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--- en:general:indices [02.04.2015 17:32] – oezbf2012
+++ en:general:indices [02.04.2015 17:34] – [Frequently Asked Questions] oezbf2012
@@ Line 78: / Line 78: @@
 Yes and no. In principle the size of the correlation is independent from the number of items. However, in a neatly constructed scale the quality of the measurement is increased by the number of items. Therefore the scale index contains fewer measurement errors and as a result higher correlations may be observed.
-To the contrary a correlation based on more items can actually be overrated if both constructs underlie the same measurement error. The higher correlation with more items is a spurious correlation in this case – e.g. because some people prefer to answer on the right end of the scale (acquiescence).
+On the contrary a correlation based on more items can actually be overrated if both constructs underlie the same measurement error. The higher correlation with more items is a spurious correlation in this case – e.g. because some people prefer to answer on the right end of the scale (acquiescence).
 **What is the measurement level of scale indices?**
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 **Are scales with reversed-polarity items preferable?**
-This question cannot be answered in general.
+There is no general answer to this question.
 The use of reversed-polarity items will usually result in the effect that the correlation between items (Cronbach's alpha) is slightly lower. Basically that is not desirable – but might as well be an indicator that the respondents have made their answer thoughtfully. In addition, a general tendency to approval/rejection is extenuated by the use of reversed-polarity items. This results in a superior measurement of the construct.