Re: What is the best approach for my research?

Posted by Ryan on Feb 23, 2012; 1:36pm
URL: http://spssx-discussion.165.s1.nabble.com/What-is-the-best-approach-for-my-research-tp5507150p5508065.html

Well, instead of dealing with 18 DVs, you would have a single "measure" of comprehension on which you can compare differences between conditions. 

There are certain details to this study that make it particularly challenging, not the least of which is the clustering of subjects in juries. This clustering (a.k.a. nesting) should be considered in order to arrive at the optimal data analytic strategy for your study. No more time to discuss at the moment. Hope this gives you some direction. Perhaps others can provide additional feedback.

Ryan

On Thu, Feb 23, 2012 at 8:13 AM, Benjamin Spivak <[hidden email]> wrote:

Hi Ryan,

Thank you very much, I will look at Rasch models and attempt to apply it to my work. Could I trouble you with another question. 

Say, I do find that there is a uni-dimensional construct underlying comprehension. How could this assist me to look for differences between conditions?

Regards,

Ben

On 23 February 2012 23:41, R B <[hidden email]> wrote:

Benjamin,

The first thing I would consider would be whether there is an underlying unidimensional construct underlying comprehension. You could fit a Rasch model via Winsteps, which allows for items with varying response options.

Ryan

On Thu, Feb 23, 2012 at 1:14 AM, Benjamin Spivak <[hidden email]> wrote:

Dear List,

 

Please help I am stuck. I am performing some jury research with some very strange result and I want to find the ideal statistical model to fit my data.

 

My study. Essentially a 2x3 jury simulation study measuring comprehension of law. I also have over 18 DV's (questions) for comprehension. I have considered condensing the questions into one variable. But Cronbach's alpha is quite low for any combination of questions that I can relate to one construct.

 

Distribution is extremely non-normal and there is a heterogeneity of variance between groups. Also, because the jury study uses deliberating groups I have violated the assumption of independence.

 

Considering all this, I am having real trouble determining what the best approach for analysis would be. I have tried multi-level linear modelling, but I get results that I cannot make sense of.

 

I am at my wits end. If somebody could help, I would be in their debt.

 

Regards,

 

Ben.

 

 

 

 I would like to analyze individual jury data, but clearly my model violates the assumption of independence. So I have to account for this.