Screening Phase

Examine data for five different kinds of possible errors:

1. Lack of data – Do some questions have far fewer answers than surrounding questions?
2. Excess of data – Are there duplicate responses?
3. Outliers/inconsistencies – Are there values that are so far beyond the typical that they seem potentially erroneous?
4. Strange patterns – Are there patterns that imply cheating rather than honest answers?  For instance, does a respondent alternate between ratings of 4 and 5 on every other topic in a matrix question?
5. Suspect analysis results – Do the answers to some questions seem counterintuitive or extremely unlikely?