I received the following question by email and have seen a lot of students with this problem:
I am trying to fit a structural equation model in Amos, but when I click "calculate estimates", I get the following error: "observed variable [variable name] is represented by an ellipse in the path diagram". Could you please advise me of what I am doing wrong?
IBM Help discusses this error but isn't that helpful.
In practice, I've seen this error come up a number of times. It can occur because you have incorrectly specified a variable as latent that you wanted to be observed. However, more commonly, it is the result of giving an inappropriate variable to a latent variable. Specifically, it is relatively easy to give a name to a latent factor that is the same as an observed variable in your data file.
For example, one time I had some personality variables in a dataset and the extraversion items were called E1, E2, E3, and so on. These are common names for residuals. So when giving residuals these names, there was a conflict with the names in the data file.
Another even more common cause is when you name a latent factor an appropriate name (e.g., selfesteem, extraversion, jobsatisfaction, etc.) and you have already created a scale score in your data file with the same name. This also causes the conflict.
The basic solution is just to give the latent variable a unique name that doesn't conflict with one in the data file. So for example, name the variable selfesteem_factor rather than selfesteem if you already have a variable called selfesteem.
I recently experienced the same problem. I followed Jeromy's advise and it worked. Actually that error message is caused by you giving the same name to a latent variable and an observed variable. In my case, I had a latent variable, trust, but I had also created a summated scale for trust(making it become an observed variable). So I got the same error message. when I changed the name of the latent variable, the model run properly
