Meanings
- humorousuncountablethe practice of deciding between statistical models based on a plot, rather than a formal procedure.
They deem a fit acceptable if a graph of data and model "looks good." This approach is known as chi-by-eye. Luckily, its practitioners get what they deserve.
2007, William H. Press, Saul A. Teukolsky, William T. Vetterling, Brian P. Flannery, Numerical Recipes: The Art of Scientific Computing, page 7741 more example
Their business prospects and earnings are correlated, and this can be observed by visually plotting their stock prices. Statisticians often call this "chi by eye."
2011, Steven P. Greiner, Ben Graham Was a Quant : Raising the IQ of the Intelligent Investor, page 16
Origin
Alluding to the χ² test ("chi squared test") used to formally test a statistical hypothesis.
Full word history & related roots →Cite this entry
chi-by-eye. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/chi-by-eye
“chi-by-eye.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/chi-by-eye. Accessed November 2, 2026.
WatkinsX Dictionary, s.v. “chi-by-eye,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/chi-by-eye.
Source: chi-by-eye on Wiktionary, CC BY-SA 4.0.