Why would a researcher remove items which load onto more than one component after rotation in PCA using Varimax?
A couple of studies I'm using as the basis for a study I'm conducting have done this but did not explain why.
The only explanation I can think of is that because the factors are supposed to be unrelated with varimax - the presence of items which load heavily onto 2 factors questions the results.
I'm more familiar with regular Factor Analysis, where it doesn't seem to be an issue if an item loads onto 2 or more factors. I can't seem to find any literature on this specific, so any help would be appreciated.
My problem is I am currently doing my Final Year Project for my undergraduate degree which aims to determine if there are underlying organistional cultural factors to the restaurant industry in Dublin. I'm using a shortened version of a scale called the Organistional culture profile, which uses 40 items to measure culture. originally the authors used PCA and varimax to discern the factors/componants, in a sample of american accountants. i aim to use the same method to have a look at the factors underlying dublin restaurant workers culture - which i predict will be somewhat different as it is in a different industry and country. wanting to follow the original authors method as closely as possible i have also used PCA and varimax. the authors removed any items which did not load on any factors (fair enough), but also factors which loaded highly (>.4) on more than one factor. Following their lead, and also (i thought) getting their logic (i assumed they expected the factors to be unrelated as the used Varimax, an orthoganal rotation) I too removed all highly cross-loading items and ran the PCA again. my problem is now that 5 different items/variables are crossloading on factors in the new rotated factor matrix. I can't get my head around how this could happen - surely if they didn't cross load in the first PCA they shouldn't in the second? additionally - if i was to follow the same logic and remove these variables as they cross load....... sorry for the long winded rant , but i am stumped!