(1) Exist a package to do something like missing value analysis for a specific data.frame? (2) Know anybody ,how it is possible check the data for plausibility from one respondend. So i would like identify critical fake respondents and clean them from further analysis.. In Conjoint-Mesaurement data, a plausability test are done with correlation - is something similar possible in a standard survey !? ..until now i didn''t get a good idea which statistic-method could support me for this? many thanks for any suggestions christian [[alternate HTML version deleted]]