مقایسهٔ روش‌ها

	آزمون علامت (Sign Test)	آزمون فریدمن
حوزه	آمار	آمار
خانواده	Hypothesis test	Hypothesis test
سال پیدایش	1946	1937
پدیدآور	W. J. Dixon & A. M. Mood	Milton Friedman
نوع	Nonparametric median test	Nonparametric repeated-measures comparison (by ranks)
منبع بنیادین	Dixon, W. J. & Mood, A. M. (1946). The statistical sign test. Journal of the American Statistical Association, 41(236), 557–566.	Friedman, M. (1937). The use of ranks to avoid the assumption of normality implicit in the analysis of variance. Journal of the American Statistical Association, 32(200), 675–701.
نام‌های دیگر	İşaret Testi (Sign Test), one-sample sign test, paired sign test	Friedman two-way analysis of variance by ranks, Friedman rank test, Friedman Testi
مرتبط	4	2
خلاصه	The sign test is the simplest nonparametric hypothesis test for deciding whether the median of paired differences — or of a single sample — differs significantly from a hypothesised value. Formalised by W. J. Dixon and A. M. Mood in 1946, it imposes virtually no distributional assumptions and can be applied to any data where individual differences can be classified as positive or negative.	The Friedman test is a nonparametric hypothesis test that compares three or more related conditions measured on the same blocks or subjects, serving as the rank-based alternative to repeated-measures ANOVA. It was introduced by Milton Friedman in 1937 and works on ordinal or continuous data without assuming normality.