Help needed for SPSS 2 way ANOVA - Don't understand where to put replicates (Feb/05/2011 )
Hi, any help would be greatly appreciated
I am a undergraduate honors student testing egg production in response to estrogen hormones in a snail species. I have 5 treatment/exposures (continous independent variable) with 6 replicates of 10 individuals per treatment.
I am using SPSS but I am unsure what the best model to use would be. I talked to a clinical statisican the other day and he suggested doing a a 2x2 ANOVA.
I am not entirely sure where to place replicates in the model. I'm using GLM>Univariate and have exposure + replicate + day columns placed in fixed factors is this the right way to go about?
I know I shouldn't be using repeated measures because snails never recieve more than one treatment; 10 new snails were used for each replicate per exposure.
Iím not sure if I understand your design (5 treatments each with 10 snails, repeated 6 times?) but it seems that the only reason for doing a 2 way ANOVA would be to check if the replicates are different.
But it reads as if you are looking for a dose response against exposure in which case regression may give a better analysis.