Pencilan: Perbedaan antara revisi

Dalam ilmu [[statistika]], sebuah '''pencilan''' adalah [[titik data]] yang terpaut jauh dari titik data lainnya.<ref>{{Cite journal |last=Grubbs |first=F. E. |date=February 1969 |title=Procedures for detecting outlying observations in samples |journal=Technometrics |volume=11 |issue=1 |pages=1–21 |doi= 10.1080/00401706.1969.10490657|quote=An outlying observation, or "outlier," is one that appears to deviate markedly from other members of the sample in which it occurs.}}</ref><ref>{{cite book |last=Maddala |first=G. S. |author-link=G. S. Maddala |chapter=Outliers |title=Introduction to Econometrics |location=New York |publisher=MacMillan |edition=2nd |year=1992 |isbn=978-0-02-374545-4 |pages=[https://archive.org/details/introductiontoec00madd/page/89 89] |quote=An outlier is an observation that is far removed from the rest of the observations. |chapter-url=https://books.google.com/books?id=nBS3AAAAIAAJ&pg=PA89 |url=https://archive.org/details/introductiontoec00madd/page/89 }}</ref> Pencilan kemungkinan dapat berasal dari variabilitas pengukuran atau [[galat]] percobaan. Pencilan akibat galat seringkalisering kali diabaikan.<ref>{{harvnb|Grubbs|1969|p=1}} mengatakan "An outlying observation may be merely an extreme manifestation of the random variability inherent in the data. ... On the other hand, an outlying observation may be the result of gross deviation from prescribed experimental procedure or an error in calculating or recording the numerical value."</ref> Pencilan dapat mengakibatkan masalah serius dalam analisis statistik.