השוואת שיטות

	מערך סולומון לארבע קבוצות	ניסוי פקטוריאלי
תחום	תכנון ניסויים	תכנון ניסויים
משפחה	Process / pipeline	Process / pipeline
שנת המקור	1949	1926–1935
הוגה השיטה	Richard L. Solomon	Ronald A. Fisher
סוג	True experimental design	Quantitative experimental design
מקור מכונן	Solomon, R. L. (1949). An extension of control group design. Psychological Bulletin, 46(2), 137–150.	Fisher, R. A. (1935). The Design of Experiments. Oliver and Boyd.
כינויים	Solomon design, four-group design, Solomon four-group control design, S4GD	factorial design, factorial ANOVA design, multi-factor experiment, crossed-factor design
קשורות	5	6
תקציר	The Solomon Four-Group Design extends the classic pretest-posttest control-group design by adding two groups that receive no pretest, enabling researchers to detect whether the pretest itself alters participants' responses to the treatment. Introduced by Richard L. Solomon in 1949, it remains the gold standard for isolating the independent effect of a pretest and for obtaining unbiased estimates of treatment efficacy.	A factorial experiment is an experimental design in which two or more independent variables (factors) are manipulated simultaneously, and every combination of their levels is tested. Introduced by Ronald Fisher in the 1920s–1930s, it is the standard approach whenever a researcher needs to detect not only the main effect of each factor but also whether the effect of one factor depends on the level of another — the interaction effect.