When sample sizes and/or X intervals are unequal, the analysis of variance computations for trend analysis become quite complicated. This is because the usual simplicity of analysis of variance algorithms depend upon "regular" conditions for which sources of variance are orthogonal. This article shows how multiple regression/ correlation analysis, a more general procedure that allows for non-orthogonality, may be applied in order to accomplish with great simplicity trend analysis under "irregular" conditions.
Get full access to this article
View all access options for this article.
References
1.
Cohen, J.Partialled products are interactions; partialed powers are curve components. Psychological Bulletin , 1978, 85, 848-866.
2.
Cohen, J. and Cohen, P.Applied multiple regression/correlation analysis for the behavioral sciences . Hillsdale, N. J.: Lawrence Erlbaum Associates, 1975.
3.
Gaito, J.Unequal intervals and unequal n in trend analysis. Psychological Bulletin, 1965, 63, 125 -127.
4.
Gaito, J.Equal and unequal n and unequal intervals in trend analysis. EDUCATIONAL and PSYCHOLOGICAL MEASUREMENT, 1977, 37, 283-289.
5.
Winer, B. J.Statistical principles in experimental design. (2nd ed.) New York: McGraw-Hill, 1971.
