4.4.2 Heterogeneity yemiphumela yokwelashwa
Izivivinyo zivame ukukala umphumela wesilinganiso, kodwa umphumela cishe awufani nawo wonke umuntu.
Umqondo wesibili oyisihluthulelo wokuthutha ngaphesheya kokuhlolwa okulula kuyisimo se- heterogeneity yemiphumela yokwelashwa . Ukuhlolwa Schultz et al. (2007) sibonisa ngamandla ukuthi ukwelashwa okufanayo kungaba nomthelela ohlukene kanjani ezinhlobonhlobo zabantu (umfanekiso 4.4). Ezingxenyeni eziningi ze-analog, nokho, abacwaningi babegxile emiphumeleni yokwelashwa ejwayelekile ngoba kwakukhona inombolo encane yabahlanganyeli futhi abancane babengaziwa ngabo. Kokuhlolwa kwegedijithali, nokho, kuningi abahlanganyeli abaningi futhi abaningi baziwa ngabo. Kule ndawo ehlukile yedatha, abacwaningi abaqhubeka nokulinganisa imiphumela yokwelapha kuphela abazolahlekelwa izindlela lapho izilinganiso eziphathelene nokuphazamiseka kwemiphumela yokwelapha zinganikeza izinkomba mayelana nendlela ukwelashwa okusebenza ngayo, ukuthi kungathuthukiswa kanjani nokuthi kungabhekiswa kanjani kulabo okungenzeka bazuze.
Izibonelo ezimbili ze-heterogeneity yemiphumela yokwelashwa zivela ocwaningweni olwengeziwe kwiMibiko Yasekhaya Yasekhaya. Okokuqala, u- Allcott (2011) wasebenzisa usayizi omkhulu wesampula (imizi engu-600,000) ukuze aphinde ahlukanise isampula futhi alinganise umphumela we-Home Energy Report nge-decile yokusetshenziswa kwe-pre-treatment. Ngesikhathi Schultz et al. (2007) wathola umehluko phakathi kwabasebenzisi Allcott (2011) , u- Allcott (2011) wathola ukuthi kunezimpikiswano phakathi kweqembu elisindayo futhi elikhanyayo. Isibonelo, abasebenzisi abakhulu kunazo zonke (labo e-decile phezulu) bancishise ukusetshenziswa kwabo kwamandla kabili kunomuntu phakathi kweqembu elisetshenziswe kakhulu (isibalo 4.8). Ngaphezu kwalokho, ukulinganisa umphumela wokuziphatha kwangaphambi kokwelashwa kwaveza nokuthi kwakungekho nhlobo ye-boomerang, ngisho nabasebenzisi abakhulu kakhulu (isibalo 4.8).
Umdwebo 4.8: Imiphumela ye-Heterogeneity Allcott (2011) yokwelapha e- Allcott (2011) . Ukuncipha kokusetshenziswa kwamandla kwakuhlukile kubantu abahlukehlukene bokusetshenziswa kokuqala. Ishintshwe ku- Allcott (2011) , isibalo 8.
Esifundweni esilandelayo, Costa and Kahn (2013) inqume ukuthi ukuphumelela kwe-Home Energy Report kungahlukahluka ngokuvumelana nemibono yezombusazwe futhi ukuthi ukwelashwa kungase kubangele abantu ukuthi babe nemibono ethile yokwandisa ukusetshenziswa kwabo kagesi. Ngamanye amazwi, bacabange ukuthi i-Home Energy Reports ingase idale umphumela we-boomerang kwezinye izinhlobo zabantu. Ukuze kuhlolwe lokhu kungenzeka, iCosta neKahn bahlanganisa idatha ye-Opower nedatha ethengwe kumuntu wesithathu ohlanganisa ulwazi olufana nokubhaliswa kweqembu lezombangazwe, iminikelo yezinhlangano zemvelo, nokubamba iqhaza komndeni ezinkambisweni zamandla avuselelekayo. Ngalesi sitatimende sedatha, iKosta noKahn bathole ukuthi imibiko yamandla asekhaya yakhiqiza imiphumela efana kakhulu yabahlanganyeli abanezimfundiso ezahlukene; bekungekho ubufakazi bokuthi noma yiliphi iqembu libonise imiphumela ye-boomerang (umfanekiso 4.9).
![Umdwebo 4.9: Imiphumela ye-Heterogeneity yemithi yokwelapha eCosta naseKahn (2013). Isilinganiso esilinganiselwe sokwelashwa kwesilinganiso sesampula sonke si -2.1% [-1.5%, -2.7%]. Ngemuva kokuhlanganiswa kolwazi kusukela ekuhloleni ulwazi mayelana nemindeni, iCosta neKahn (2013) basebenzisa uchungechunge lwamamodeli amanani ukulinganisa umphumela wokwelashwa kwamaqembu aqondene nabantu. Izilinganiso ezimbili zihanjiswa eqenjini ngalinye ngoba ukulinganisa kuxhomeke kuma-covariates afakwe kumamodeli abo amanani (bheka amamodeli 4 no-6 kumatafula 3 no-4 eCosta naseKahn (2013)). Njengoba lesi sibonelo sibonisa, imiphumela yokwelapha ingahluka kubantu abahlukene kanye nokulinganiselwa kwemiphumela yokwelapha evela emafelini angamanani angancika emininingwaneni yalezo zithombe (Grimmer, Messing, naseWestwood 2014). Kuthathwa kusukela eCosta naseKahn (2013), amathebula 3 no-4.](figures/chapter4/bitbybit4-9_costa_energy_2013_tab4.png)
Umdwebo 4.9: Imiphumela ye-Heterogeneity yemithi yokwelapha Costa and Kahn (2013) . Isilinganiso esilinganiselwe sokwelashwa kwesilinganiso sesampula sonke si -2.1% [-1.5%, -2.7%]. Ngemuva kokuhlanganiswa kolwazi kusukela ekuhloleni ulwazi mayelana nemindeni, Costa and Kahn (2013) basebenzisa uchungechunge lwamamodeli amanani ukulinganisa umphumela wokwelashwa kwamaqembu aqondene nabantu. Izilinganiso ezimbili zihanjiswa eqenjini ngalinye ngoba ukulinganisa kuxhomeke kuma-covariates afakwe kumamodeli abo amanani (bheka amamodeli 4 no-6 kumatafula 3 no-4 Costa and Kahn (2013) ). Njengoba lesi sibonelo sibonisa, imiphumela yokwelapha ingahluka kubantu abahlukene kanye nokulinganiselwa kwemiphumela yokwelapha evela (Grimmer, Messing, and Westwood 2014) emininingwaneni yalezo zithombe (Grimmer, Messing, and Westwood 2014) . Kuthathwa kusukela Costa and Kahn (2013) , amathebula 3 no-4.
Njengoba lezi zibonelo ezimbili zibonisa, eminyakeni yobudala, singasuka ekuqhathaneni imiphumela yemithi yokwelapha isilinganiso sokulinganisa ukuphathwa kwemithi yokwelapha ngoba singaba nabambiqhaza abaningi futhi siyazi kabanzi ngalabo ababambiqhaza. Ukufunda nge-heterogeneity yemiphumela yokwelashwa kungenza kube lula ukubhekwa kokwelashwa lapho kuphumelela kakhulu, ukuhlinzeka ngamaqiniso avuselela ukuthuthukiswa kwezinkolelo ezintsha, futhi anikeze amacebo mayelana nezinqubo ezingenzeka, isihloko esiphendukela kuso manje.
