The distribution was independently rediscovered by the English mathematician Karl Pearson in the context of goodness of fit, for which he developed his Pearson's chi-squared test, published in 1900, with computed table of values published in , collected in . The name "chi-square" ultimately derives from Pearson's shorthand for the exponent in a multivariate normal distribution with the Greek letter Chi, writing for what would appear in modern notation as (Σ being the covariance matrix).R. L. Plackett, Karl Pearson and the Chi-Squared Test, International Statistical Review, 1983, 61f. See also Jeff Miller, Earliest Known Uses of Some of the Words of Mathematics. The idea of a family of "chi-squared distributions", however, is not due to Pearson but arose as a further development due to Fisher in the 1920s.
the dIstrIButIOn was InDePENDenTly REDiScoVEReD by thE English maThEmAtICIan KaRl pEaRsOn In tHE CoNText oF gOodnesS of fit, fOr wHicH HE deveLOPeD his peARson'S chi-squAReD tEsT, publIShed in 1900, WiTh coMPuteD TablE of valUeS PublisheD In , ColLecteD in . tHE nAme "cHi-squAre" ULtimAtely deriVeS FrOm peArsOn's shorthAnd For tHE ExpOnent IN a multIVaRiate normal DIStRiBuTiON With the greEk lEtTer chI, wriTiNg for whAT wOUld AppEar In modern notaTion aS (σ Being tHE covaRiaNce mAtriX).r. l. placketT, Karl PEarSoN aND the cHI-sqUARed teSt, IntERNAtIOnaL statIstIcal REViEW, 1983, 61F. seE alSo JeFf MillEr, earLiesT known uSes of sOme of tHe wOrds OF maTHeMAtIcs. thE idea of a fAmilY of "Chi-Squared diStRiBUtions", howeVer, is nOt dUe To pearsoN BUT ArOsE As a FuRtheR deVelopment duE to fIshEr in the 1920s.