Gwajin chi-square
Gwajin ƙididdiga da ke kwatanta yawan faɗuwar ƙwallo da aka gani a kowane rami da abin da ake tsammani, n/37. Ana amfani da shi don tantance ko dabaran ya karkata.
A cikin mahallin amfani
Ku tara (abin da aka gani − abin da ake tsammani)² / abin da ake tsammani a kan ramukakayan aikiRamiƊaya daga cikin ɗakuna 37 masu lamba a kan rotor. Ana kuma kiransa: slot, cup.Karanta gaba ɗaya → 37; ku kwatanta da rabe-raben chi-square a kan degrees of freedomgwajiDegrees of freedomYawan ƙimomi masu zaman kansu a cikin wata ƙididdiga. A gwajin chi-square a kan ramuka 37, 36 ne, saboda dole ne ƙirge-ƙirgen su haɗu su ba da jimillar.Karanta gaba ɗaya → 36.
Karl Pearson ya wallafa gwajin a 1900, kuma ɗaya daga cikin misalansa na farko juye-juyen roulette 26,306 ne da aka rubuta a Monte Carlo, waɗanda ya ga kamar ba na kwatsam ba ne. Binciken da aka yi daga baya ya nuna cewa ʼyan jaridar da suka rubuta su sun ƙirƙiri wasu.