Hi there,

I am hoping that someone might be able to help me with data analysis/structuring.

My data is exploring whether two psychometrics (treated as separate variables, not combined) can effect task performance (reaction time and error rate) when exposed to certain stimuli in a given task. In this task, I have 48 trials where trials 1-12 show one image, trials 13-25 show a second image, and trials 26-48 show a third image. As a brief example, my data looks something like this:

Unfortunately, I cannot restructure the data from wide to long because the lengths of the variables I want to restructure are not the same (I have around 8 other variables I would ideally like to explore on top of this). This would also duplicate the psychometric scores (each participant would have 12 inputs instead of just 1 for the mean score) which I think would effect any analysis. I tried manual entry as far as I could but, with over 150 participants, this would take several hours of entry that is open to human error. 

Is there any way that I can tell SPSS to categorise specific trials that are spread across multiple variables? I have tried re-coding, transposing, manual entry and aggregating but I think I am just not able to figure this one out myself. I am not used to running Syntax, but am open to learning.

If this is not possible, then I would be extremely grateful to hear what analysis ideas anyone might have as an alternative approach. Any help that anyone could provide would be greatly appreciated. Thank you.

Hi Jon, 

Thank you for the prompt suggestion. I have had a look at autorecoding and run some tests, but it seems that I cannot state that variables 1-12 fall under one group and they just get treated as 12 new variables (which I think is almost like the standard recoding process). Perhaps I am going about this wrong. Do you happen to know of step-by-step tutorials you would recommend for marking several variables as one category for analysis?

Just to add in an edit as I think this was not clear, sorry - I am trying to retain the reaction time data within each cell. So participant 1 had a reaction time across all trials, but only parts of those trials were in response to certain images. This is where the restructuring fails, because I cannot retain the psychometric data for each participant as this will only have 12 cells of data compared to the 48 cells of data for the reaction time task.

Thank you again for the help so far.

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Ash
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