Can the function 'anovan' handle unbalanced designs?
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Hello Guys,
imagine the following experimental setup for an unbalanced, mixed-ANOVA:
Unbalanced, non-repeated ANOVA with REPLICATION using 
continous & categorical predictors 
Entity tested: Washing powder
Outcome variable [continous]: Amount of living mites after one washing cycle (integer)
1st Predictor [continuous]:     Amount of washing powder in gram [0:20:80]
2nd Predictor [categorical]:    Branch of washing powder [Lenor, Spee]
3rd Predictor [categorical]:    Branch of washing machine [Bosch, Siemens]
Number of possible predictor combinations: 5 levels * 2 Levels * 2 levels = 20
REPLICATION part of design: experiment is replicated 50 times for
each predictor combination.
     -> e.g.
     50 cycles, 0 gram, Lenor, Bosch
     50 cycles, 0 gram, Lenor, Siemens
     50 cycles, 0 gram, Spee,  Bosch
     50 cycles, 0 gram, Spee,  Simens
     same for 20, 40, 60, 80 gram
UNBALANCED part of design:
     1 cycle missing for 20g, Lenor, Bosch 
     1 cycle missing for 60g, Lenor, Bosch
     -> 18 predictor combinations have 50 cycles, 2 have only 49 cycles
     -> Total washing cycles: 50cycles*5*2*2 - 2 = 998
Non-repeated part of design:
     Different entities are used to test all predictor-level combinations 
     (the same washing powder unit is not/can not be used in two different washing cycles)
Is the function 'anovan' able to handle a situation like that, in which not all predictor-combinations have the same number of repetitions?
I would use the following input arguments and Name-Value-Pairs to run the mixed-ANOVA. Would this be adequate given the upper example?
[mixedANO.p, mixedANO.tbl, mixedANO.stats, mixedANO.terms] = anovan(y, groups, ...
                                                            'model', 'full', ...
                                                            'continuous', [1], ...
                                                            'varnames', {'WP used', 'WPbranch', 'WMbranch'});
Thanks a lot!
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