Jenny Goodspeed ([EMAIL PROTECTED]) wrote:
: I have a question regarding the creation of an
: overall scale from several likert-type items.
:
: I have a group of items that I'd like to sum to
: create the scale. Results of a factor analysis show
: that the items load high on one factor. The items
: also have a high alpha coefficient.
:
: However, some of the items have a 4-point scale,
: while the remaining have a 7-point scale. Is this a
: problem?
:
: If so, do I need to use factor score coefficients to
: create the scale? If I'm am doing such, do I need
: to standardize the items first? How do I do this?
:
: I'd appreciate any help anyone can give.
:
:
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Hi Jenny -
ussing scales with different numbers of points might
confuse your subjects. As far as weighting items by factor scores -
evaluate the reliability of your scale using both weighted and weighted
items to see which has better reliability. Typcially - using weights
doesn't improve reliability much but it does make things more
complicated. You should check out Streiner and Norman - Health
measurement scales: a practical guide to their development and use (2nd ed.).
Kent.
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