======= Date Modified 02 18 2010 09:18:25 =======
Sorry for another design related question, but its hopefully a relatively straight forward one... :$
I'm reading a paper which has 140 babies as the sample. There are two test conditions - one were face stimuli is presented to the baby and one were they are presented with a mechanical object. The researchers are just interested in differences between which stimuli the female babies prefer and which the males prefer. All straight forward enough. However there are 90 girls and 50 boys, does this mean its an unbalanced design?
I know an unbalanced design is one where there are unequal participants in each treatment group but I can't decide whether this applies to this experiment or not.
I've got two ideas:
1.) Its repeated measures, so if the treatment groups are just 'face' and 'object' then there is the same amount of participants in each treatment group as each participant takes part in both conditions. So it is a balanced design??
or
2). The treatment groups would actually be defined as 'Girls-Face, Girls-Object, Boys-Face, Boys-Object' in which case there is not the same amount of participants in each group, so it is an unbalanced design??
Argh, does that make any sense? If someone could shed some light it would be much appreciated :-)