Harry Markowitz

**Harry Max Markowitz** (24 ga Agusta, 1927 - 22 ga Yuni, 2023) masanin tattalin arziki ne na Amurka wanda ya sami lambar yabo ta John von Neumann Theory Prize ta 1989 da lambar yabo ta Nobel Memorial a fannin kimiyyar tattalin arziki ta 1990.

Markowitz ya kasance farfesa a fannin kudi a Makarantar Gudanarwa ta Rady a Jami'ar California, San Diego (UCSD). An fi saninsa da aikinsa na farko a cikin Ka'idar fayil na zamani, yana nazarin tasirin haɗari dukiya, dawowa, daidaituwa da rarrabuwa a kan yiwuwar dawowar saka hannun jari.

## Tarihin rayuwa
An haifi Harry Markowitz ne a cikin iyalin Yahudawa, ɗan Morris da Mildred Markowitz .  A lokacin makarantar sakandare, Markowitz ya ci gaba da sha'awar kimiyyar lissafi da falsafar, musamman ra'ayoyin David Hume, sha'awar da ya ci gaba a lokacin da yake karatun digiri a Jami'ar Chicago. Bayan ya sami Ph.B. a cikin Liberal Arts, Markowitz ya yanke shawarar ci gaba da karatunsa a Jami'ar Chicago, ya zaɓi ya ƙware a fannin tattalin arziki. A can ya sami damar yin karatu a ƙarƙashin manyan masana tattalin arziki, ciki har da Milton Friedman, Talling Koopmans, Jacob Marschak da Leonard Savage . Yayinda yake dalibi, an gayyace shi ya zama memba na Hukumar Cowles don Bincike a Tattalin Arziki, wanda ke cikin Chicago a lokacin. Ya kammala karatunsa na A.M. a fannin tattalin arziki daga jami'a a shekarar 1950. 

Markowitz ya zaɓi yin amfani da lissafi ga nazarin kasuwar jari a matsayin batun rubutun sa. Jacob Marschak, wanda shine mai ba da shawara, ya ƙarfafa shi ya bi batun, yana mai lura da cewa shi ma abin sha'awa ne na Alfred Cowles, wanda ya kafa Hukumar Cowles. Yayinda yake bincike kan fahimtar farashin hannun jari na yanzu, wanda a lokacin ya kunshi tsarin darajar yanzu na John Burr Williams, Markowitz ya fahimci cewa ka'idar ba ta da bincike game da tasirin haɗari. Wannan fahimtar ta haifar da ci gaban ka'idarsa ta asali game da rabon fayil a ƙarƙashin rashin tabbas, wanda aka buga a 1952 ta *Jaridar Kudi*.

A shekara ta 1952, Harry Markowitz ya tafi aiki ga Kamfanin RAND, inda ya sadu da George Dantzig . Tare da taimakon Dantzig, Markowitz ya ci gaba da bincike kan dabarun ingantawa, ci gaba da bunkasa mahimman layin algorithm don gano mafi kyawun ma'auni-canji, yana dogaro da abin da daga baya aka kira iyakar Markowitz. Har ila yau, a cikin 1952 ne Markowitz ya buga Portfolio Selection, takarda ta farko da ke rarraba dabarun saka hannun jari.

A shekara ta 1954, ya sami digirin digirin digirgir a fannin tattalin arziki daga Jami'ar Chicago  tare da rubutun kan ka'idar fayil. Batun ya kasance sabon abu ne, yayin da Markowitz ke kare rubutun sa, Milton Friedman ya yi jayayya cewa gudummawarsa ba tattalin arziki ba ne. A cikin 1955-1956 Markowitz ya shafe shekara guda a Gidauniyar Cowles,  wacce ta koma Jami'ar Yale, a gayyatar James Tobin. Ya buga mahimmin layin algorithm a cikin takarda ta 1956 kuma ya yi amfani da wannan lokacin a tushe don rubuta littafi game da rabon fayil wanda aka buga a 1959. 

### CACI
Kamfanin da zai zama CACI International ne Herb Karr da Harry Markowitz suka kafa shi a ranar 17 ga Yuli, 1962, a matsayin Cibiyar Nazarin California, Inc. Sun taimaka wajen bunkasa SIMSCRIPT, harshen shirye-shiryen kwaikwayo na farko, a RAND kuma bayan an sake shi zuwa yankin jama'a, an kafa CACI don samar da tallafi da horo ga SIMSCRipT. 

A shekara ta 1968, Markowitz ya shiga kamfanin Arbitrage Management wanda Michael Goodkin ya kafa. Yin aiki tare da Paul Samuelson da Robert Merton ya kirkiro asusun ajiya wanda ke wakiltar daya daga cikin yunkurin farko da aka sani na cinikin arbitrage na kwamfuta. Ya zama shugaban zartarwa a shekarar 1970. Bayan nasarar da aka samu a matsayin asusun ajiya mai zaman kansa, an sayar da AMC ga Stuart & Co. a shekarar 1971. Bayan shekara guda, Markowitz ya bar kamfanin.

Shekaru bayan haka, ya shiga cikin CACI's SIMSCRIPT kari na Abubuwan da suka dace.

### Bayan CACI
Markowitz ya raba lokacinsa tsakanin koyarwa (ya kasance mataimakin farfesa a Makarantar Gudanarwa ta Rady a Jami'ar California a San Diego, UCSD); laccocin jefa bidiyo; da kuma ba da shawara (daga ofisoshin Kamfanin Harry Markowitz). Ya yi aiki a kwamitin ba da shawara na SkyView Investment Advisors, kamfanin ba da shawara kan saka hannun jari na gargajiya da na madadin. Markowitz ya kuma yi aiki a Kwamitin Zuba Jari na LWI Financial Inc. ("Loring Ward"), mai ba da shawara kan saka hannun jari na San Jose, California; a kan kwamitin ba da shawara na kamfanin kula da saka hannun jari ya Robert D. Arnott, California, Research Affiliates; a kan hukumar ba da shawara ta Mark T. Hebner's Irvine, California da kuma kamfanin kula da dukiya da haraji na intanet, Index Fund Advisors; kuma a matsayin mai ba da shawarar kwamitin saka hannun jari ta 1st Global, kamfanin gudanar da saka hannun jarin Dallas, Texas. Markowitz ya ba da shawara kuma ya yi aiki a kan kwamitin ProbabilityManagement.org, wani 501 (c) (3) ba da riba ba wanda ke da niyyar "sake fasalin sadarwa da lissafin rashin tabbas".

Markowitz ya kasance co-kafa kuma Babban Architect na GuidedChoice, mai ba da asusun ajiya na 401 (k) da mai ba da shawara kan saka hannun jari. Ayyukan Markowitz na baya-bayan nan sun haɗa da tsara nazarin software na kashin baya don maganin saka hannun jari na GuidedChoice da kuma jagorantar Kwamitin saka hannun jari. Ya kasance yana da hannu sosai wajen tsara mataki na gaba a cikin tsarin ritaya: taimakawa masu ritaya tare da rarraba dukiya ta hanyar GuidedSpending.

## Bincike da Gudummawar Tattalin Arziki

### Binciken Bambanci
Babban gudummawar Markowitz shine ƙaddamar da cinikayya ta haɗari. Ya nuna ta hanyar lissafi cewa mai saka hannun jari na iya rage daidaitattun karkatarwa na fayil ta hanyar zabar kadarorin da ba su da cikakkiyar alaƙa.