The effect of apex-finding errors on factor images obtained from factor analysis and oblique transformation

The use of an oblique transformation to obtain physiological factors from a factor analysis of dynamic studies has recently been suggested. The technique involves using an apex-seeking routine to enable these factors and their contribution images to be formed. This paper investigates the effects of errors in apex-finding on these factor images. In particular it is shown that, apart from scaling, the factor image obtained from a given apex is independent of the position of that apex (and hence is independent of its own factor).