2.4.3.1 Natural kuedza
Natural kuedza kushandisa anongoitika zviitiko munyika. kurongwa chiitiko + nguva dzose-pasi date hurongwa = rwokuzvarwa chiedzwa
Kiyi randomized dzinodzorwa kuedza kugonesa wakanaka kuenzanisa ndiyo randomization. Zvisinei, dzimwe nguva chinhu chinoitika munyika kuti vanotova kunoshanda. vanhu randomly kana kusvika randomly kunorapwa siyana. Mumwe pachena mienzaniso nzira yokushandisa rwokuzvarwa kuedza kunobva pakutsvakurudza pamusoro Angrist (1990) kuti anoyera mugumisiro mabasa nemauto zvakaoma.
Munguva yehondo pakati Vietnam, United States vakawedzera kukura muuto rayo kuburikidza ubate. Kuti kusarudza vagari aizonzi kupinda pabasa, hurumende US akabata rotari. Ose birthdate akanga Rinomiririrwa kapepa, uye mapepa aya akaiswa mu hombe girazi gaba. Sezvinoratidzwa muna Figure 2.5, Miti ava mapepa vakanyengerwa kubva muchirongo imwe panguva kuziva kuti majaya aizonzi kushumira (vakadzi vechiduku havana pasi gwaro). Pachishandiswa migumisiro, varume vakaberekwa musi waSeptember 14 vakatanga kunzi, varume vakaberekwa musi April 24 vakadanwa wechipiri, uye zvichingodaro. Pakupedzisira, muna rotari ichi, varume vakaberekwa pamazuva 195 akasiyana makadanirwa basa apo vanhu vakaberekerwa pamazuva 171 havana kunzi.
Figure 2.5: Congressman Alexander Pirnie (R-NY) nokudhirowa capsule nokuda Selective Service gwaro rokutanga musi waDecember 1, 1969 Joshua Angrist (1990) zvikabatanidzwa gwaro rotari pamwe zvakaoma mashoko kubva Social Security Administration kufungidzira migumisiro rechiuto pamusoro zvakaoma. Uyu ndiwo muenzaniso kutsvakurudza vachishandisa dzinongoitika chiedzwa. Source: Wikimedia Commons
Kunyange zvazvo zvingasava pakarepo pachena, ubate rotari ane dzinonetsa kufanana munhu randomized kudzorwa kuedza: zvose ezvinhu vechikamu vari randomly basa kugamuchira kurapa. Kana gwaro rotari, kana tiri kufarira kudzidza migumisiro gwaro-kukodzera uye muchiuto unozotevera basa musika zvakaoma, tinogona enzanisa zvaitika vanhu vane birthdates vakanga pazasi rotari cutoff (semuenzaniso, September 14, April 24, etc.) pamwe zvaitika vanhu vane mazuva okuzvarwa zvakanga zvakaenzana cutoff (semuenzaniso, February 20, December 2, etc.).
Sezvo kurapwa ichi ekuzvarwa vaitorwa kwave randomly basa, tinogona zvino kuyera mugumisiro kurapa ichi chero zvaizoitika kuti yave akayera. Somuenzaniso, Angrist (1990) zvikabatanidzwa mashoko pamusoro akanga randomly kusarudzwa muna gwaro pamwe mari Data kuti ikaunganidzwa neDare Social Security Administration kuti kugumisa kuti mari yerusununguko chena vanenge 15% shoma kupfuura mari akafanana vasiri vakamborwa . Vamwe vatsvakurudzi vakashandisa yakafanana uchiwanzobvunzwa uyewo. Somuenzaniso, Conley and Heerwig (2011) zvikabatanidzwa mashoko pamusoro akanga randomly kusarudzwa muna gwaro neimba Data inounganidzwa kubva 2000 Census uye 2005 American Community Survey uye vakawana kuti izvozvo refu pashure gwaro, paiva zvishoma-refu mugumisiro muchiuto siyana zvaitika dzakadai sedzimba gavhuna (rinotukwa maringe kurendesa) uye chokugara kugadzikana (mikana pokuti vakatamira zvapfuura makore mashanu).
Sezvinoratidzwa nomuenzaniso uyu unoratidza, dzimwe nguva zvamagariro, matongerwo, kana masimba kusika kuedza kana pedo-kuedza zvinogona leveraged kubudikidza nevatsvakurudzi. Kazhinji zvakasikwa kuedza ndiyo nzira yakanakisisa kufungidzira chikonzero-uye-kushanda ukama muzviruva kwazvisina yetsika kana zvinoshanda kumhanya randomized rinodzorwa kuedza. Ndivo chinokosha makundiro aaizoita kuziva wakanaka kuenzanisa mune dzisiri experimental mashoko. Izvi kutsvakurudza nzira inogona muchidimbu mukana wokuti vanhu vanga ichi:
\ [\ chinyorwa {anongoitika (kana sokunge anongoitika) chiitiko} + \ rugwaro {nguva dzose-pasi date rukova} = \ chinyorwa {dzinongoitika kuedza} \ qquad (2.1) \]
Zvisinei, Kuongororwa dzinongoitika kuedza inogona kunyatsonanga runonyengera. Somuenzaniso, panyaya iri Vietnam kunze, kwete munhu wose aiva nekubatwa-kodzera vakazoguma kushumira (kwaiva zvakasiyana-siyana vasabatanidzwe). Uye, panguva imwe chete, vamwe vanhu vakanga vasina kunyora-vanokodzera zvakazvipira basa. Zvaiita sokuti ari kurapwa yavasina idzva zvinodhaka, vamwe vanhu vari muboka kurapwa haana kutora mushonga wavo uye vamwe vanhu vari kudzora boka zvimwe vakagamuchira zvinodhaka. dambudziko iri, wakadana vaviri-kuzviitirwa noncompliance, uyewo mamwe matambudziko akawanda zvinorondedzerwa kuchakurukurwa zvakadzama zvimwe yakarumbidza mukuverenga pakupera chitsauko chino.
Nzira yokutora mukana sezvingatarisirwa kuitika chero basa inotanga digitaalinen zera, asi kuwanda guru mashoko anoita nzira iyi nyore kushandisa. Kamwe here kuti vamwe kurapwa akumbirwa randomly, hombe mashoko anogona kupa zvaizoguma Data raunoda kuti kuenzanisa migumisiro vanhu vari kurapwa uye masimba ezvinhu. Somuenzaniso, mubhuku rake kudzidza migumisiro gwaro uye basa rechiuto, Angrist aishandisa zvakaoma zvinyorwa kubva Social Security Administration; pasina izvi zvaizoguma data, ake kudzidza zvaisazova zvichikwanisika. Panyaya iyi, Social Security Administration ndiyo nguva dzose-iri guru date kunobva. Sezvo vakawanda kwaita dzakaunganidza mashoko manyuko zvivepo, tinozova Mugumisiro Data anogona kuyera migumisiro kuchinja akasikwa exogenous kushanduka.
Kuenzanisira nzira iyi digitaalinen zera, ngatikurukurei Mas uye Moretti vake (2009) kwezvokufuka tsvakurudzo pamusoro mugumisiro nevezera pamusoro kwezvinhu. Kunyange zvazvo vangatarira pamusoro pemvura zvakasiyana pane kudzidza Angrist pamusoro migumisiro Vietnam Draft, mune mamiriro vose vanotevera muenzaniso eq. 2.1.
Mas uye Moretti akayera sei vezera sei negoho vashandi. Kune rimwe divi, ane zvakaoma kushanda kufurirwa akutungamirirei vashandi kuwedzera negoho kwavo nokuda kufanana nevezera rako. Kana, Ukuwo, munhu zvakaoma kushanda kufurirwa akutungamirirei vamwe vashandi kuti varembedze kure kunyange zvakawanda. The pachena nzira kudzidza kufurirwa KUENDERANA negoho yaizova randomized kudzorwa kuedza apo vashandi vari randomly ndinoshandira mumapoka vane vanoita zvakasiyana zvibereko siyana uye zvichiguma nezvibereko kunoyerwa vose. Vatsvakurudzi Zvisinei, regai kudzora purogiramu vashandi chero mabhizimisi chairo, uye saka Mas uye Moretti aifanira kuvimba dzinongoitika kuedza iyo kwakaitika imwe Supermarket.
Kufanana eq. 2.1, kudzidza kwavo aiva zvikamu zviviri. Chokutanga, vakashandisa matanda kubva Supermarket Checkout gadziriro kuti chaiwo, munhu, uye nguva dzose-pamusoro mwero negoho: uwandu zvinhu tarisa pa wechipiri. Uye, wechipiri, nemhaka panzira kusaronga chakaitwa panguva Supermarket ichi, vane pedo kurongwa nomuvhenganiswa vezera. Nemamwe mashoko, kunyange zvazvo kusaronga pamusoro cashiers hakubvi pakutsvaga munhu rotari, zvakanga chaizvoizvo chero. In tsika, kusatya kwatinako muna dzinongoitika kuedza kakawanda dzavo dzose ndedzechokwadi pamusoro plausibility iri "se-kana" chero kutaura. Kushandisa ichi anongoitika kushanduka, Mas uye Moretti vakawana kuti kushanda dzakakwirira negoho nevezera anowedzera kwezvinhu. Uyezve, Mas uye Moretti akashandisa kukura uye hunova dataset yavo kufamba mhiri uchimutarira pamusoro chikonzero-uye-zvazviri kuongorora kukosha anokunyengedzera nyaya mbiri: heterogeneity pamusoro kushanda ichi (iro aigadzira vashandi ndiwo mugumisiro hombe) uye mashandiro seri mugumisiro (nei kuva mukuru zvibereko vezera dzinotungamirira dzakakwirira kwezvinhu). Isu achadzokera izvi zviviri dzinokosha-heterogeneity kurapwa migumisiro zvenhengo-muChitsauko 5 patinokurukura kuedza zvizere.
Generalizing kubva zveBhaibheri zvinokonzerwa Vietnam Draft pamusoro zvakaoma uye kudzidza kushanda vezera iri negoho, Table 2.3 muchidimbu zvimwe zvidzidzo zvine ichi mamiriro chaiwo chete: achiedza nguva dzose-pasi date panobva kuyera matambudziko nevamwe chiitiko . Sezvo Table 2.3 inojekesa, njodzi dzinongoitika kuedza zviri kwose kwose kana iwe chete munoziva sei kutsvaka kwavari.
| , zvinhu pfungwa | Source rwokuzvarwa chiedzwa | Nguva dzose-pamusoro date mabviro | Citation |
|---|---|---|---|
| Nyatsotarira KUENDERANA negoho | kusaronga muitiro | Checkout date | Mas and Moretti (2009) |
| Friendship inotungamirirwa | madutu | Phan and Airoldi (2015) | |
| Kupararira manzwiro | mvura | Coviello et al. (2014) | |
| Nyatsotarira kunyatsotarira zveupfumi anotamisa | nokudengenyeka | Mobile mari date | Blumenstock, Fafchamps, and Eagle (2011) |
| Personal kunwa maitiro | 2013 US hurumende shutdown | pachako mari date | Baker and Yannelis (2015) |
| Kwoupfumi recommender nehurongwa | siyana | Browsing date pana Amazon | Sharma, Hofman, and Watts (2015) |
| Mugumisiro kuomera vana vasati vaberekwa | 2006 VaIsraeri-Hezbollah hondo | Birth zvinyorwa | Torche and Shwed (2015) |
| Kuverenga kuzvibata Wikipedia | Snowden kuzarurirwa | Wikipedia matanda | Penney (2016) |
In tsika, vatsvakurudzi vanoshandisa nzira mbiri dzakasiyana dzokuwana dzinongoitika kuedza, zvose zvinogona kuva zvibereko. Vamwe vatsvakurudzi kutange nguva dzose-pamusoro date mabviro uye kutsvaka anongoitika zviitiko munyika; vamwe kutanga anongoitika zviitiko munyika uye kutsvaka zvinyorwa date kuti andobata was yavo. Pakupedzisira, ona kuti simba rokudzora kuedza kunobva haana kubva Sophistication ari nhamba pachisara asi kubva kutarisira mune kuziva kwakanaka kuenzanisa akasikwa ane mhanza tsaona nhoroondo.
