When Crowds Go Wrong: Bubbles, Cascades, and the Madness of Herds

Taru guda, kwanaki biyu masu banbanci

A cikin 1906, taron mutane 787 a wani baje kolin dabbobi na Ingilishi sun yi hasashen nauyin wani saniya har zuwa kusan kashi ɗaya na gaskiya — shaidar kafa na hikimar taruka, wanda muke bayarwa a cikakke a cikin labarin saniyar Galton. Kwanaki biyu da rabi kafin haka, tarukan 'yan kasuwa na Dutch masu kyau sun yi farashi na rare tulip bulbs zuwa manyan matakai kafin kasuwar ta rushe a cikin wata guda na Fabrairu. Irin wannan nau'in, irin wannan kayan tunani. Menene ke juyawa?

Bambancin ba shine basira ba, kuma ba shine son zuciya ba. Shi ne tsari. Masu ziyara na Galton sun rubuta hasashen su a cikin sirri a kan katunan, kowanne yana amfani da iliminsa na kansa, ba tare da ganin lambar kowa ba. 'Yan kasuwar tulip suna kallon juna suna yin farashi. Lokacin da hukuncin ya zama jere da a fili, taron yana daina zama tarin auna mai zaman kansa kuma yana zama jerin tunani game da tunani — kuma jerin kamar wannan na iya ɗaukar kuskuren girman al'umma akan kusan babu bayanai kwata-kwata. Wannan labarin yana magana ne akan yadda hakan ke faruwa: lissafin cascades, tunanin rukuni, tarin tarihi, da tsarin da ke kiyaye kungiyoyi a gefen da ya dace na juyawa.

Injin cascade

A cikin 1992, Sushil Bikhchandani, David Hirshleifer, da Ivo Welch sun buga "Ka'idar Fad, Fashion, Al'ada, da Canjin Al'adu a matsayin Bayanan Cascades" a cikin Jaridar Tattalin Arziki — ɗaya daga cikin mafi tasiri samfuran a cikin kimiyyar zamantakewa ta zamani. Abhijit Banerjee ya buga "Wani Samfurin Sauƙin Halin Kabilu" a cikin Jaridar Tattalin Arziki ta Kwanaki a cikin wannan shekarar. Tsarin yana da tsauri: mutane suna zaɓar tsakanin zaɓuɓɓuka biyu, ɗaya a lokaci, a fili. Kowanne mutum yana riƙe da sigina na sirri — wani haske mai hayaniya game da wanne zaɓi ne mafi kyau — kuma yana iya ganin zaɓin kowane mutum na baya, amma ba siginar da ke bayan sa ba.

Kalli yadda lissafin ke bayyana. Mutum na farko yana bin siginansa na kansa — shine kawai abin da yake da shi. Mutum na biyu yana ganin zaɓin farko da siginansa na kansa; idan sun yarda, sauƙi, kuma idan sun sabawa, siginarsa aƙalla yana kiyaye shi a cikin jujjuyawar kudi. Amma mutum na uku wanda ke ganin zaɓuɓɓuka biyu masu kama a gaban sa yana fuskantar lissafi: shaidar sigina biyu (da aka fahimta daga zaɓuɓɓukan) a kan guda ɗaya. Ko da idan siginansa na sirri yana ihu akasin haka, motsin Bayesian mai ma'ana shine bi taron. Kuma ga guba: saboda ta yi watsi da siginarta, zaɓinta ba ya bayyana komai. Mutum na hudu yana ganin zaɓuɓɓuka uku masu kama, amma kawai biyu daga cikinsu sun taɓa ƙunshe da bayani. Cascade yanzu yana rufewa — kowane mutum na gaba yana kwaikwayo, babu wani bayanin sirri da ya shiga cikin taron jama'a, kuma juyin daidaito yana ƙaruwa ba tare da wani sabon gaskiya a bayansa ba.

Hanyoyi uku suna fitowa daga samfurin, kowanne an tabbatar da shi a cikin gwaje-gwajen dakin gwaje-gwaje na Lisa Anderson da Charles Holt (American Economic Review, 1997), inda yawancin launin urn ya sake haifar da cascades — ciki har da waɗanda ba daidai ba — tare da mutane na gaske da fa'idodin gaske:

• Cascades suna da ma'ana. Babu mutum guda da ke aikatawa da wayo. Kowanne kwaikwayo yana zama hujja mai inganci daga bayanan da ake da su. Gazawar tana zama ta haɗin gwiwa: bayanan kungiyar suna cikin kwakwalwa da ba su yi aiki a kai ba.
• Cascades suna yawan zama ba daidai ba. Idan sigina na farko biyu sun faru da kuskure — mai yiwuwa daidai tare da bayanan hayaniya — duk taron da ya biyo baya yana kulle kan zaɓin ba daidai ba. Yawan taron, yawan kuskuren yana bayyana.
• Cascades suna da rauni. Saboda daidaito yana dogara ne akan sigina biyu ko uku, ba dubban ba, ƙaramin shigar bayanai na jama'a — mai jituwa ɗaya, gaskiya mai jituwa ɗaya — na iya karya cascade cikin dare. Wannan shine dalilin da ya sa fad ke rushewa cikin sauri kamar yadda suke faruwa, da dalilin da ya sa marubutan samfurin suka sanya sunan sa bayan fashion.

Wannan rauni shine alamar. Gaskiyar jituwa, wanda aka gina daga yawan hukuncin da ba su da alaƙa, yana da ƙarfi ga mai jituwa guda. Jituwa ta cascade gida ce ta katako da ke sanye da kayan gini na ƙaura. Cikakken samfurin, tunaninsa, da aikace-aikacen sa suna samun zurfin kulawa a shafinmu na bayanan cascades.

Ziyara ta tarin ɓarna

Tulip mania, 1636–37 — da cascade game da cascade

Labarin bubble na gargajiya: a lokacin da kasuwar tulip ta Dutch ta kai kololuwa a lokacin hunturu na 1636–37, kwangiloli don rare bulbs sun canza hannaye a farashi da suka yi gasa da gidaje, kafin kasuwar ta rushe a cikin Fabrairu 1637 kuma — labari ya ce — ta lalata wata ƙasa. Karatun zamani yana bayar da labari mai ban sha'awa. Masanin tarihi Anne Goldgar, wanda ke aiki a cikin tarihin Dutch don littafinta na 2007 Tulipmania, ta gano cewa kasuwancin yana iyakance ga wani ƙaramin hanyar sadarwa na 'yan kasuwa da masu sana'a, cewa an rubuta bankin da aka yi kadan, da cewa babbar tattalin arzikin Dutch ta ci gaba ba tare da lalacewa ba. Farashin rare bulbs sun yi tsanani da gaske; lalacewar ƙasa ta zama labari.

Me yasa labarin ya ci gaba? Saboda labarai suna cascade ma. Goldgar ta bi yadda sigar mai ban sha'awa ta sauka daga takardun ladabi da daga littafin Charles Mackay na 1841 Extraordinary Popular Delusions and the Madness of Crowds, wanda aka maimaita daga marubuci zuwa marubuci na tsawon ƙarni — kowanne marubuci yana dogara ga waɗanda suka gabata maimakon duba tarihin. Labarin gargadi mafi shahara game da taron yana da kansa cascade na bayanai: karɓar jere na ikirari bisa ga ganin waɗanda suka karɓa a baya, tare da kusan babu wanda ya tuntubi hujjar farko.

Bubbles na Kudu, 1720

Farashin hannun jarin Kamfanin Kudu ya tashi daga kusan £128 a watan Janairu 1720 zuwa kusan £1,000 a lokacin bazara, wanda aka tura ta hanyar shirye-shiryen canza bashi, tallace-tallace masu ƙarfi, da — mai mahimmanci — kyan gani na makwabta suna samun arziki, kafin ya rushe zuwa ƙasa kafin ƙarshen shekara. Binciken da majalisar ta yi daga baya ya gano cin hanci da rashawa da suka kai ga gwamnati. A matsayin yanayi na bayanai yana da cikakken cascade: sayayya suna da sauƙin ganewa, ainihin makomar kamfanin ba ta da masaniya, kuma kowanne sabon mai saye yana dogara ne akan tunanin cewa yawancin masu saye na baya ba za su iya zama ba daidai ba. Zasu iya, saboda yawancin su suna yin tunani iri ɗaya.

Bay of Pigs, 1961: lokacin da cascade ke faruwa a kan tebur

Bubbles na kasuwa suna haɗa da baƙi; irin wannan yanayin yana aiki tsakanin abokan aiki da ke jin daɗin juna — kuma a can tunanin yana samun ƙarin juyawa. A watan Afrilu 1961, gwamnatin Kennedy ta kaddamar da harin da aka goyi bayan CIA a Cuba ta hanyar kusan 'yan gudun hijira 1,400 a Bay of Pigs. Ya rushe cikin kwanaki uku. Rukunin shawara da ya amince da shi, ta kowanne ma'auni, yana da basira. Masanin tunani Irving Janis ya yi hujja cewa wannan shine babban jigon littafinsa na 1972 Victims of Groupthink, yana tambayar yadda irin wannan rukunin ya amince da shirin da kuskuren sa ya bayyana a gaba — wasu masu ba da shawara, Arthur Schlesinger a cikin su, daga baya sun amince da shakkun da ba su taɓa matsawa a cikin dakin ba.

Amsar Janis ita ce tunanin rukuni: lokacin da haɗin kai da sha'awar jituwa suka wuce kimantawa mai ma'ana, rukunin yana jin ƙarin jituwa fiye da yadda ainihin yake. Ya lissafa alamomi takwas a cikin rukuni uku:

Lura da bambanci daga cascade na kasuwa: 'yan kasuwar tulip sun yi imani da gaske cewa farashi za su tashi. Wanda ya zama mai tunani na rukuni har yanzu yana sabani a cikin sirri — kuma yana ɓoye shi. Abilene Paradox na Jerry Harvey (1974) ya tura wannan zuwa ga karshe mai ban dariya tare da labarin iyali da ke tuki awanni hudu masu zafi, datti zuwa Abilene don cin abinci wanda, bayan haka, ba wanda daga cikinsu ya so: kungiyoyi na iya haɗuwa kan sakamako wanda babu wani memba na mutum ya fi so, saboda kowa yana kuskure shiru na kowa da kowa a matsayin sha'awa. Inda cascade ke lalata bayanai ta hanyar kwaikwayo mai ma'ana, tunanin rukuni yana lalata ta hanyar toshe kai — wani jigo da muke bincika a cikin saitunan rukuni a cikin jagorarmu na yanke shawara na rukuni.

Labarin Bay of Pigs yana da wani aiki na biyu wanda ke tabbatar da cewa gazawar ta kasance ta tsarin, ba ta mutum ba. Watanni goma sha takwas daga baya, yayin da suke fuskantar rikicin makaman nukiliya na Cuba, Kennedy ya tsara yadda wannan rukunin na masu ba da shawara ya tattauna — Janis kansa ya jera bambancin. An ba Robert Kennedy aikin yin mai jituwa, rukunin ya rabu zuwa ƙananan rukuni da suka haɓaka zaɓuɓɓuka a cikin 'yancin kai kafin su kwatanta su, an kawo ƙwararru daga waje, kuma shugaban ya bar zaman don kada sha'awarsa ta zama tushe ga dakin. Mutane iri ɗaya, tsarin daban, da tattaunawa da ta bayyana da kuma gwada zaɓuɓɓuka maimakon amincewa da shirin farko a kan tebur.

Dot-com da bubble na gidaje: cascades tare da plumbing na zamani

NASDAQ Composite ya kai kololuwa a 5,048.62 a ranar 10 ga Maris, 2000, kuma ya rasa kusan 78% na darajar sa a lokacin raguwa a cikin Oktoba 2002. Manhajar bubble tana da sananne — kowanne zagaye na kuɗi, IPO pop, da murfin mujallar shine alamar jama'a cewa mutane masu hankali da yawa ba za su iya zama ba daidai ba — wanda aka ƙara ta hanyar sabuwar fasaha wacce ke da wahalar kimanta, wanda shine lokacin da sigina na sirri ke rauni kuma kwaikwayo yana zama mai jawo hankali. Rikicin gidaje na 2008 ya ƙara wani mai saurin gini: yawan imani cewa farashin gidajen Amurka ba sa faɗuwa a ƙasa baki ɗaya shine kuskuren haɗin kai — wanda aka raba tsakanin masu aro, masu ba da lamuni, hukumomin kimantawa, da masu kula — kuma securitization ta yada wannan tunani guda ɗaya ta hanyar duk tsarin kuɗi. Lokacin da kuskure suka haɗu, tarin ba ya juyawa; yana mai da su. Wani jari mai bambanci na caca wanda dukkan su suna dogara da wannan imani guda ɗaya ba ya bambanta kwata-kwata.

Cascades a saurin intanet

Kafofin watsa labarai na zamantakewa na'ura ce ta cascade ta hanyar gini: rabawa yana jere, a fili, da sauƙi, kuma tabbatar da ikirari yana da tsada — daidai tsarin da samfurin 1992 ya bayyana a matsayin mai yiwuwa na cascade. Babban binciken kimiyya shine Soroush Vosoughi, Deb Roy, da Sinan Aral's "Yaduwar gaskiya da labaran karya a kan layi" (Kimiyya, 2018), wanda ya nazarci kusan 126,000 na labaran da aka tabbatar da cascades a kan Twitter a cikin shekaru goma sha ɗaya. Labaran karya sun yadu sosai, da sauri, da zurfi fiye da gaskiya, kuma labaran karya sun kasance kusan 70% fiye da yiwuwar a sake raba su — wani tasiri da mutane ke haifarwa, ba bots ba, a bayyane saboda labaran karya sun fi sabo da kuma jawo hankali.

Wani sabon damuwa yana kan gabar. Wani hangen nesa na marubuci 28 wanda Jason Burton ya jagoranta (Nature Human Behaviour, 2024) ya duba yadda manyan samfuran harshe na iya sake fasalin basirar tarayya — kuma ya nuna homogenization a matsayin babban haɗari: lokacin da miliyoyin mutane suka tuntubi waɗannan ƙananan samfuran, wanda aka horar a kan bayanai masu jituwa, hukuncin su na 'yancin kai yana haɗuwa a hankali. Al'umma da ta ba da tunaninta ga wani mai haske a cikin sharuɗɗan cascade, taron mutum guda ne. Amsoshin mutum na iya zama masu kyau; bambancin da ke sa tarin ya yi aiki shine abin da ke rushewa — damuwa da ke haɗe kai tsaye da son kai na atomatik da daidaiton amincewa a cikin tsarin mutum-AI.

Jagorar filin: cascade, tunanin rukuni, ko kabilu?

“Kabilu” shine kalmar rufewa don halayen da suka haɗu; hanyoyin da ke ƙasa suna bambanta, haka nan gyaran. Wani gajeren tsarin:

Gaskiyar bala'o'i yawanci suna haɗa duk uku. Masanin gidaje a cikin 2006 ya fuskanci cascade (duk samfuran suna cewa farashi suna tashi), tunanin rukuni (al'adar dakin tana hukunta rashin fata), da kabilu na fa'ida (aikin yana lafiya a cikin jituwa). Wannan shine dalilin da ya sa magungunan da ke ƙasa suna kai hari ga tsarin maimakon ƙarfafa mutane su zama masu ƙarfin gwiwa.

Yadda za a karya cascade

Kowane ingantaccen mataki na kariya yana yin ɗaya daga cikin abubuwa biyu: yana dawo da 'yancin kai ga hukuncin mutum, ko yana mika bayanan sirri cikin taron jama'a. Kayan gargajiya:

Tsarin a matsayin magani: raba gudummawa daga lura

Duba baya ga tsarin ruwan sama da gazawar tana da takamaiman wuri: lokacin da mutum ya ga zaɓin wasu kafin ya yanke hukuncin kansa. Wannan shine haɗin inda tsarin zai iya shiga. Argumentree an gina shi a kan wannan shiga don yanke shawara tare: mahalarta suna bayar da hujjoji a cikin 'yanci da ba tare da jinkiri ba - suna rubuta dalilansu kafin dakin ya haɗu - tare da bayar da gudummawa ba tare da suna ba inda matsin lamba na matsayin shine haɗarin. Hujjoji suna haɗuwa da ƙungiyar a matsayin rassan pro da con da aka kimanta bisa ga fa'idodinsu (amfani, bayyana, daidaito, cikakkun bayanai), don haka goyon bayan matsayin yana nuna shaidarsa maimakon tsarinsa.

Kuma saboda cikakken hanyar bincike tana adana dalilin kowanne matsayin da aka ɗauka, ƙungiyar ba ta fuskanci jahilcin asali na ruwan sama - zaɓuɓɓuka suna bayyane, dalilai ba su bayyana ba. Rikodin yanke shawara tare da dalilin da aka haɗa shine daidaitaccen ma'auni na wallafa sigina na sirri: mahalarta daga baya, da yanke shawara daga baya, suna gaji bayanan maimakon kawai daidaituwa. Tattalin arziki yana zama kayan auna maimakon zama dakin echo.