza ongororo yako.
Sezvatakaona rokupedzisira chikamu Zvisinei, kana tichiziva kuti mharidzo akasarudzwa-sezvatinoita pamwe fungidziro ivhu-ipapo tinogona kubvisa nokumonyaniswa anokonzerwa zvakabudiswa rikurumidze. Zvinosuruvarisa kana tichishanda nevasiri fungidziro ivhu, hatizivi sei mharidzo akasarudzwa. Asi, tinogona kuita zvekungofungira pamusoro zvakabudiswa kwacho uye ipapo kushandisa weighting saizvozvo. Kana zvekungofungira ava kwakarurama, ipapo weighting achabvisa nokumonyaniswa anokonzerwa zvakabudiswa rikurumidze.
Somuenzaniso, fungidzira kuti pakupindura kwenyu mureza achigadzira, iwe basa 100,000 vakabvunzwa. Zvisinei, imi hamutendi kuti izvi 100,000 vakabvunzwa vari nyore kurongwa nzwisa American vakura. Kutaura zvazviri, kana iwe enzanisa vakabvunzwa enyu US vakawanda, unoona kuti vanhu vanobva vamwe inoti (semuenzaniso, New York) ndivo vanhu pamusoro dzinomiririrwa uye kuti kubvira vamwe inoti (semuenzaniso, Alaska) vari pasi-kumiririrwa. Nokudaro, urovha mwero mharidzo wako zvichida kuva vanofungidzira akaipa kwemabasa mwero kubaya vemo.
Imwe nzira rokugadzirisa kukanganiswa kuti zvakaitika zvakabudiswa zvinoitawo kuti ndipe Zviidzo kune mumwe munhu; repasi Zviidzo vanhu vanobva rinoti zviri pamusoro-hunomirirwa mharidzo (semuenzaniso, kuNew York) uye yakakwirira Zviidzo vanhu vanobva rinoti vari pasi-hunomirirwa mharidzo (semuenzaniso, Alaska). More zvakananga, uremu nerimwe respondent wakabatana hwakapararira kwenyu mharidzo hama kuti kuwanda kwavo muna US vemo. Izvi weighting nzira inonzi post-stratification, uye pfungwa pakupima vanofanira akuyeudzirei muenzaniso Section 3.4.1 apo vakabvunzwa kubva Rhode Island vakapiwa shoma uremu pane vakabvunzwa kubva kuCalifornia. Post-stratification zvinoda kuti unoziva zvakakwana kuisa vakabvunzwa ako mumapoka uye kuziva inorwara kupfura vemo muboka rimwe nerimwe.
Kunyange zvazvo weighting pamusoro mukana mharidzo uye asiri mukana yokuenzanisira hamushanduki nyanzvi (ona zvekushandisa okuwedzera), vanoshanda zvakanaka mumamiriro ezvinhu akasiyana. Kana mutsvakurudzi ane akakwana fungidziro yokuenzanisira (kureva, hapana nhau kukanganisa uye asina asiri response), ipapo weighting ichabereka unbiased inofungidzirwa kuti unhu zvose nguva dzose. yokungotaura vimbiso iyi simba Ndokusaka vanotsigira fungidziro ivhu kuvawana anoyevedza. Ukuwo, weighting asiri fungidziro ivhu kuchangoita zvibereko unbiased inofungidzirwa kuti unhu zvose kana kufarira propensities zvakafanana nokuti munhu wose ari muboka rimwe nerimwe. Nemamwe mashoko, achifunga kuti muenzaniso wedu, vachishandisa post-stratification richabereka unbiased inofungidzirwa kana wose muNew York ane zvakafanana ndingangokuvara pokuita uye vose Alaska ane zvakafanana ndingangokuvara pokuita uye zvichingodaro. Kubvuma uku kunonzi homogeneous-mhinduro-propensities-mukati-mapoka kubvuma, uye ane basa rinokosha nokuziva kana post-stratification vachashanda zvakanaka non-fungidziro ivhu.
Zvinosuruvarisa pamuenzaniso wedu, homogeneous-mhinduro-propensities-mukati-mapoka kubvuma sokudaro kuti ndezvechokwadi. Kureva, zvinoita sokudaro kuti vose Alaska ane zvakafanana ndingangokuvara yokuva ongororo yako. Asi, pane zvinhu zvitatu zvinokosha zvokufunga pfungwa pamusoro post-stratification, zvose kuiita seanotora zvinovimbisa.
Chokutanga, homogeneous-mhinduro-propensities-mukati-mapoka kubvuma hunowedzera anobata sezvo nhamba mapoka inowedzerawo. Uye, vaongorori hakugumiri kumapoka chete kwakavakirwa chete nzvimbo divi. Somuenzaniso, tinogona kuumba mapoka kwakavakirwa mamiriro, zera, bonde, uye azvipire dzidzo. Zvinoita sokuti vakawanda anobata kuti pane homogeneous kufarira propensities mukati boka 18-29, munhukadzi, vanenge vapedza kudzidza pakoreji vaigara Alaska kupfuura mukati boka vose vanhu vaigara Alaska. Saka, sezvo nhamba mapoka yaishandiswa post-stratification kuwedzera, zvekungofungira vaifanira vanoritsigira kuva musoro. Wapiwa chokwadi ichi, zvinoita seboka vaongorori angada kusika akawandisa mapoka nokuda post-stratification. Asi, sezvo nhamba mapoka inowedzera, vaongorori vanomhanya vachipinda yakasiyana dambudziko: date sparsity. Kana pane vashoma vanhu vari muboka rimwe nerimwe, ipapo kufungidzira zvichava zvikuru isingavimbiki, uye zvakanyanyisa nyaya apo pane boka kuti haana vakabvunzwa, ipapo post-stratification zvakakwana kwatanga pasi. Pane kubva ichi yokusafa nemakakatanwa pakati plausibility pamusoro homogeneous- akapindura-propensity-mukati-mapoka kubvuma uye kudiwa kunzwisisa mharidzo hukuru muboka rimwe nerimwe nzira mbiri. Imwe nzira iri kutamira yakagozha uwandu muenzaniso pakuverenga Zviidzo uye mumwe kuti vatore yakakura, zvimwe siyana mharidzo, iyo inobatsira nechokwadi kunzwisisa mharidzo hukuru muboka rimwe nerimwe. Uye, dzimwe nguva vatsvakurudzi itai zvose, sezvo Ndichange tsanangura zvizere pazasi.
A yechipiri nezvayo apo kushanda post-stratification nevasiri mukana ivhu ndechokuti homogeneous-mhinduro-propensity-mukati-mapoka kubvuma rava kakawanda kwakaitwa apo kuongorora fungidziro ivhu. Chikonzero kuti kubvuma uku kunodiwa kuti ndingangokuvara ivhu uchidzidzira ndechokuti ndingangokuvara ivhu vane asiri Achipindura, uye Nzira inonyanya ukagadzirisa vasiri mhinduro iri post-stratification zvatsanangurwa pamusoro. Zvechokwadi, nokuti vaongorori vakawanda vape kubvuma hazvirevi kuti unofanira kuzviita zvakare. Asi, zvinoreva kuti kana tichienzanisa vasiri fungidziro ivhu kuti ndingangokuvara ivhu iri tsika, tinofanira kuyeuka kuti kuvimba zvekungofungira uye ebetsero mashoko kuitira kuti pave kufungidzira. Kazhinji zvine musoro ezvinhu, hapana chero kubvuma-isina ainoita inference.
Pakupedzisira, kana iwe nehanya Zvinofungidzirwa zvikurukuru-kwedu muenzaniso kwemabasa mwero-unofanira mamiriro kusimba pane homogeneous-Achipindura-propensity-mukati-mapoka kubvuma. Zvakananga, haufaniri kufunga kuti munhu wose ane zvakafanana mhinduro propensity, imi vanongoenda tisafunge kuti hapana kuwirirana pakati mhinduro propensity uye kushayikwa kwemabasa mwero mukati nerimwe boka. Zvechokwadi, kunyange mamiriro ichi kurukutika hachizotibati mune mamwe mamiriro ezvinhu. Somuenzaniso, fungidzira kupima kuwanda vokuAmerica kuti vanoita basa rokuzvipira. Kana vanhu vanoita basa rokuzvipira kazhinji vanobvuma kuva vari kuongorora, ipapo vatsvakurudzi vachatitaka zvakanyatsorongwa pamusoro-kufungidzira uwandu kwokuzvipira, kunyange kana vachiita post-stratification chinje, somugumisiro kuti zvakaratidzwa empirically kubudikidza Abraham, Helms, and Presser (2009) .
Sezvo yakanga yapfuura Ini ndikati, asiri fungidziro ivhu vanoonekwa ne kusava nechokwadi kukuru evanhu masayendisiti, muchidimbu nokuda kwebasa ravo mamwe kunyadzisa nokukundikana mumazuva pakutsvakurudza ongororo mangwanani. Muenzaniso pachena sei kure tauya nevasiri fungidziro ivhu ndiro kutsvakurudzawo Wei Wang, David Rothschild, Sharad Goel, uye Andrew Gelman kuti zvakarurama akapora mugumisiro 2012 US sarudzo vachishandisa asiri fungidziro nzwisa American Xbox vanoshandisa -a zviri vasiri kurongwa marapiro vokuAmerica (Wang et al. 2015) . Vaongorori basa vakabvunzwa kubva Xbox uchitamba mutambo wacho hurongwa, uye sezvo ungatarisira kuti Xbox mharidzo nokushapira munhurume nokushapira muduku: 18 - 29 gore vane vana vane makore vanoumba 19% kubva electorate asi 65% of Xbox mharidzo uye varume anoumba 47% pamusoro electorate uye 93% of Xbox mharidzo (Figure 3,4). Pamusana simba wevanotungamirira vakanga vaine kwavakarerekera izvi, yakatsvuka Xbox mashoko aiva murombo chokukomborerwa sarudzo anodzoka. Rakataura kukunda simba nokuda backer Romney vakati- pamusoro Barack Obama. Zvekare, ichi ndiwo mumwe muenzaniso enjodzi mbishi, unadjusted asiri fungidziro ivhu uye zvakafananidzirwa Mamwe mabhuku Digest Fiasco.
Figure 3.4: Demographics pane vari Wang et al. (2015) . Nokuti pane vakanga basa kubva Xbox, vakanga anowanzova vaduku uye kazhinji kuva munhurume, hama kuti vavhoti vari 2012 musarudzo.
Zvisinei, Wang uye nevamwe vaiziva matambudziko aya uye vakaedza uremu yevakapindura kururamisa nokuda zvakabudiswa rikurumidze. Kunyanya, vaishandisa yakagozha chimiro pambiru-stratification ndakakuyambirai. Zvinokurudzirwa kudzidza zvishoma zvakawanda pamusoro zvavaiita nokuti runovaka kunzwisisa pamusoro post-stratification, uye zvikurukuru shanduro Wang uye nevamwe vakashandisa ndechimwe chezvinhu zvinofadza nzira kuti weighting vasiri fungidziro ivhu.
In muenzaniso wedu nyore pamusoro kupima kwemabasa muChikamu 3.4.1, isu akakamura vanhu muzvikwata kwakavakirwa mamiriro dzokugara. Kusiyana neizvi, Wang uye nevamwe akakamura vanhu kupinda muzvikwata 176.256 kunorondedzerwa: chechikadzi (2 Mapato), rudzi (4 Mapato), zera (4 Mapato), dzidzo (4 Mapato), mamiriro (51 Mapato), bato ID (3 Categories), dzidziso (3 Mapato) uye 2008 vhoti (3 mhando). With zvakawanda nemapoka, vatsvakurudzi aitarisira kuti zvaizova kuwedzera zvichida kuti mukati nerimwe boka, akapindura propensity akanga uncorrelated vane rutsigiro Obama. Zvadaro, pane rokuvaka nomumwe-pamwero zviyereso, sezvatakaitira ari muenzaniso wedu, Wang uye nevamwe akashandisa muenzaniso yakaoma kufungidzira kuwanda kwevanhu vari muboka rimwe nerimwe kuti angavavhotera Obama. Pakupedzisira, ivo zvikabatanidzwa izvi boka inofungidzirwa rutsigiro pamwe anozivikanwa kukura nerimwe boka kubereka zvinofungidzirwa tikwanise azvipire rutsigiro. Nemamwe mashoko, ivo wakatemerwa akakwidza yevagari kupinda mapoka akasiyana, zvinofungidzirwa kutsigirwa nokuda Obama muboka rimwe nerimwe, uye akatora weighted avhareji dzeboka inofungidzirwa kuti pave kunopindirana kufungidzira.
Saka, huru dambudziko ravo kusvika kune vanofungidzira rutsigiro Obama neimwe mapoka aya 176.256. Kunyange zvazvo remadziro kwavo kwaisanganisira 345.858 nemamwe vechikamu akawandisa nemitemo sarudzo polling, vakange vari vazhinji mapoka akawanda Wang uye nevamwe vakanga anenge asina vakabvunzwa. Saka, kufungidzira kutsigirwa mune rimwe boka vaishandisa nzira inonzi multilevel regression pamwe post-stratification, izvo vanotsvakurudza akanyatsoti kudana Mr. P. Zvikurukuru, kuti vanofungidzira rutsigiro Obama mukati yakananga boka, Va P. madziva mashoko mazhinji kufanana mapoka. Somuenzaniso, funga rakaoma kupima ari kutsigira Obama pakati munhukadzi, vaitaura chiHispanic, pakati pemakore 18-29 okuberekwa, vari pakoreji vakapedza kudzidza, vari vakanyorwa Democrats, uyo kuzvidzora kutiziva sezvo moderates, uye akavhotera Obama muna 2008. Izvi ari chaizvo, zvikuru chaizvo boka, uye zvinokwanisika kuti hakuna pakati mharidzo pamwe unhu izvi. Naizvozvo, kuti kufungidzira nezveboka iri, Va P. madziva pamwe inofungidzira vanhu mumapoka akafanana chaizvo.
Kushandisa uku kuongorora nzira, Wang uye vatinoshanda navo vakakwanisa kushandisa Xbox asiri fungidziro yokuenzanisira kuti akatibvunzisisa kufungidzira zvinonyatsorehwa kutsigirwa Obama akagamuchira muna 2012 musarudzo (Figure 3.5). Kutaura zvazviri inofungidzirwa avo vaiva rakanyatsorurama pane uwandu hwezvinhu zvose zvabatanidzwa. nevanhuwo musarudzo. Saka, iyi nyaya, weighting-zvakananga Mr. P.-sokuti kuita basa rakanaka anoruramisa vakanga vaine kwavakarerekera mune asiri fungidziro date; vakanga vaine kwavakarerekera dziri kuoneka kana uchitarisa kufungidzira kubva unadjusted Xbox Data.
Figure 3.5: Zvinofungidzirwa kubva Wang et al. (2015) . Unadjusted Xbox yokuenzanisira yakabereka savazvo inofungidzirwa. Asi, weighted Xbox mharidzo yakabereka inofungidzirwa kuti yakanga yakarurama kupfuura avhareji fungidziro anotsanangura runhare kuongorora.
Pane zvidzidzo zviviri huru kubva pakudzidza Wang uye nevamwe. Chokutanga, unadjusted asiri fungidziro ivhu kungaita nokufungidzira yakaipa; ichi chidzidzo kuti vaongorori vakawanda vakanzwa pamberi. Zvisinei, chidzidzo chechipiri ndechokuti vasiri fungidziro ivhu, kana weighted zvakanaka, zvinogona chaizvoizvo kubereka inofungidzirwa zvikuru zvakanaka. Kutaura zvazviri, inofungidzirwa avo vaiva rakanyatsorurama kupfuura vanofungidzira kubva pollster.com, ane aggregation zvikuru zvetsika sarudzo musarudzo.
Pakupedzisira, pane zvinokosha zvausingakwanisi kuti chii chatingadzidza pane uyu zvakananga kudzidza. Just nekuti post-stratification aishanda zvakanaka zvikurukuru nyaya ino, hapana vimbiso kuti zvichava kushanda zvakanaka dzimwe nguva. Kutaura zvazviri, sarudzo dziri zvichida mumwe nyore pazviruva nokuti pollsters vave kudzidza musarudzo kweanenge makore 100, pane nguva dzose inofambiswa (tinogona kuona uyo anokunda sarudzo), uye bato kuzivikanwa uye wevanotungamirira maitiro huri chokufenbera pamusoro kuvhota. Panguva iyi, tisina chakasimba dzidziso uye empirical ruzivo kuziva apo weighting kugadzirisa vasiri fungidziro ivhu richabereka inofungidzirwa zvakakwana yakarurama. Zvisinei, chimwe chinhu chiri pachena, zviri kana uri kumanikidzwa kushanda nevasiri fungidziro ivhu, saka pane chikonzero chakasimba chokudavira kuti akagadziridzwa inofungidzirwa zvichava nani pane non-kugadziridzwa inofungidzirwa.
